50278 + Interview Questions in Physics

1.	58.If temperature of ideal black body increased by 10% what will be % increase in quantity of radiation emitted from its surface
Answer» 58.If temperature of ideal black body increased by 10% what will be % increase in quantity of radiation emitted from its surface

Discussion

2.	Figure shows a DC voltage regulator circuit, with a Zener diode of breakdown voltage =6 V. If the unregulated input voltage varies between 10 V to 16 V, then what is the maximum Zener current ?
Answer» Figure shows a $DC$ voltage regulator circuit, with a Zener diode of breakdown voltage $= 6 V .$ If the unregulated input voltage varies between $10 V$ to $16 V,$ then what is the maximum Zener current ?

Discussion

3.	When a block of iron floats in mercury at 0∘C, fraction K1 of its volume is submerged, while at the temperature 60∘C, a fraction K2 is seen to be submerged. If the coefficient of volume expansion of iron is γFe and that of mercury is γHg, then the ratio of K1K2 can be expressed as
Answer» When a block of iron floats in mercury at $0^{\circ} C$ , fraction $K_{1}$ of its volume is submerged, while at the temperature $60^{\circ} C$ , a fraction $K_{2}$ is seen to be submerged. If the coefficient of volume expansion of iron is $γ_{F e}$ and that of mercury is $γ_{H g}$ , then the ratio of $\frac{K_{1}}{K_{2}}$ can be expressed as

Discussion

4.	Two sound waves having a phase difference of }60^° have path difference of 1)λ/6 2)λ/3 3)2λ 4)λ/2
Answer» Two sound waves having a phase difference of }60^° have path difference of 1)λ/6 2)λ/3 3)2λ 4)λ/2

Discussion

5.	Change the sentence to the active voice. Lucy is being courted by Mr Rutherford.
Answer» Change the sentence to the active voice. Lucy is being courted by Mr Rutherford.

5.

Change the sentence to the active voice. Lucy is being courted by Mr Rutherford.

Answer»

Change the sentence to the active voice.

Lucy is being courted by Mr Rutherford.

Discussion

6.	63. if a body losses three fourth of its initial velocity on penetrating 15 CM in a wooden block then how much it penetrates more before coming to rest
Answer» 63. if a body losses three fourth of its initial velocity on penetrating 15 CM in a wooden block then how much it penetrates more before coming to rest

Discussion

7.	A capacitor A of capaci†an ce 4 microfarad is charged to 30 V and another capacitor B of capaci†an ce 2 microfarad is charged to 15 V. Now the positive plate of A is connected to the negative plate of B and negative plate of A to the positive plate of B. Find the final charge of each capacitor and loss of electrostatic energy in the process
Answer» A capacitor A of capaci†an ce 4 microfarad is charged to 30 V and another capacitor B of capaci†an ce 2 microfarad is charged to 15 V. Now the positive plate of A is connected to the negative plate of B and negative plate of A to the positive plate of B. Find the final charge of each capacitor and loss of electrostatic energy in the process

Discussion

8.	In the arrangement shown in the figure, mass of the block A is 4 times that of block B. The height h=20 cm. At a certain instant, the block A is released and the system is set in motion. What is the maximum height (in cm) that the body B will go up? Assume enough space allowed for B and A (i.e A and B are of small size) and take g=10 m/s2
Answer» In the arrangement shown in the figure, mass of the block $A$ is $4$ times that of block $B$ . The height $h = 20 cm$ . At a certain instant, the block $A$ is released and the system is set in motion. What is the maximum height (in $cm)$ that the body $B$ will go up? Assume enough space allowed for $B$ and $A$ (i.e $A$ and $B$ are of small size) and take $g = 10 {m/s}^{2}$

Discussion

9.	When a ball is thrown vertically upwards with velocity v0, it reaches a maximum height of h. If one wishes to half the maximum height then the ball should be thrown with velocity.
Answer» When a ball is thrown vertically upwards with velocity $v_{0}$ , it reaches a maximum height of $h$ . If one wishes to half the maximum height then the ball should be thrown with velocity.

