50278 + Interview Questions in Physics

1.	A transistor is connected in common-emitter (C-E) configuration. The collector supply is 8V and the voltage drop across a resistor of 800 Ω in the collector circuit is 0.5V. If the current gain factor (α) is 0.96, find the base current.
Answer» A transistor is connected in common-emitter (C-E) configuration. The collector supply is 8V and the voltage drop across a resistor of 800 $Ω$ in the collector circuit is 0.5V. If the current gain factor $(α)$ is 0.96, find the base current.

Discussion

2.	A point charge q is placed at a distance r from the centre O of a uncharged spherical conducting shell of inner radius R and outer radius 2R. The distance r<R. The electric potential at the centre of the shell will be
Answer» A point charge $q$ is placed at a distance $r$ from the centre $O$ of a uncharged spherical conducting shell of inner radius $R$ and outer radius $2 R$ . The distance $r < R$ . The electric potential at the centre of the shell will be

Discussion

3.	Tangential acceleration of a particle moving in a circle of radius 1 m varies with time t as shown in figure (initial velocity of particle is zero). Time after which total acceleration of the particle makes an angle of 30∘ with radial acceleration is:
Answer» Tangential acceleration of a particle moving in a circle of radius $1 m$ varies with time t as shown in figure (initial velocity of particle is zero). Time after which total acceleration of the particle makes an angle of $30^{\circ}$ with radial acceleration is:

Discussion

4.	Two vectors have magnitudes 3 units and 4 units respectively. What should be the angle between them if the magnitude of the resultant is 5 units?
Answer» Two vectors have magnitudes $3$ units and $4$ units respectively. What should be the angle between them if the magnitude of the resultant is $5$ units?

Discussion

5.	The ratio of electric field at a point A and at point B due to the uniformly charged spherical conductor as shown, is
Answer» The ratio of electric field at a point A and at point B due to the uniformly charged spherical conductor as shown, is

5.

The ratio of electric field at a point A and at point B due to the uniformly charged spherical conductor as shown, is

Answer»

The ratio of electric field at a point A and at point B due to the uniformly charged spherical conductor as shown, is

Discussion

6.	From a uniform circular disc of radius 20 cm, two small circular discs of radius 10 cm are removed in such a way that both have common tangent as shown in the figure given below. The distance of centre of mass of the remaining part from the centre of original disc is:
Answer» From a uniform circular disc of radius $20 cm$ , two small circular discs of radius $10 cm$ are removed in such a way that both have common tangent as shown in the figure given below. The distance of centre of mass of the remaining part from the centre of original disc is:

Discussion

7.	Two bodies of masses of 1 kg and 3 kg initially at rest are moving with velocities 30 m/s and 10 m/s towards each other due to mutual force of attraction. What is the velocity of the centre of mass of system?
Answer» Two bodies of masses of $1 kg$ and $3 kg$ initially at rest are moving with velocities $30 m/s$ and $10 m/s$ towards each other due to mutual force of attraction. What is the velocity of the centre of mass of system?

Discussion

8.	A smooth wire of length 2πr is bent into a circle and kept in a vertical plane. A bead can slide smoothly on the wire. When the circlular frame is rotating with angular speed ω about the vertical diameter AB, the bead is at rest with respect to the circular frame at the position shown in the figure. Then, the value of ω2 is equal to:
Answer» A smooth wire of length $2 π r$ is bent into a circle and kept in a vertical plane. A bead can slide smoothly on the wire. When the circlular frame is rotating with angular speed $ω$ about the vertical diameter $A B$ , the bead is at rest with respect to the circular frame at the position shown in the figure. Then, the value of $ω^{2}$ is equal to:

Discussion

9.	In a radioactive decay chain, 23290Th nucleus decays to 21282Pb nucleus. Let Nα and Nβ be the number of α and β− particles respectively, emitted in this decay process. Which of the following statements is (are) true?
Answer» In a radioactive decay chain, $_{90}^{232} T h$ nucleus decays to $_{82}^{212} P b$ nucleus. Let $N_{α}$ and $N_{β}$ be the number of α and $β^{-}$ particles respectively, emitted in this decay process. Which of the following statements is (are) true?

