50278 + Interview Questions in Physics

1.	A cylinder of ideal gas is closed by an 8 kg movable piston (area 60 cm2). Atmospheric pressure is 105 Pa. When the gas is heated from 30°C to 100°C, the piston rises by 20 cm. The piston is then fixed in its place and the gas is cooled back to 30°C. Let ΔQ1 be the heat added to the gas in the heating process and \|ΔQ2\| the heat lost during cooling. Then the value of ΔQ1−\|ΔQ2\| will be
Answer» A cylinder of ideal gas is closed by an $8 k g$ movable piston (area $60 c m^{2}$ ). Atmospheric pressure is $10^{5} P a$ . When the gas is heated from $30 ° C$ to $100 ° C$ , the piston rises by $20 c m$ . The piston is then fixed in its place and the gas is cooled back to $30 ° C$ . Let $Δ Q_{1}$ be the heat added to the gas in the heating process and $\| Δ Q_{2} \|$ the heat lost during cooling. Then the value of $Δ Q_{1} - \| Δ Q_{2} \|$ will be

Discussion

2.	A whistle revolves in a circle with angular velocity ω=20 rad/s using a string of length 50 cm. If the actual frequency of sound from the whistle is 385 Hz, then the minimum frequency heard by the observer far away from the centre is (velocity of sound v=340 m/s)
Answer» A whistle revolves in a circle with angular velocity $ω = 20 r a d / s$ using a string of length $50 c m$ . If the actual frequency of sound from the whistle is $385 H z$ , then the minimum frequency heard by the observer far away from the centre is (velocity of sound $v = 340 m / s$ )

Discussion

3.	A uniform electric field pointing in positive x-direction exists in a region. Let A be the origin, B be the point on the x-axis at x = +1 cm and C be the point on the y-axis at y = +1 cm. Then the potentials at the points A, B and C satisfy
Answer» A uniform electric field pointing in positive x-direction exists in a region. Let A be the origin, B be the point on the x-axis at x = +1 cm and C be the point on the y-axis at y = +1 cm. Then the potentials at the points A, B and C satisfy

Discussion

4.	A block of mass 1 kg is at rest relative to a smooth wedge moving leftwards with constant acceleration a=5 m/ s2. Let N be the normal reaction between the block and the wedge. Then (g=10 m/s2)
Answer» A block of mass $1 kg$ is at rest relative to a smooth wedge moving leftwards with constant acceleration $a = 5 {m/ s}^{2}$ . Let $N$ be the normal reaction between the block and the wedge. Then $(g = 10 {m/s}^{2}$ )

Discussion

5.	A piece of solid weighs 120 g in air and 80 g when completely immersed in water. The relative density of solid is
Answer» A piece of solid weighs $120 g$ in air and $80 g$ when completely immersed in water. The relative density of solid is

Discussion

6.	A stone is projected from the ground. Its path is as shown in the figure. At which point is its speed decreasing at the fastest rate?
Answer» A stone is projected from the ground. Its path is as shown in the figure. At which point is its speed decreasing at the fastest rate?

Discussion

7.	A particle of mass 0.2 kg (initially at rest) starts moving in one dimension under a force that delivers a constant power 0.5 W to the particle. Then the speed after 5 seconds is
Answer» A particle of mass $0.2 kg$ (initially at rest) starts moving in one dimension under a force that delivers a constant power $0.5 W$ to the particle. Then the speed after $5 seconds$ is

Discussion

8.	A body is projected from the top of a tower of height 32 m with a velocity of 20 m/s at an angle of 37∘ above the horizontal. The time of flight of the projectile (in seconds) is
Answer» A body is projected from the top of a tower of height $32 m$ with a velocity of $20 m/s$ at an angle of $37^{\circ}$ above the horizontal. The time of flight of the projectile (in seconds) is