Discussion

10.	A thin flexible wire of length L is connected to two close adjacent fixed points and carries a current I in the clockwise direction, as shown in the figure. When the system is put in a uniform magnetic field of strength B going into the plane of the paper, the wire takes the shape of a circle. The tension in the wire is
Answer» A thin flexible wire of length $L$ is connected to two close adjacent fixed points and carries a current $I$ in the clockwise direction, as shown in the figure. When the system is put in a uniform magnetic field of strength $B$ going into the plane of the paper, the wire takes the shape of a circle. The tension in the wire is

Discussion

11.	54.A particle is seen at x=0 at t=0.The acceleration of the particle depends on time as a=2t+1 along x-axis. Q:-) If the particle has a velocity of 5 m/s along x-axis at origin, where it will be located at t=6sec?
Answer» 54.A particle is seen at x=0 at t=0.The acceleration of the particle depends on time as a=2t+1 along x-axis. Q:-) If the particle has a velocity of 5 m/s along x-axis at origin, where it will be located at t=6sec?

Discussion

12.	A hollow cylinder of length 3 m has inner and outer diameters are 4 mm and 8 mm respectively. The resistance of the cylinder is-[specific resistance of the material =2.2×10−8 Ωm]
Answer» A hollow cylinder of length $3 m$ has inner and outer diameters are $4 mm$ and $8 mm$ respectively. The resistance of the cylinder is- [specific resistance of the material $= 2.2 \times 10^{- 8} Ω m$ ]

Discussion

13.	The magnitudes of the gravitational force at distances r1 and r2 from the centre of a uniform sphere of radius R and mass M are F1 and F2 respectively. Then
Answer» The magnitudes of the gravitational force at distances $r_{1}$ and $r_{2}$ from the centre of a uniform sphere of radius R and mass M are $F_{1}$ and $F_{2}$ respectively. Then

Discussion

14.	A bob is hanging over a pulley inside a car through a string. The second end of the string is in the hand of a person standing in the car. The car is moving with constant acceleration a directed horizontally as shown in figure. Other end of the string is pulled with constant acceleration a vertically. The tension in the string is equal to
Answer» A bob is hanging over a pulley inside a car through a string. The second end of the string is in the hand of a person standing in the car. The car is moving with constant acceleration a directed horizontally as shown in figure. Other end of the string is pulled with constant acceleration a vertically. The tension in the string is equal to

14.

A bob is hanging over a pulley inside a car through a string. The second end of the string is in the hand of a person standing in the car. The car is moving with constant acceleration a directed horizontally as shown in figure. Other end of the string is pulled with constant acceleration a vertically. The tension in the string is equal to

Answer»

A bob is hanging over a pulley inside a car through a string. The second end of the string is in the hand of a person standing in the car. The car is moving with constant acceleration a directed horizontally as shown in figure. Other end of the string is pulled with constant acceleration a vertically. The tension in the string is equal to

Discussion

15.	The mass density of a spherical galaxy varies as Kr over a large distance r from its centre. In that region, a small star is in a circular orbit of radius R. Then the period of revolution, T depends on R as :
Answer» The mass density of a spherical galaxy varies as $\frac{K}{r}$ over a large distance $r$ from its centre. In that region, a small star is in a circular orbit of radius $R$ . Then the period of revolution, $T$ depends on $R$ as :

Discussion

16.	Two thin rods are moving perpendicular as shown in the figure. If the friction acting between them is f, then the unit vector in the direction of friction force acting on the rod which is lying along x−axis is (^i+2^j)√x. The value of x is
Answer» Two thin rods are moving perpendicular as shown in the figure. If the friction acting between them is $f$ , then the unit vector in the direction of friction force acting on the rod which is lying along $x - a x i s$ is $\frac{(^i + 2^j)}{\sqrt{x}}$ . The value of $x$ is

Discussion

17.	A body falling from rest describes distances S_1,S_{2 }and S_{} is the first, second and third seconds of its fall. Then the ratio of S_1:S_2:S_3, is(1) 1:1:1(2) 1:3:5(3) 1:2:3(4) 1:4:9
Answer» A body falling from rest describes distances S_1,S_{2 }and S_{} is the first, second and third seconds of its fall. Then the ratio of S_1:S_2:S_3, is(1) 1:1:1(2) 1:3:5(3) 1:2:3(4) 1:4:9