Discussion

10.	A system of smooth hollow cylinder and block was initially at rest as shown. If cylinder is given constant acceleration 2g in horizontal direction, then the maximum angular displacement of the block with the vertical is:
Answer» A system of smooth hollow cylinder and block was initially at rest as shown. If cylinder is given constant acceleration 2g in horizontal direction, then the maximum angular displacement of the block with the vertical is:

Discussion

11.	A solid cylinder is performing pure rolling motion on a moving platform as shown. Which of the relation between, v0,ω,R and v is correct?
Answer» A solid cylinder is performing pure rolling motion on a moving platform as shown. Which of the relation between, $v_{0}, ω, R$ and v is correct?

Discussion

12.	If y=1+x−x22!−x33!+x44!+x55!−........ then dydx=
Answer» If $y = 1 + x - \frac{x^{2}}{2!} - \frac{x^{3}}{3!} + \frac{x^{4}}{4!} + \frac{x^{5}}{5!} - . . . . . . . .$ then $\frac{d y}{d x} =$

Discussion

13.	At what temperature is the kinetic energy of a gas molecule half of its value at 327∘ C?
Answer» At what temperature is the kinetic energy of a gas molecule half of its value at $327^{\circ} C$ ?

Discussion

14.	A rod is measured at 10∘C using a scale calibrated at that temperature. Find the percentage error in length, if thermal coefficients of linear expansion of the rod and scale are 3×10−5/∘C and 2×10−5/∘C respectively, and the rod is measured at 50∘C.
Answer» A rod is measured at $10^{\circ} C$ using a scale calibrated at that temperature. Find the percentage error in length, if thermal coefficients of linear expansion of the rod and scale are $3 \times 10^{- 5} /^{\circ} C$ and $2 \times 10^{- 5} /^{\circ} C$ respectively, and the rod is measured at $50^{\circ} C$ .

Discussion

15.	A particle is moving along x-axis and velocity 'v' vs 'x' graph of particle is as shown in the figure, where x is the displacement of the particle. Find \|a1a2\|, where a1 and a2 are accelerations at points 1 and 2 respectively.
Answer» A particle is moving along x-axis and velocity ' $v$ ' vs ' $x$ ' graph of particle is as shown in the figure, where $x$ is the displacement of the particle. Find $\| \frac{a_{1}}{a_{2}} \|$ , where $a_{1}$ and $a_{2}$ are accelerations at points 1 and 2 respectively.

Discussion

16.	A block of mass 10 kg is kept on an inclined plane having an angle of inclination 37∘ attached with a spring of force constant 20 N/m as shown in the figure. If the coefficient of friction between block and incline is 0.8, then the maximum value of elongation for which the block is in contact with the inclined plane and has no slipping is
Answer» A block of mass $10 k g$ is kept on an inclined plane having an angle of inclination $37^{\circ}$ attached with a spring of force constant $20 N / m$ as shown in the figure. If the coefficient of friction between block and incline is $0.8$ , then the maximum value of elongation for which the block is in contact with the inclined plane and has no slipping is

Discussion

17.	When 300 J of heat is added to 25 gm of sample of a material its temperature rises from 25∘C to 45∘C. the thermal capacity of the sample and specific heat of the material are respectively given by
Answer» When 300 J of heat is added to 25 gm of sample of a material its temperature rises from $25^{\circ} C t o 45^{\circ} C .$ the thermal capacity of the sample and specific heat of the material are respectively given by

Discussion

18.	If μ1 and μ2 are the refractive indices of the materials of core and cladding of an optical fibers respectively, then the loss of light due to its leakage can be minimised by having:
Answer» If $μ_{1}$ and $μ_{2}$ are the refractive indices of the materials of core and cladding of an optical fibers respectively, then the loss of light due to its leakage can be minimised by having:

Discussion

19.	The work done in pulling up a block of wood weighing 2kN for a length of 10 m on a smooth plane inclined at an angle of 15∘with the horizontal is (sin15∘=0.259)
Answer» The work done in pulling up a block of wood weighing 2kN for a length of 10 m on a smooth plane inclined at an angle of $15^{\circ}$ with the horizontal is $(s i n 15^{\circ} = 0.259)$

19.