Discussion

9.	Three blocks A, B and C of masses 2 kg,3 kg and 4 kg are placed as shown. Coefficient of friction between A and B is 0.5 and that between B and C is 0.1. The surface is frictionless. The maximum force F in N that can be applied horizontally onto A such that the three blocks move together is (Answer upto 2 decimal places and take g=10 ms−2 )
Answer» Three blocks A, B and C of masses $2 kg, 3 kg$ and $4 kg$ are placed as shown. Coefficient of friction between A and B is 0.5 and that between B and C is 0.1. The surface is frictionless. The maximum force $F$ in N that can be applied horizontally onto A such that the three blocks move together is (Answer upto 2 decimal places and take $g = 10 m s^{- 2}$ )

Discussion

10.	A wooden ball of density D is immersed in water of density d to a depth h below the surface of water and then released. Upto what height will the ball jump out of water( measured from surface of water) ?
Answer» A wooden ball of density $D$ is immersed in water of density $d$ to a depth $h$ below the surface of water and then released. Upto what height will the ball jump out of water( measured from surface of water) ?

Discussion

11.	How much heat must be removed by a refrigerator from 4 kg of water at 70∘C to convert it to ice cube at −10∘C ? [Take specific heat of water Cw=4200 J/kg/∘C, Latent heat of fusion of iceLf=334000 J/kg, Specific heat of ice Ci=2100 J/kg K]
Answer» How much heat must be removed by a refrigerator from $4 kg$ of water at $70^{\circ} C$ to convert it to ice cube at $- 10^{\circ} C$ ? [Take specific heat of water $C_{w} = 4200 {J/kg/}^{\circ} C$ , Latent heat of fusion of ice $L_{f} = 334000 J/kg$ , Specific heat of ice $C_{i} = 2100 J/kg K$ ]

Discussion

12.	When you put an object on a spring balance, you get
Answer» When you put an object on a spring balance, you get

Discussion

13.	A parallel-plate capacitor having plate area 25 cm2 and separation 1.00 mm is connected to a batter of 6.0 V. Calculate the charge flown through the battery. How much work has been done by the battery during the process ?
Answer» A parallel-plate capacitor having plate area $25 c m^{2}$ and separation 1.00 mm is connected to a batter of 6.0 V. Calculate the charge flown through the battery. How much work has been done by the battery during the process ?

Discussion

14.	A wheel of moment of inertia 0.10 kg-m2 is rotating about a shaft at an angular speed of 160 rev/minute. A second wheel is set into rotation at 300 rev/minute and is coupled to the same shaft so that both the wheels finally rotate with a common angular speed of 200 rev/minute. Find the moment of inertia of the second wheel.
Answer» A wheel of moment of inertia 0.10 ${kg-m}^{2}$ is rotating about a shaft at an angular speed of 160 rev/minute. A second wheel is set into rotation at 300 rev/minute and is coupled to the same shaft so that both the wheels finally rotate with a common angular speed of 200 rev/minute. Find the moment of inertia of the second wheel.

Discussion

15.	define retardation
Answer» define retardation

Discussion

16.	A body at rest may have
Answer» A body at rest may have

Discussion

17.	By use of a suitable filter, the green mercury emission line can be isolated. This line has a wavelength of 546.1 nm. What is the frequency? [1 Hz = 1 s-1]
Answer» By use of a suitable filter, the green mercury emission line can be isolated. This line has a wavelength of 546.1 nm. What is the frequency? [1 Hz = 1 s^-1]

Discussion

18.	A car travels the first half distance with constant velocity of 40 kmph and the remaining half with a constant velocity of 60 kmph. The average velocity of the car in kmph is
Answer» A car travels the first half distance with constant velocity of $40 k m p h$ and the remaining half with a constant velocity of $60 k m p h$ . The average velocity of the car in $k m p h$ is

Discussion

19.	Consider the general motion of a wheel of radius 2 m which can be viewed as pure translation with the velocity →v and pure rotation about O with angular velocity 5 rad/s. Which of the following is incorrect?
Answer» Consider the general motion of a wheel of radius $2 m$ which can be viewed as pure translation with the velocity $\to v$ and pure rotation about $O$ with angular velocity $5 rad/s$ . Which of the following is incorrect?