Discussion

18.	If a semiconductor photodiode can detect a photon with a maximum wavelength of 400 nm, then its band gap energy is: Planck's constant, h=6.63×10−34 JsSpeed of light, c=3×108 ms−1
Answer» If a semiconductor photodiode can detect a photon with a maximum wavelength of $400 nm$ , then its band gap energy is: $Planck's constant, h = 6.63 \times 10^{- 34} Js$ $Speed of light, c = 3 \times 10^{8} {ms}^{- 1}$

Discussion

19.	A rather soft, silvery metal was observed to have a specific heat of 0.225 cal K−1g−1. Thus, metal is
Answer» A rather soft, silvery metal was observed to have a specific heat of $0.225 c a l K^{- 1} g^{- 1} .$ Thus, metal is

Discussion

20.	Q,.Displacement x of a simple harmonic oscillator varies with time, according to differntial euation d^2x/dt^2 +4x =0 Then its time period will be?
Answer» Q,.Displacement x of a simple harmonic oscillator varies with time, according to differntial euation d^2x/dt^2 +4x =0 Then its time period will be?

Discussion

21.	147.Explain Combination of capacitors
Answer» 147.Explain Combination of capacitors

Discussion

22.	A jet of water is projected at an angle θ=45∘ with the horizontal from a point which is at a distance of x=15 m from a vertical wall as shown in the figure. If the speed of projection is 10√2 m/s, find out the height from ground at which the water jet strikes vertical wall. Take g=10 m/s2
Answer» A jet of water is projected at an angle $θ = 45^{\circ}$ with the horizontal from a point which is at a distance of $x = 15 m$ from a vertical wall as shown in the figure. If the speed of projection is $10 \sqrt{2} m/s$ , find out the height from ground at which the water jet strikes vertical wall. Take $g = 10 {m/s}^{2}$

Discussion

23.	Consider a frame that is made up of two thin massless rods AB and AC as shown in the figure. A vertical force →P of magnitude 100 N is applied at point A of the frame.Suppose the force →P resolved parallel to the arms AB and AC of the frame. The magnitude of the resolved component along the arm AC is x N. The value of x, to the nearest integer, is .[Given: sin (35°) = 0.573, cos (35°) = 0.819, sin (110°) = 0.939, cos (110°) = -0.342]
Answer» Consider a frame that is made up of two thin massless rods AB and AC as shown in the figure. A vertical force $\to P$ of magnitude $100 N$ is applied at point A of the frame. Suppose the force $\to P$ resolved parallel to the arms AB and AC of the frame. The magnitude of the resolved component along the arm AC is $x N$ . The value of $x$ , to the nearest integer, is . [Given: sin (35°) = 0.573, cos (35°) = 0.819, sin (110°) = 0.939, cos (110°) = -0.342]

Discussion

24.	An aeroplane is in a level flight at 144 km/hr at an altitude of 1000 m. How far from target should a bomb be released from it to hit the target
Answer» An aeroplane is in a level flight at 144 km/hr at an altitude of 1000 m. How far from target should a bomb be released from it to hit the target

Discussion

25.	11.A ball of mass m is released from track A , where h=3R then find out the normal force exerted by track B on the ball ? A) mg/2 B) 3/2 mg. C) mg D) 2mg
Answer» 11.A ball of mass m is released from track A , where h=3R then find out the normal force exerted by track B on the ball ? A) mg/2 B) 3/2 mg. C) mg D) 2mg

Discussion

26.	Two strings (fixed at both ends) P and Q of equal length, made of same material and vibrating in same mode produces beats of frequency 5 Hz. Initial string Q is vibrating at a frequency 460 Hz. If the tension in string P increases, the beat frequency increases to 7 Hz. The initial frequency of vibration for string P is :
Answer» Two strings (fixed at both ends) $P$ and $Q$ of equal length, made of same material and vibrating in same mode produces beats of frequency $5 Hz$ . Initial string $Q$ is vibrating at a frequency $460 Hz$ . If the tension in string $P$ increases, the beat frequency increases to $7 Hz$ . The initial frequency of vibration for string $P$ is :

Discussion

27.	The Henry's law constant for the solubility of N2 gas in water at 298 K is 1.0×105 atm. The mole fraction of N2 in air is 0.8. The number of moles of N2 dissolved in 10 moles of water at 298 K and 5 atm is x×10−4. Find the value of x.
Answer» The Henry's law constant for the solubility of $N_{2}$ gas in water at $298 K$ is $1.0 \times 10^{5} atm$ . The mole fraction of $N_{2}$ in air is $0.8$ . The number of moles of $N_{2}$ dissolved in $10$ moles of water at $298 K$ and $5 atm$ is $x \times 10^{- 4}$ . Find the value of $x$ .