The work done in pulling up a block of wood weighing 2kN for a length of 10 m on a smooth plane inclined at an angle of 15∘with the horizontal is (sin15∘=0.259)

Answer»

The work done in pulling up a block of wood weighing 2kN for a length of 10 m on a smooth plane inclined at an angle of $15^{\circ}$ with the horizontal is $(s i n 15^{\circ} = 0.259)$

Discussion

20.	A point object having charge q and mass m kept on the top of a frictionless and insulated hemisphere. When a horizontal electric field is applied, the object starts sliding down and loses contact from the surface at an angle θ=sin−135 from the vertical. The ratio of force of gravity and the force due to interaction with the field acting on this object is
Answer» A point object having charge $q$ and mass $m$ kept on the top of a frictionless and insulated hemisphere. When a horizontal electric field is applied, the object starts sliding down and loses contact from the surface at an angle $θ = s i n^{- 1} \frac{3}{5}$ from the vertical. The ratio of force of gravity and the force due to interaction with the field acting on this object is

Discussion

21.	A cylindrical vessel with a cross sectional area A has a small hole of area a at the bottom. A liquid is filled in the vessel upto a height H. Find the time taken to empty the tank.
Answer» A cylindrical vessel with a cross sectional area $A$ has a small hole of area $a$ at the bottom. A liquid is filled in the vessel upto a height $H$ . Find the time taken to empty the tank.

Discussion

22.	A hollow sphere of mass M=50 kg and radius r=(340π)13m is immersed in a tank of water (density ρw=103 kg/m3). The sphere is tied to the bottom of a tank by two wires A and B as shown. Tension in wire A is (g=10 m/s2)
Answer» A hollow sphere of mass $M = 50 kg$ and radius $r = {(\frac{3}{40 π})}^{\frac{1}{3}} m$ is immersed in a tank of water (density $ρ_{w} = 10^{3} {kg/m}^{3})$ . The sphere is tied to the bottom of a tank by two wires $A$ and $B$ as shown. Tension in wire $A$ is $(g = 10 {m/s}^{2})$

Discussion

23.	In the circuit shown in figure current in the circuit is
Answer» In the circuit shown in figure current in the circuit is

Discussion

24.	Three identical bulbs P, Q and R are connected to a battery as shown in figure. When the circuit is closed
Answer» Three identical bulbs P, Q and R are connected to a battery as shown in figure. When the circuit is closed

Discussion

25.	A magnet makes 40 oscillations per minute at a place having magnetic field intensity of 1×10−6 T. At another place, it takes 3 seconds to complete one vibration. The value of the earth's horizontal field at that place is (Neglect gravitational effect)
Answer» A magnet makes 40 oscillations per minute at a place having magnetic field intensity of $1 \times 10^{- 6} T$ . At another place, it takes 3 seconds to complete one vibration. The value of the earth's horizontal field at that place is (Neglect gravitational effect)

Discussion

26.	A ball of mass m and radius r is released in a viscous liquid. The value of its terminal velocity is proportional to
Answer» A ball of mass $m$ and radius $r$ is released in a viscous liquid. The value of its terminal velocity is proportional to

Discussion

27.	If a body of mass 'm' is moving on a rough horizontal surface of coefficient of kinetic friction, μ, the net electromagnetic force exerted by surface on the body is
Answer» If a body of mass 'm' is moving on a rough horizontal surface of coefficient of kinetic friction, μ, the net electromagnetic force exerted by surface on the body is