Discussion

20.	Derive the kinematic equations of motion.
Answer» Derive the kinematic equations of motion.

Discussion

21.	A body of mass m moving with a speed v suffers an inelastic collision with another body of M at rest and sticks to it, the ratio of the final kinetic energy of the system to the initial kinetic energy is
Answer» A body of mass m moving with a speed v suffers an inelastic collision with another body of M at rest and sticks to it, the ratio of the final kinetic energy of the system to the initial kinetic energy is

Discussion

22.	The initial pressure & volume of a given mass of gas (CPCV=53) are P0 and V0. The gas can exchange heat with the surroundings. It is slowly compressed to volume V04 and then suddenly compressed to volume V08 and then again slowly compressed to V016. Find the final pressure.
Answer» The initial pressure & volume of a given mass of gas $(\frac{C_{P}}{C_{V}} = \frac{5}{3})$ are $P_{0}$ and $V_{0}$ . The gas can exchange heat with the surroundings. It is slowly compressed to volume $\frac{V_{0}}{4}$ and then suddenly compressed to volume $\frac{V_{0}}{8}$ and then again slowly compressed to $\frac{V_{0}}{16}$ . Find the final pressure.

Discussion

23.	A uniform disc of diameter R/2 is put over another uniform disc of diameter R of a same thickness and density.the peripheries of the 2 discs touch each other. the centre of mass of system from centre of big disc is 1)R/10 2)R/20 3)9R/10 4)11R/10
Answer» A uniform disc of diameter R/2 is put over another uniform disc of diameter R of a same thickness and density.the peripheries of the 2 discs touch each other. the centre of mass of system from centre of big disc is 1)R/10 2)R/20 3)9R/10 4)11R/10

Discussion

24.	How many laws of reflection 2 or3
Answer» How many laws of reflection 2 or3

Discussion

25.	The velocity-time graph of a body is given in figure. The maximum acceleration in ms−2 is
Answer» The velocity-time graph of a body is given in figure. The maximum acceleration in ${ms}^{- 2}$ is

Discussion

26.	A 2 cm diameter coin rests flat on the bottom of a bowl in which the water is 20 cm deep (μw=4/3). If the coin is viewed directly from above, what is its apparent diameter?
Answer» A $2 cm$ diameter coin rests flat on the bottom of a bowl in which the water is $20 cm$ deep ( $μ_{w} = 4 / 3$ ). If the coin is viewed directly from above, what is its apparent diameter?

Discussion

27.	A vector −→F1 is along x-axis. If its vector product with another vector −→F2 is zero, then −→F2 could be
Answer» A vector $_{1}$ is along $x$ -axis. If its vector product with another vector $_{2}$ is zero, then $_{2}$ could be

Discussion

28.	A constant force F=m2g/2 is applied on the block of mass m1 as shown in figure. The string and the pulley are light and the surface of the table is smooth. Find the acceleration of m1.
Answer» A constant force $F = m_{2} g / 2$ is applied on the block of mass $m_{1}$ as shown in figure. The string and the pulley are light and the surface of the table is smooth. Find the acceleration of $m_{1}$ .

28.

A constant force F=m2g/2 is applied on the block of mass m1 as shown in figure. The string and the pulley are light and the surface of the table is smooth. Find the acceleration of m1.

Answer»

A constant force $F = m_{2} g / 2$ is applied on the block of mass $m_{1}$ as shown in figure. The string and the pulley are light and the surface of the table is smooth. Find the acceleration of $m_{1}$ .

Discussion

29.	A galvanometer (G) is shunted such that only 111th of the main current flows through it. If G=150 Ω the shunt resistance is
Answer» A galvanometer (G) is shunted such that only $\frac{1}{11}$ th of the main current flows through it. If G=150 $Ω$ the shunt resistance is

Discussion

30.	A vessel contains a mixture of one mole of oxygen and two moles of nitrogen at 300 K. The ratio of the average rotational kinetic energy per O2 molecule to that per N2 molecule is
Answer» A vessel contains a mixture of one mole of oxygen and two moles of nitrogen at 300 K. The ratio of the average rotational kinetic energy per $O_{2}$ molecule to that per $N_{2}$ molecule is