Discussion

28.	A point mass oscillates along the x−axis according to the law x=x0cos(ωt−π/4). If the acceleration of the particle is written as a=Acos(ωt+δ), then
Answer» A point mass oscillates along the $x -$ axis according to the law $x = x_{0} cos (ω t - π / 4)$ . If the acceleration of the particle is written as $a = A cos (ω t + δ)$ , then

Discussion

29.	Potential in the x–y plane is given as V = –10 (x^2+ y) volts. The electric field at the point (1 m, 1 m) will be Options: (a)10V/m (b)10\sqrt3V/m (c)20V/m
Answer» Potential in the x–y plane is given as V = –10 (x^2+ y) volts. The electric field at the point (1 m, 1 m) will be Options: (a)10V/m (b)10\sqrt3V/m (c)20V/m

Discussion

30.	Show that if the room temperature changes by a small amount from T to T+ΔT, the fundamental frequency of an organ pipe changes from v to v+Δv, where Δvv=12ΔTT.
Answer» Show that if the room temperature changes by a small amount from T to $T + Δ T$ , the fundamental frequency of an organ pipe changes from v to $v + Δ v$ , where $\frac{Δ v}{v} = \frac{1}{2} \frac{Δ T}{T} .$

Discussion

31.	Charge in the form of a plane sheet with density σ=40μ C/m2 is located at z=–0.5 m. A uniform line of charge of density λ=−6μ C/m lies along the y− axis. Net flux that crosses the surface of cube 2 m as an edge, centered at the origin as shown, is K10−6ε0NCm2. Then value of K is
Answer» Charge in the form of a plane sheet with density $σ = 40 μ {C/m}^{2}$ is located at $z = - 0.5 m$ . A uniform line of charge of density $λ = - 6 μ C/m$ lies along the $y -$ axis. Net flux that crosses the surface of cube $2 m$ as an edge, centered at the origin as shown, is $K \frac{10^{- 6}}{ε_{0}} \frac{N}{C} m^{2}$ . Then value of $K$ is

Discussion

32.	A body of mass 0.40 kg moving initially with a constant speed of 10 m s-1 to the north is subject to a constant force of 8.0 N directed towards the south for 30 s. Take the instant the force is applied to be t = 0, the position of the body at that time to be x = 0, and predict its position at t = –5 s, 25 s, 100 s.
Answer» A body of mass 0.40 kg moving initially with a constant speed of 10 m s-1 to the north is subject to a constant force of 8.0 N directed towards the south for 30 s. Take the instant the force is applied to be t = 0, the position of the body at that time to be x = 0, and predict its position at t = –5 s, 25 s, 100 s.

Discussion

33.	A light ray is incident on an equilateral prism of refractive index 5/3. What should be the angle of incidence such that the ray grazes on the second surface ?
Answer» A light ray is incident on an equilateral prism of refractive index 5/3. What should be the angle of incidence such that the ray grazes on the second surface ?

Discussion

34.	Does short-sightedness (myopia) or long-sightedness (hyper -metropia) imply necessarily that the eye has partially lost its abilityof accommodation? If not, what might cause these defects of vision?
Answer» Does short-sightedness (myopia) or long-sightedness (hyper -metropia) imply necessarily that the eye has partially lost its abilityof accommodation? If not, what might cause these defects of vision?

Discussion

35.	The same progressive wave is represented by two graphs I and II. Graph I shows how the displacement y varies with the distance x along the wave at a given time. Graph II shows how y varies with time t at a given point on the wave. The ratio of measurements AB to CD, marked on the curves, represents:
Answer» The same progressive wave is represented by two graphs I and II. Graph I shows how the displacement y varies with the distance x along the wave at a given time. Graph II shows how y varies with time t at a given point on the wave. The ratio of measurements AB to CD, marked on the curves, represents:

Discussion

36.	The volume V of a monoatomic gas varies with its temperature T, as shown in the graph. The ratio of work done by the gas, to the heat absorbed by it, when it undergoes a change from state A to state B, is
Answer» The volume $V$ of a monoatomic gas varies with its temperature $T$ , as shown in the graph. The ratio of work done by the gas, to the heat absorbed by it, when it undergoes a change from state $A$ to state $B$ , is

Discussion

37.	Two waves of same frequency and intensity superimpose with each other in opposite phases, then after superposition the [AFMC 1995]
Answer» Two waves of same frequency and intensity superimpose with each other in opposite phases, then after superposition the [AFMC 1995]

37.