Discussion

28.	Two uniform rings of same radius r and mass m are placed such that their centres are at a common point and their planes are perpendicular to each other. The moment of inertia of the system about an axis passing through the centres and perpendicular to plane of one of the rings is:
Answer» Two uniform rings of same radius $r$ and mass $m$ are placed such that their centres are at a common point and their planes are perpendicular to each other. The moment of inertia of the system about an axis passing through the centres and perpendicular to plane of one of the rings is:

Discussion

29.	A horizontal platform with an object placed on it is executing S.H.M. in the vertical direction. The amplitude of oscillation is 3.92×10−3 m. What should be the least period of these oscillations, so that the object is not detached from the platform ?
Answer» A horizontal platform with an object placed on it is executing S.H.M. in the vertical direction. The amplitude of oscillation is $3.92 \times 10^{- 3} m .$ What should be the least period of these oscillations, so that the object is not detached from the platform ?

Discussion

30.	Figure shows the behaviour of light rays with respect to a thin plano-convex lens whose plane surface is silvered as shown in the figure. If the refractive index of the material of the lens is 1.5. choose the correct option(s).
Answer» Figure shows the behaviour of light rays with respect to a thin plano-convex lens whose plane surface is silvered as shown in the figure. If the refractive index of the material of the lens is 1.5. choose the correct option(s).

30.

Figure shows the behaviour of light rays with respect to a thin plano-convex lens whose plane surface is silvered as shown in the figure. If the refractive index of the material of the lens is 1.5. choose the correct option(s).

Answer»

Figure shows the behaviour of light rays with respect to a thin plano-convex lens whose plane surface is silvered as shown in the figure. If the refractive index of the material of the lens is 1.5. choose the correct option(s).

Discussion

31.	A particle having specific charge C starts from rest in a region where the electric field has a constant direction but varying with time as E=E0t2 in magnitude. Further, it is observed that the particle has acquired a velocity V after covering a distance x.Then
Answer» A particle having specific charge $C$ starts from rest in a region where the electric field has a constant direction but varying with time as $E = E_{0} t^{2}$ in magnitude. Further, it is observed that the particle has acquired a velocity $V$ after covering a distance $x$ .Then

Discussion

32.	Two wires P and Q of same cross-sectional area A=10mm2 and the same length l0=1 m but made of different materials are joined together and their ends are rigidly clamp between two walls with negligible tension. Their respective Young's modulus and the coefficients of linear expansion are Y1,α1 and Y2,α2 respectively. Given Y1=2×109N/m2,α1=3×10−4/∘C,Y2=109N/m2,α2=6×10−4/∘C, If the temperature of system is reduced by 20∘C the tension developed in wire P is
Answer» Two wires P and Q of same cross-sectional area $A = 10 m m^{2}$ and the same length $l_{0} = 1$ m but made of different materials are joined together and their ends are rigidly clamp between two walls with negligible tension. Their respective Young's modulus and the coefficients of linear expansion are $Y_{1}, α_{1}$ and $Y_{2}, α_{2}$ respectively. Given $Y_{1} = 2 \times 10^{9} N / m^{2}, α_{1} = 3 \times 10^{- 4} /^{\circ} C, Y_{2} = 10^{9} N / m^{2}, α_{2} = 6 \times 10^{- 4} /^{\circ} C$ , If the temperature of system is reduced by $20^{\circ} C$ the tension developed in wire P is

32.