Discussion

31.	Visible light of wavelength 6000×10−8cm falls normally on a single slit and produces a diffraction pattern. It is found that the second diffraction minima is at 60o from the central maxima. If the first minimum is produced at θ1, then θ1 is close to
Answer» Visible light of wavelength $6000 \times 10^{- 8} c m$ falls normally on a single slit and produces a diffraction pattern. It is found that the second diffraction minima is at $60^{o}$ from the central maxima. If the first minimum is produced at $θ_{1}$ , then $θ_{1}$ is close to

Discussion

32.	The position of a particle is given by →r=3t^i+√3t2^j−4^k where t is in seconds and →r is meters. Find out magnitude of velocity →v and angle made by velocity →v with X-axis at t=√3 s.
Answer» The position of a particle is given by $\to r = 3 t^i + \sqrt{3} t^{2}^j - 4^k$ where $t$ is in seconds and $\to r$ is meters. Find out magnitude of velocity $\to v$ and angle made by velocity $\to v$ with X-axis at $t = \sqrt{3} s .$

Discussion

33.	The metallic bob of a simple pendulum has the relative density ρ. The time period of this pendulum is T. If the metallic bob is immersed completely in water, then the new time period is given by
Answer» The metallic bob of a simple pendulum has the relative density $ρ$ . The time period of this pendulum is $T$ . If the metallic bob is immersed completely in water, then the new time period is given by

Discussion

34.	The volume charge density as a function of distance x from one face inside a cube of side 2 m, is varying as shown in the figure. Find the total flux (in S.I. units) through the cube. (If ρ0=8.85×10−12C/m3) ___
Answer» The volume charge density as a function of distance x from one face inside a cube of side 2 m, is varying as shown in the figure. Find the total flux (in S.I. units) through the cube. (If $ρ_{0} = 8.85 \times 10^{- 12} C / m^{3}$ ) ___

Discussion

35.	A projectile is fired at an angle of 45o with the horizontal. Elevation angle of the projectile at its highest point as seen from the point of projection is
Answer» A projectile is fired at an angle of $45^{o}$ with the horizontal. Elevation angle of the projectile at its highest point as seen from the point of projection is

Discussion

36.	What is the angular velocity in rad/s of a wheel making 1200 revolutions in 50 minutes ?
Answer» What is the angular velocity in $rad/s$ of a wheel making $1200$ revolutions in $50$ minutes ?

Discussion

37.	Six moles of an ideal gas undergo a cyclic process shown in the figure. If the temperatures are given as TA=600 K, TB=800 K, TC=2200 K and TD=1200 K, then the work done per cycle is
Answer» Six moles of an ideal gas undergo a cyclic process shown in the figure. If the temperatures are given as $T_{A} = 600 K$ , $T_{B} = 800 K$ , $T_{C} = 2200 K$ and $T_{D} = 1200 K$ , then the work done per cycle is

Discussion

38.	Figure shows a particle starting from point A, travelling upto B with a speed s, then upto point C with a speed 2s and finally upto A with a speed of 3s. Find its average speed.
Answer» Figure shows a particle starting from point A, travelling upto B with a speed $s$ , then upto point C with a speed $2 s$ and finally upto A with a speed of $3 s$ . Find its average speed.

Discussion

39.	If~y=exp{sin2x+sin4x+sin6x+.......}then dydx=
Answer» $If~y=exp {s i n^{2} x + s i n^{4} x + s i n^{6} x + . . . . . . .} t h e n \frac{d y}{d x} =$

Discussion

40.	A nucleus with mass number 220 initially at rest emits an α -particle. If the Q value of the reaction is 5.5 MeV, then the kinetic energy of the α -particle is
Answer» A nucleus with mass number 220 initially at rest emits an $α$ -particle. If the Q value of the reaction is 5.5 MeV, then the kinetic energy of the $α$ -particle is

Discussion

41.	In a Young's double slit experiment λ=500 nm, d=1 mm and D=1 m. The minimum distance from the central maximum for which the intensity is half of the maximum intensity is
Answer» In a Young's double slit experiment $λ = 500 n m, d = 1 m m and D = 1 m .$ The minimum distance from the central maximum for which the intensity is half of the maximum intensity is