Two waves of same frequency and intensity superimpose with each other in opposite phases, then after superposition the [AFMC 1995]

Answer»

Two waves of same frequency and intensity superimpose with each other in opposite phases, then after superposition the

[AFMC 1995]

Discussion

38.	What is the temperature at which oxygen molecules have the same r.m.s velocity as hydrogen molecules at 27∘ C?
Answer» What is the temperature at which oxygen molecules have the same r.m.s velocity as hydrogen molecules at $27^{\circ}$ C?

Discussion

39.	Find the period of the free oscillations of the arrangement shown below, if mass M1 is pulled down a little.[Force constant of the spring is k and mass of the fixed pulley is negligible]
Answer» Find the period of the free oscillations of the arrangement shown below, if mass $M_{1}$ is pulled down a little. [Force constant of the spring is $k$ and mass of the fixed pulley is negligible]

Discussion

40.	Resolve a weight of 10N in two directions which are parallel and perpendicular to a slope inclined at 30^° to the horizontal.
Answer» Resolve a weight of 10N in two directions which are parallel and perpendicular to a slope inclined at 30^° to the horizontal.

Discussion

41.	Particle is dropped from a height of 20 m on horizontal ground. There is wind blowing due to which horizontal acceleration of the particle is 6 ms^{-2}. The horizontal displacement of the particle when it reaches the ground is : ______
Answer» Particle is dropped from a height of 20 m on horizontal ground. There is wind blowing due to which horizontal acceleration of the particle is 6 ms^{-2}. The horizontal displacement of the particle when it reaches the ground is : ______

Discussion

42.	A shell is fired from a fixed artillery gun with an initial speed u such that it hits the target on the ground at a distance R from it. If t1 and t2 are the values of the time taken by it to hit the target in two possible ways, the product t1t2 is :
Answer» A shell is fired from a fixed artillery gun with an initial speed $u$ such that it hits the target on the ground at a distance $R$ from it. If $t_{1} and t_{2}$ are the values of the time taken by it to hit the target in two possible ways, the product $t_{1} t_{2}$ is :

Discussion

43.	Does a non-polished wooden table reflect light? Give explanation for your answer.
Answer» Does a non-polished wooden table reflect light? Give explanation for your answer.

Discussion

44.	A car moves for half of the total time of travel at 80 km/h and for rest half of the time at 40 km/h. If the total distance covered is 60 km, what is the average speed of the car?
Answer» A car moves for half of the total time of travel at 80 km/h and for rest half of the time at 40 km/h. If the total distance covered is 60 km, what is the average speed of the car?

44.

A car moves for half of the total time of travel at 80 km/h and for rest half of the time at 40 km/h. If the total distance covered is 60 km, what is the average speed of the car?

Answer»

A car moves for half of the total time of travel at 80 km/h and for rest half of the time at 40 km/h.

If the total distance covered is 60 km, what is the average speed of the car?

Discussion

45.	The bob of a simple pendulum is displaced from its equilibrium position O to a position Q, which is at height h above O and the bob is then released. Assuming the mass of the bob to be m and time period of oscillations to be 2 s, the tension in the string, when the bob passes through O is
Answer» The bob of a simple pendulum is displaced from its equilibrium position $O$ to a position $Q$ , which is at height $h$ above $O$ and the bob is then released. Assuming the mass of the bob to be $m$ and time period of oscillations to be $2 s$ , the tension in the string, when the bob passes through $O$ is

Discussion

46.	Three vectors →A=^i+2^j+3^k,→B=−^i+2^j+^k and →C=3^i+^j are given. If →A+t→B is perpendicular to →C then, t is
Answer» Three vectors $\to A =^i + 2^j + 3^k, \to B = -^i + 2^j +^k$ and $\to C = 3^i +^j$ are given. If $\to A + t \to B$ is perpendicular to $\to C$ then, t is