Two wires P and Q of same cross-sectional area A=10mm2 and the same length l0=1 m but made of different materials are joined together and their ends are rigidly clamp between two walls with negligible tension. Their respective Young's modulus and the coefficients of linear expansion are Y1,α1 and Y2,α2 respectively. Given Y1=2×109N/m2,α1=3×10−4/∘C,Y2=109N/m2,α2=6×10−4/∘C, If the temperature of system is reduced by 20∘C the tension developed in wire P is

Answer»

Two wires P and Q of same cross-sectional area $A = 10 m m^{2}$ and the same length $l_{0} = 1$ m but made of different materials are joined together and their ends are rigidly clamp between two walls with negligible tension. Their respective Young's modulus and the coefficients of linear expansion are $Y_{1}, α_{1}$ and $Y_{2}, α_{2}$ respectively.
Given $Y_{1} = 2 \times 10^{9} N / m^{2}, α_{1} = 3 \times 10^{- 4} /^{\circ} C, Y_{2} = 10^{9} N / m^{2}, α_{2} = 6 \times 10^{- 4} /^{\circ} C$ ,

If the temperature of system is reduced by $20^{\circ} C$ the tension developed in wire P is

Discussion

33.	A compound contains 6.4% by mass of oxygen. It contains two moles of oxygen per mole of the compound. What is the molar mass of the compound?
Answer» A compound contains $6.4 %$ by mass of oxygen. It contains two moles of oxygen per mole of the compound. What is the molar mass of the compound?

Discussion

34.	The following pictograph shows the number of oranges sold in the following weeks. How many oranges were sold in Week 1?
Answer» The following pictograph shows the number of oranges sold in the following weeks. How many oranges were sold in Week 1?

Discussion

35.	Calculate the reduced mass of HCl molecule. Given that the mass of H atom is 1.0078 amu and the mass of Cl atom is 34.9688 amu. Note that 1 amu=1.660565×10−27kg.
Answer» Calculate the reduced mass of $H C l$ molecule. Given that the mass of $H$ atom is $1.0078 amu$ and the mass of Cl atom is $34.9688 amu$ . Note that $1 amu = 1.660565 \times 10^{- 27} kg$ .

Discussion

36.	A river 400 m wide is flowing at a rate of 2.0 m/s. A boat is sailing at a velocity of 10.0 m/s with respect to the water, in a direction perpendicular to the river. Find the time taken by the boat to reach the opposite bank.
Answer» A river $400 m$ wide is flowing at a rate of $2.0 m / s$ . A boat is sailing at a velocity of $10.0 m / s$ with respect to the water, in a direction perpendicular to the river. Find the time taken by the boat to reach the opposite bank.

Discussion

37.	The mass of an iron cube having an edge length 1.5 cm is 50 g. Find its density.
Answer» The mass of an iron cube having an edge length 1.5 cm is 50 g. Find its density.

Discussion

38.	In a uniform electric field, an electric dipole experiences only torque. But when the electric field is non-uniform, it experiences torque as well as a net force. Why is it so?
Answer» In a uniform electric field, an electric dipole experiences only torque. But when the electric field is non-uniform, it experiences torque as well as a net force. Why is it so?

Discussion

39.	UV light of wavelength 271 amstrong from a 100 W mercury source eradiates a photocell made of molybdenum metal . If stopping potential is -1.3V estimate work function of the metal. How would the photocell respond to a high intensity (10 power 5 watt per meter square ) red light of wavelength 6328 amstrong produced by helium neon laser ?
Answer» UV light of wavelength 271 amstrong from a 100 W mercury source eradiates a photocell made of molybdenum metal . If stopping potential is -1.3V estimate work function of the metal. How would the photocell respond to a high intensity (10 power 5 watt per meter square ) red light of wavelength 6328 amstrong produced by helium neon laser ?

Discussion

40.	Consider a car moving along a straight horizontal road with a speed of 72 kmph. If the coefficient of static friction between the tyres and the road is 0.5, the shortest distance in which the car can be stopped is (Take g=10ms2)
Answer» Consider a car moving along a straight horizontal road with a speed of $72 k m p h$ . If the coefficient of static friction between the tyres and the road is $0.5$ , the shortest distance in which the car can be stopped is $(Take g = 10 \frac{m}{s^{2}})$

Discussion

41.	Does the rhydberg constant have two values one for H and second one for other elements? If yes, what are the dimensions of both?
Answer» Does the rhydberg constant have two values one for H and second one for other elements? If yes, what are the dimensions of both?