Discussion

42.	Two transparent mediums of refractive indices μ1 and μ3 have a solid lens shaped transparent material of refractive index μ2 between them as shown in figures. A ray traversing these mediums is also shown in the figures. Column I, Column II and Column III represent different relationship among refractive index (μ), wavelength of light (l) and velocity of light (v) in 3 different media. Column IColumn IIColumn III(I)μ1>μ2(i)λ2>λ3(P)v2>v1(II)μ3>μ2(ii)λ1=λ3(Q)v2=v3(III)μ1>μ3(iii)λ1<λ2(R)v3<v2(IV)μ2>μ3(iv)λ2<λ3(S)v1=v3 Which of the combination is correct for figure 2?
Answer» Two transparent mediums of refractive indices $μ_{1}$ and $μ_{3}$ have a solid lens shaped transparent material of refractive index $μ_{2}$ between them as shown in figures. A ray traversing these mediums is also shown in the figures. Column I, Column II and Column III represent different relationship among refractive index $(μ)$ , wavelength of light (l) and velocity of light (v) in 3 different media. $\begin{matrix} C o l u m n I & C o l u m n I I & C o l u m n I I I (I) & μ_{1} > μ_{2} & (i) & λ_{2} > λ_{3} & (P) & v_{2} > v_{1} (I I) & μ_{3} > μ_{2} & (i i) & λ_{1} = λ_{3} & (Q) & v_{2} = v_{3} (I I I) & μ_{1} > μ_{3} & (i i i) & λ_{1} < λ_{2} & (R) & v_{3} < v_{2} (I V) & μ_{2} > μ_{3} & (i v) & λ_{2} < λ_{3} & (S) & v_{1} = v_{3} \end{matrix}$ Which of the combination is correct for figure 2?

Discussion

43.	A massless rod BD is suspended by two identical massless strings AB and CD of equal lengths. A block of mass m is suspended from point P such that BP is equal to x. If the fundamental frequency of the left wire is twice the fundamental frequency of right wire, then the value of x is
Answer» A massless rod $B D$ is suspended by two identical massless strings $A B$ and $C D$ of equal lengths. A block of mass $m$ is suspended from point $P$ such that $B P$ is equal to $x$ . If the fundamental frequency of the left wire is twice the fundamental frequency of right wire, then the value of $x$ is

Discussion

44.	The ratio of kinetic energy to the potential energy of a particle executing SHM at a distance equal to half its amplitude, the distance being measured from its equilibrium position is
Answer» The ratio of kinetic energy to the potential energy of a particle executing SHM at a distance equal to half its amplitude, the distance being measured from its equilibrium position is

Discussion

45.	The magnitude of vectors →A,→B and →C are respectively 12,5 and 13 units and →A+→B=→C, then the angle between →A and →B is
Answer» The magnitude of vectors $\to A, \to B$ and $\to C$ are respectively $12, 5$ and $13$ units and $\to A + \to B = \to C$ , then the angle between $\to A$ and $\to B$ is

Discussion

46.	A bucket full of hot water cools from 75∘C to 70∘C in time T1, from 70∘C to 65∘C in time T2 and from 65∘C to 60∘C in time T3. Then:
Answer» A bucket full of hot water cools from $75^{\circ} C$ to $70^{\circ} C$ in time $T_{1}$ , from $70^{\circ} C$ to $65^{\circ} C$ in time $T_{2}$ and from $65^{\circ} C$ to $60^{\circ} C$ in time $T_{3}$ . Then:

Discussion

47.	A spring block system is performing SHM with a time period of 4 s. If at any instant, the kinetic energy of the system is represented as KE and potential energy as KP, then what is the time period of oscillation of KE−KP?
Answer» A spring block system is performing $S H M$ with a time period of $4 s$ . If at any instant, the kinetic energy of the system is represented as $K_{E}$ and potential energy as $K_{P}$ , then what is the time period of oscillation of $K_{E} - K_{P}$ ?