Discussion

47.	The orbital speeds of 2 satellites having the ratio of their time period as 64:1 are: (Consider V01 and V02 are the orbital speed of satellites)
Answer» The orbital speeds of $2$ satellites having the ratio of their time period as $64 : 1$ are: (Consider $V_{01}$ and $V_{02}$ are the orbital speed of satellites)

Discussion

48.	The surface charge density of a hollow hemisphere varies with θ as σ=σ0 cosθ. The situation is shown in the figure. Find the total charge on the hemisphere.
Answer» The surface charge density of a hollow hemisphere varies with $θ$ as $σ = σ_{0} cos θ$ . The situation is shown in the figure. Find the total charge on the hemisphere.

Discussion

49.	Four persons A,B,C and D at the corners of an square of side X move at a constant speed V. Each person maintains a direction towards the person at the next corner. The time, the persons take to meet each other is
Answer» Four persons $A, B, C$ and $D$ at the corners of an square of side $X$ move at a constant speed $V$ . Each person maintains a direction towards the person at the next corner. The time, the persons take to meet each other is

Discussion

50.	Three objects A, B and C are kept in a straight line on a frictionless horizontal surface. These have masses m, 2m and m respectively. The object A moves towards B with a speed of 9 m/s and makes an elastic collision with it. Thereafter, B makes completely inelastic collision with C. All motions occur on the same straight line. Find the final speed (in m/s) of object C.
Answer» Three objects $A$ , $B$ and $C$ are kept in a straight line on a frictionless horizontal surface. These have masses $m$ , $2 m$ and $m$ respectively. The object $A$ moves towards $B$ with a speed of $9 m/s$ and makes an elastic collision with it. Thereafter, $B$ makes completely inelastic collision with $C$ . All motions occur on the same straight line. Find the final speed (in m/s) of object $C$ .

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

58.If temperature of ideal black body increased by 10% what will be % increase in quantity of radiation emitted from its surface

Figure shows a DC voltage regulator circuit, with a Zener diode of breakdown voltage =6 V. If the unregulated input voltage varies between 10 V to 16 V, then what is the maximum Zener current ?

When a block of iron floats in mercury at 0∘C, fraction K1 of its volume is submerged, while at the temperature 60∘C, a fraction K2 is seen to be submerged. If the coefficient of volume expansion of iron is γFe and that of mercury is γHg, then the ratio of K1K2 can be expressed as

Two sound waves having a phase difference of }60^° have path difference of 1)λ/6 2)λ/3 3)2λ 4)λ/2

Change the sentence to the active voice. Lucy is being courted by Mr Rutherford.

63. if a body losses three fourth of its initial velocity on penetrating 15 CM in a wooden block then how much it penetrates more before coming to rest

When a ball is thrown vertically upwards with velocity v0, it reaches a maximum height of h. If one wishes to half the maximum height then the ball should be thrown with velocity.

54.A particle is seen at x=0 at t=0.The acceleration of the particle depends on time as a=2t+1 along x-axis. Q:-) If the particle has a velocity of 5 m/s along x-axis at origin, where it will be located at t=6sec?

A hollow cylinder of length 3 m has inner and outer diameters are 4 mm and 8 mm respectively. The resistance of the cylinder is-[specific resistance of the material =2.2×10−8 Ωm]

The magnitudes of the gravitational force at distances r1 and r2 from the centre of a uniform sphere of radius R and mass M are F1 and F2 respectively. Then

The mass density of a spherical galaxy varies as Kr over a large distance r from its centre. In that region, a small star is in a circular orbit of radius R. Then the period of revolution, T depends on R as :

Two thin rods are moving perpendicular as shown in the figure. If the friction acting between them is f, then the unit vector in the direction of friction force acting on the rod which is lying along x−axis is (^i+2^j)√x. The value of x is

A body falling from rest describes distances S_1,S_{2 }and S_{} is the first, second and third seconds of its fall. Then the ratio of S_1:S_2:S_3, is(1) 1:1:1(2) 1:3:5(3) 1:2:3(4) 1:4:9

If a semiconductor photodiode can detect a photon with a maximum wavelength of 400 nm, then its band gap energy is: Planck's constant, h=6.63×10−34 JsSpeed of light, c=3×108 ms−1

A rather soft, silvery metal was observed to have a specific heat of 0.225 cal K−1g−1. Thus, metal is

Q,.Displacement x of a simple harmonic oscillator varies with time, according to differntial euation d^2x/dt^2 +4x =0 Then its time period will be?