Discussion

42.	An air bubble of radius 2.0 mm is formed at the bottom of a 3.3 m deep river. Calculate the radius of the bubble as it comes to the surface. Atmospheric pressure =1.0×105 Pa and density of water =1000 kg m−3
Answer» An air bubble of radius 2.0 mm is formed at the bottom of a 3.3 m deep river. Calculate the radius of the bubble as it comes to the surface. Atmospheric pressure $= 1.0 \times 10^{5}$ Pa and density of water $= 1000 k g m^{- 3}$

Discussion

43.	A block of mass 10 kg is pulled at constant speed on a rough horizontal surface by a force of 19.6 N. The coefficient of friction is
Answer» A block of mass $10 k g$ is pulled at constant speed on a rough horizontal surface by a force of $19.6 N$ . The coefficient of friction is

Discussion

44.	In column 1 different setup for Young’s double slit experiment is given. Distance between two slits S1 and S2 is ‘d’ and between slits and screen is ‘D’ in every setup. In column 2 location of central maxima is given. In column 3 path difference ΔP is given at point P which is θ angle above MO line (d << D) Mark the correct combination
Answer» In column 1 different setup for Young’s double slit experiment is given. Distance between two slits S1 and S2 is ‘d’ and between slits and screen is ‘D’ in every setup. In column 2 location of central maxima is given. In column 3 path difference $Δ P$ is given at point P which is $θ$ angle above MO line (d << D) Mark the correct combination

Discussion

45.	A ball is launched from the top of Mt. Everest which is at elevation of 9000 m. The ball moves in circular orbit around earth. Acceleration due to gravity near the earth’s surface is g. The magnitude of the ball’s acceleration while in orbit is
Answer» A ball is launched from the top of Mt. Everest which is at elevation of 9000 m. The ball moves in circular orbit around earth. Acceleration due to gravity near the earth’s surface is g. The magnitude of the ball’s acceleration while in orbit is

Discussion

46.	A parallel plate capacitor with air between its plates is charged using a battery and then disconnected from the battery. Column-IColumn-IIA. Potential difference between the plates will(p) Separation between the plates is increased byK2(K>2) decrease iftimes the initial value and space between the platesafter the separation has increased, is completelyfilled with a dielectric (here K is the dielectric constantB. Electric field strength between the plates will reduce if(q) Separation between the plates is increasedC. Electric energy stored in the capacitor will decrease if(r)A dielectric with K>1 is filled between plates of the capacitorD. Electric energy density will decrease if(s) Separation between the plates is reduced(t) None
Answer» A parallel plate capacitor with air between its plates is charged using a battery and then disconnected from the battery. $\begin{matrix} Column-I & Column-II A. Potential difference between the plates will & (p) Separation between the plates is increased by \frac{K}{2} (K > 2) decrease if & times the initial value and space between the plates after the separation has increased, is completely filled with a dielectric (here K is the dielectric constant B. Electric field strength between the plates will reduce if & (q) Separation between the plates is increased C. Electric energy stored in the capacitor will decrease if & (r)A dielectric with K > 1 is filled between plates of the capacitor D. Electric energy density will decrease if & (s) Separation between the plates is reduced (t) None \end{matrix}$

Discussion

47.	In the given arrangement, n number of equal masses are connected by strings of negligible masses. The tension in the string connected to nth mass is
Answer» In the given arrangement, $n$ number of equal masses are connected by strings of negligible masses. The tension in the string connected to $n^{t h}$ mass is

Discussion

48.	The steam point and the ice point of a mercury thermometer are marked as 80∘ and 20∘. What will be the temperature in centigrade mercury scale when this thermometer reads 32∘ ?
Answer» The steam point and the ice point of a mercury thermometer are marked as $80^{\circ}$ and $20^{\circ}$ . What will be the temperature in centigrade mercury scale when this thermometer reads $32^{\circ}$ ?