Discussion

48.	A point source is producing sinusoidal transverse waves. If the displacement from the equilibrium position of a point 4 cm from source is half the amplitude of wave at t=T6 (T being time period). The wavelength of travelling wave is
Answer» A point source is producing sinusoidal transverse waves. If the displacement from the equilibrium position of a point $4 cm$ from source is half the amplitude of wave at $t = \frac{T}{6}$ ( $T$ being time period). The wavelength of travelling wave is

Discussion

49.	In the given figure, at the free end a force F is applied to keep the suspended mass of 18 kg at rest. The value of F (in N) is Take (g=10 m/s2)
Answer» In the given figure, at the free end a force $F$ is applied to keep the suspended mass of $18 k g$ at rest. The value of $F$ (in $N$ ) is Take $(g = 10 m / s^{2})$

Discussion

50.	An object of mass 5 kg is attached to the hook of a spring balance and the balance is suspended vertically from the roof of a lift. The reading on the spring balance when the lift is going up with an acceleration of 0.25 m/s2 is (g=10 m/s2)
Answer» An object of mass $5 kg$ is attached to the hook of a spring balance and the balance is suspended vertically from the roof of a lift. The reading on the spring balance when the lift is going up with an acceleration of $0.25 {m/s}^{2}$ is $(g = 10 {m/s}^{2})$

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A whistle revolves in a circle with angular velocity ω=20 rad/s using a string of length 50 cm. If the actual frequency of sound from the whistle is 385 Hz, then the minimum frequency heard by the observer far away from the centre is (velocity of sound v=340 m/s)

A uniform electric field pointing in positive x-direction exists in a region. Let A be the origin, B be the point on the x-axis at x = +1 cm and C be the point on the y-axis at y = +1 cm. Then the potentials at the points A, B and C satisfy

A block of mass 1 kg is at rest relative to a smooth wedge moving leftwards with constant acceleration a=5 m/ s2. Let N be the normal reaction between the block and the wedge. Then (g=10 m/s2)

A piece of solid weighs 120 g in air and 80 g when completely immersed in water. The relative density of solid is

A stone is projected from the ground. Its path is as shown in the figure. At which point is its speed decreasing at the fastest rate?

A particle of mass 0.2 kg (initially at rest) starts moving in one dimension under a force that delivers a constant power 0.5 W to the particle. Then the speed after 5 seconds is

A body is projected from the top of a tower of height 32 m with a velocity of 20 m/s at an angle of 37∘ above the horizontal. The time of flight of the projectile (in seconds) is

A wooden ball of density D is immersed in water of density d to a depth h below the surface of water and then released. Upto what height will the ball jump out of water( measured from surface of water) ?

How much heat must be removed by a refrigerator from 4 kg of water at 70∘C to convert it to ice cube at −10∘C ? [Take specific heat of water Cw=4200 J/kg/∘C, Latent heat of fusion of iceLf=334000 J/kg, Specific heat of ice Ci=2100 J/kg K]

When you put an object on a spring balance, you get

A parallel-plate capacitor having plate area 25 cm2 and separation 1.00 mm is connected to a batter of 6.0 V. Calculate the charge flown through the battery. How much work has been done by the battery during the process ?

define retardation

A body at rest may have

By use of a suitable filter, the green mercury emission line can be isolated. This line has a wavelength of 546.1 nm. What is the frequency? [1 Hz = 1 s-1]

A car travels the first half distance with constant velocity of 40 kmph and the remaining half with a constant velocity of 60 kmph. The average velocity of the car in kmph is

Consider the general motion of a wheel of radius 2 m which can be viewed as pure translation with the velocity →v and pure rotation about O with angular velocity 5 rad/s. Which of the following is incorrect?

Derive the kinematic equations of motion.

A body of mass m moving with a speed v suffers an inelastic collision with another body of M at rest and sticks to it, the ratio of the final kinetic energy of the system to the initial kinetic energy is

The initial pressure &amp; volume of a given mass of gas (CPCV=53) are P0 and V0. The gas can exchange heat with the surroundings. It is slowly compressed to volume V04 and then suddenly compressed to volume V08 and then again slowly compressed to V016. Find the final pressure.

A uniform disc of diameter R/2 is put over another uniform disc of diameter R of a same thickness and density.the peripheries of the 2 discs touch each other. the centre of mass of system from centre of big disc is 1)R/10 2)R/20 3)9R/10 4)11R/10

How many laws of reflection 2 or3

The velocity-time graph of a body is given in figure. The maximum acceleration in ms−2 is

A 2 cm diameter coin rests flat on the bottom of a bowl in which the water is 20 cm deep (μw=4/3). If the coin is viewed directly from above, what is its apparent diameter?