147.Explain Combination of capacitors

A jet of water is projected at an angle θ=45∘ with the horizontal from a point which is at a distance of x=15 m from a vertical wall as shown in the figure. If the speed of projection is 10√2 m/s, find out the height from ground at which the water jet strikes vertical wall. Take g=10 m/s2

An aeroplane is in a level flight at 144 km/hr at an altitude of 1000 m. How far from target should a bomb be released from it to hit the target

11.A ball of mass m is released from track A , where h=3R then find out the normal force exerted by track B on the ball ? A) mg/2 B) 3/2 mg. C) mg D) 2mg

The Henry's law constant for the solubility of N2 gas in water at 298 K is 1.0×105 atm. The mole fraction of N2 in air is 0.8. The number of moles of N2 dissolved in 10 moles of water at 298 K and 5 atm is x×10−4. Find the value of x.

A point mass oscillates along the x−axis according to the law x=x0cos(ωt−π/4). If the acceleration of the particle is written as a=Acos(ωt+δ), then

Potential in the x–y plane is given as V = –10 (x^2+ y) volts. The electric field at the point (1 m, 1 m) will be Options: (a)10V/m (b)10\sqrt3V/m (c)20V/m

Show that if the room temperature changes by a small amount from T to T+ΔT, the fundamental frequency of an organ pipe changes from v to v+Δv, where Δvv=12ΔTT.

Charge in the form of a plane sheet with density σ=40μ C/m2 is located at z=–0.5 m. A uniform line of charge of density λ=−6μ C/m lies along the y− axis. Net flux that crosses the surface of cube 2 m as an edge, centered at the origin as shown, is K10−6ε0NCm2. Then value of K is

A light ray is incident on an equilateral prism of refractive index 5/3. What should be the angle of incidence such that the ray grazes on the second surface ?

Does short-sightedness (myopia) or long-sightedness (hyper -metropia) imply necessarily that the eye has partially lost its abilityof accommodation? If not, what might cause these defects of vision?

The volume V of a monoatomic gas varies with its temperature T, as shown in the graph. The ratio of work done by the gas, to the heat absorbed by it, when it undergoes a change from state A to state B, is

Two waves of same frequency and intensity superimpose with each other in opposite phases, then after superposition the [AFMC 1995]

What is the temperature at which oxygen molecules have the same r.m.s velocity as hydrogen molecules at 27∘ C?

Find the period of the free oscillations of the arrangement shown below, if mass M1 is pulled down a little.[Force constant of the spring is k and mass of the fixed pulley is negligible]

Resolve a weight of 10N in two directions which are parallel and perpendicular to a slope inclined at 30^° to the horizontal.

Particle is dropped from a height of 20 m on horizontal ground. There is wind blowing due to which horizontal acceleration of the particle is 6 ms^{-2}. The horizontal displacement of the particle when it reaches the ground is : ______

A shell is fired from a fixed artillery gun with an initial speed u such that it hits the target on the ground at a distance R from it. If t1 and t2 are the values of the time taken by it to hit the target in two possible ways, the product t1t2 is :

Does a non-polished wooden table reflect light? Give explanation for your answer.

A car moves for half of the total time of travel at 80 km/h and for rest half of the time at 40 km/h. If the total distance covered is 60 km, what is the average speed of the car?

The bob of a simple pendulum is displaced from its equilibrium position O to a position Q, which is at height h above O and the bob is then released. Assuming the mass of the bob to be m and time period of oscillations to be 2 s, the tension in the string, when the bob passes through O is

Three vectors →A=^i+2^j+3^k,→B=−^i+2^j+^k and →C=3^i+^j are given. If →A+t→B is perpendicular to →C then, t is

The orbital speeds of 2 satellites having the ratio of their time period as 64:1 are: (Consider V01 and V02 are the orbital speed of satellites)

The surface charge density of a hollow hemisphere varies with θ as σ=σ0 cosθ. The situation is shown in the figure. Find the total charge on the hemisphere.

Four persons A,B,C and D at the corners of an square of side X move at a constant speed V. Each person maintains a direction towards the person at the next corner. The time, the persons take to meet each other is