Discussion

49.	Find the acceleration of the 500 g block in figure.
Answer» Find the acceleration of the 500 g block in figure.

49.

Find the acceleration of the 500 g block in figure.

Answer»

Find the acceleration of the 500 g block in figure.

Discussion

50.	A concave mirror forms an image of 20 cm high object on a screen placed 5.0 m away from the mirror. The height of the image is 50 cm. Find the focal length of the mirror and the distance between the mirror and the object.
Answer» A concave mirror forms an image of 20 cm high object on a screen placed 5.0 m away from the mirror. The height of the image is 50 cm. Find the focal length of the mirror and the distance between the mirror and the object.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A transistor is connected in common-emitter (C-E) configuration. The collector supply is 8V and the voltage drop across a resistor of 800 Ω in the collector circuit is 0.5V. If the current gain factor (α) is 0.96, find the base current.

A point charge q is placed at a distance r from the centre O of a uncharged spherical conducting shell of inner radius R and outer radius 2R. The distance r&lt;R. The electric potential at the centre of the shell will be

Tangential acceleration of a particle moving in a circle of radius 1 m varies with time t as shown in figure (initial velocity of particle is zero). Time after which total acceleration of the particle makes an angle of 30∘ with radial acceleration is:

Two vectors have magnitudes 3 units and 4 units respectively. What should be the angle between them if the magnitude of the resultant is 5 units?

The ratio of electric field at a point A and at point B due to the uniformly charged spherical conductor as shown, is

From a uniform circular disc of radius 20 cm, two small circular discs of radius 10 cm are removed in such a way that both have common tangent as shown in the figure given below. The distance of centre of mass of the remaining part from the centre of original disc is:

Two bodies of masses of 1 kg and 3 kg initially at rest are moving with velocities 30 m/s and 10 m/s towards each other due to mutual force of attraction. What is the velocity of the centre of mass of system?

In a radioactive decay chain, ​23290Th nucleus decays to 21282Pb nucleus. Let Nα ​ and Nβ ​ be the number of α and β− particles respectively, emitted in this decay process. Which of the following statements is (are) true?

A system of smooth hollow cylinder and block was initially at rest as shown. If cylinder is given constant acceleration 2g in horizontal direction, then the maximum angular displacement of the block with the vertical is:

A solid cylinder is performing pure rolling motion on a moving platform as shown. Which of the relation between, v0,ω,R and v is correct?

If y=1+x−x22!−x33!+x44!+x55!−........ then dydx=

At what temperature is the kinetic energy of a gas molecule half of its value at 327∘ C?

A rod is measured at 10∘C using a scale calibrated at that temperature. Find the percentage error in length, if thermal coefficients of linear expansion of the rod and scale are 3×10−5/∘C and 2×10−5/∘C respectively, and the rod is measured at 50∘C.

A particle is moving along x-axis and velocity 'v' vs 'x' graph of particle is as shown in the figure, where x is the displacement of the particle. Find |a1a2|, where a1 and a2 are accelerations at points 1 and 2 respectively.

When 300 J of heat is added to 25 gm of sample of a material its temperature rises from 25∘C to 45∘C. the thermal capacity of the sample and specific heat of the material are respectively given by

If μ1 and μ2 are the refractive indices of the materials of core and cladding of an optical fibers respectively, then the loss of light due to its leakage can be minimised by having:

The work done in pulling up a block of wood weighing 2kN for a length of 10 m on a smooth plane inclined at an angle of 15∘with the horizontal is (sin15∘=0.259)

A cylindrical vessel with a cross sectional area A has a small hole of area a at the bottom. A liquid is filled in the vessel upto a height H. Find the time taken to empty the tank.