A vector −→F1 is along x-axis. If its vector product with another vector −→F2 is zero, then −→F2 could be

A constant force F=m2g/2 is applied on the block of mass m1 as shown in figure. The string and the pulley are light and the surface of the table is smooth. Find the acceleration of m1.

A galvanometer (G) is shunted such that only 111th of the main current flows through it. If G=150 Ω the shunt resistance is

A vessel contains a mixture of one mole of oxygen and two moles of nitrogen at 300 K. The ratio of the average rotational kinetic energy per O2 molecule to that per N2 molecule is

Visible light of wavelength 6000×10−8cm falls normally on a single slit and produces a diffraction pattern. It is found that the second diffraction minima is at 60o from the central maxima. If the first minimum is produced at θ1, then θ1 is close to

The position of a particle is given by →r=3t^i+√3t2^j−4^k where t is in seconds and →r is meters. Find out magnitude of velocity →v and angle made by velocity →v with X-axis at t=√3 s.

The metallic bob of a simple pendulum has the relative density ρ. The time period of this pendulum is T. If the metallic bob is immersed completely in water, then the new time period is given by

The volume charge density as a function of distance x from one face inside a cube of side 2 m, is varying as shown in the figure. Find the total flux (in S.I. units) through the cube. (If ρ0=8.85×10−12C/m3) ___

A projectile is fired at an angle of 45o with the horizontal. Elevation angle of the projectile at its highest point as seen from the point of projection is

What is the angular velocity in rad/s of a wheel making 1200 revolutions in 50 minutes ?

Six moles of an ideal gas undergo a cyclic process shown in the figure. If the temperatures are given as TA=600 K, TB=800 K, TC=2200 K and TD=1200 K, then the work done per cycle is

Figure shows a particle starting from point A, travelling upto B with a speed s, then upto point C with a speed 2s and finally upto A with a speed of 3s. Find its average speed.

If~y=exp{sin2x+sin4x+sin6x+.......}then dydx=

A nucleus with mass number 220 initially at rest emits an α -particle. If the Q value of the reaction is 5.5 MeV, then the kinetic energy of the α -particle is

In a Young's double slit experiment λ=500 nm, d=1 mm and D=1 m. The minimum distance from the central maximum for which the intensity is half of the maximum intensity is

A massless rod BD is suspended by two identical massless strings AB and CD of equal lengths. A block of mass m is suspended from point P such that BP is equal to x. If the fundamental frequency of the left wire is twice the fundamental frequency of right wire, then the value of x is

The ratio of kinetic energy to the potential energy of a particle executing SHM at a distance equal to half its amplitude, the distance being measured from its equilibrium position is

The magnitude of vectors →A,→B and →C are respectively 12,5 and 13 units and →A+→B=→C, then the angle between →A and →B is

A bucket full of hot water cools from 75∘C to 70∘C in time T1, from 70∘C to 65∘C in time T2 and from 65∘C to 60∘C in time T3. Then:

A spring block system is performing SHM with a time period of 4 s. If at any instant, the kinetic energy of the system is represented as KE and potential energy as KP, then what is the time period of oscillation of KE−KP?

A point source is producing sinusoidal transverse waves. If the displacement from the equilibrium position of a point 4 cm from source is half the amplitude of wave at t=T6 (T being time period). The wavelength of travelling wave is

In the given figure, at the free end a force F is applied to keep the suspended mass of 18 kg at rest. The value of F (in N) is Take (g=10 m/s2)

An object of mass 5 kg is attached to the hook of a spring balance and the balance is suspended vertically from the roof of a lift. The reading on the spring balance when the lift is going up with an acceleration of 0.25 m/s2 is (g=10 m/s2)

The initial pressure & volume of a given mass of gas (CPCV=53) are P0 and V0. The gas can exchange heat with the surroundings. It is slowly compressed to volume V04 and then suddenly compressed to volume V08 and then again slowly compressed to V016. Find the final pressure.