A hollow sphere of mass M=50 kg and radius r=(340π)13m is immersed in a tank of water (density ρw=103 kg/m3). The sphere is tied to the bottom of a tank by two wires A and B as shown. Tension in wire A is (g=10 m/s2)

In the circuit shown in figure current in the circuit is

Three identical bulbs P, Q and R are connected to a battery as shown in figure. When the circuit is closed

A magnet makes 40 oscillations per minute at a place having magnetic field intensity of 1×10−6 T. At another place, it takes 3 seconds to complete one vibration. The value of the earth's horizontal field at that place is (Neglect gravitational effect)

A ball of mass m and radius r is released in a viscous liquid. The value of its terminal velocity is proportional to

If a body of mass 'm' is moving on a rough horizontal surface of coefficient of kinetic friction, μ, the net electromagnetic force exerted by surface on the body is

Two uniform rings of same radius r and mass m are placed such that their centres are at a common point and their planes are perpendicular to each other. The moment of inertia of the system about an axis passing through the centres and perpendicular to plane of one of the rings is:

A horizontal platform with an object placed on it is executing S.H.M. in the vertical direction. The amplitude of oscillation is 3.92×10−3 m. What should be the least period of these oscillations, so that the object is not detached from the platform ?

Figure shows the behaviour of light rays with respect to a thin plano-convex lens whose plane surface is silvered as shown in the figure. If the refractive index of the material of the lens is 1.5. choose the correct option(s).

A particle having specific charge C starts from rest in a region where the electric field has a constant direction but varying with time as E=E0t2 in magnitude. Further, it is observed that the particle has acquired a velocity V after covering a distance x.Then

A compound contains 6.4% by mass of oxygen. It contains two moles of oxygen per mole of the compound. What is the molar mass of the compound?

The following pictograph shows the number of oranges sold in the following weeks. How many oranges were sold in Week 1?

Calculate the reduced mass of HCl molecule. Given that the mass of H atom is 1.0078 amu and the mass of Cl atom is 34.9688 amu. Note that 1 amu=1.660565×10−27kg.

A river 400 m wide is flowing at a rate of 2.0 m/s. A boat is sailing at a velocity of 10.0 m/s with respect to the water, in a direction perpendicular to the river. Find the time taken by the boat to reach the opposite bank.

The mass of an iron cube having an edge length 1.5 cm is 50 g. Find its density.

In a uniform electric field, an electric dipole experiences only torque. But when the electric field is non-uniform, it experiences torque as well as a net force. Why is it so?

Consider a car moving along a straight horizontal road with a speed of 72 kmph. If the coefficient of static friction between the tyres and the road is 0.5, the shortest distance in which the car can be stopped is (Take g=10ms2)

Does the rhydberg constant have two values one for H and second one for other elements? If yes, what are the dimensions of both?

An air bubble of radius 2.0 mm is formed at the bottom of a 3.3 m deep river. Calculate the radius of the bubble as it comes to the surface. Atmospheric pressure =1.0×105 Pa and density of water =1000 kg m−3

A block of mass 10 kg is pulled at constant speed on a rough horizontal surface by a force of 19.6 N. The coefficient of friction is

A ball is launched from the top of Mt. Everest which is at elevation of 9000 m. The ball moves in circular orbit around earth. Acceleration due to gravity near the earth’s surface is g. The magnitude of the ball’s acceleration while in orbit is

In the given arrangement, n number of equal masses are connected by strings of negligible masses. The tension in the string connected to nth mass is

The steam point and the ice point of a mercury thermometer are marked as 80∘ and 20∘. What will be the temperature in centigrade mercury scale when this thermometer reads 32∘ ?

Find the acceleration of the 500 g block in figure.

A concave mirror forms an image of 20 cm high object on a screen placed 5.0 m away from the mirror. The height of the image is 50 cm. Find the focal length of the mirror and the distance between the mirror and the object.

A point charge q is placed at a distance r from the centre O of a uncharged spherical conducting shell of inner radius R and outer radius 2R. The distance r<R. The electric potential at the centre of the shell will be

In a radioactive decay chain, 23290Th nucleus decays to 21282Pb nucleus. Let Nα and Nβ be the number of α and β− particles respectively, emitted in this decay process. Which of the following statements is (are) true?