50278 + Interview Questions in Physics

1.	If an incident light ray parallel to the principal axis is incident at an angle of i then find the distance of Q from the centre of curvature C if the angle of incidence is finite. Here, R is the radius of curvature.
Answer» If an incident light ray parallel to the principal axis is incident at an angle of $i$ then find the distance of $Q$ from the centre of curvature $C$ if the angle of incidence is finite. Here, $R$ is the radius of curvature.

Discussion

2.	What will be the graph be drawn if we plot the force against the distance between the two wires placed parallelly in the magnetic field?
Answer» What will be the graph be drawn if we plot the force against the distance between the two wires placed parallelly in the magnetic field?

Discussion

3.	The path of projectile is represented by y=Px−Qx2 Column IColumn II(a)Range(p)PQ(b)Maximum height(q)P(c)Time of flight(r)P24Q(d)Tangent of angle of projection(s)√2QgP
Answer» The path of projectile is represented by $y = P x - Q x^{2}$ $\begin{matrix} Column I & Column II (a) & Range & (p) & \frac{P}{Q} (b) & Maximum height & (q) & P (c) & Time of flight & (r) & \frac{P^{2}}{4 Q} (d) & Tangent of angle of projection & (s) & \sqrt{\frac{2}{Q g}} P \end{matrix}$

Discussion

4.	a projectile is fired from the surface of the earth with a velocity of 5m/s at angle theta with the horizontal.another projectile fired from another planet with a velocity of 3m/s a the same same angle follows a trajectory of the projectile fired from the earth.the value of the acceleration due to gravity on the planet is
Answer» a projectile is fired from the surface of the earth with a velocity of 5m/s at angle theta with the horizontal.another projectile fired from another planet with a velocity of 3m/s a the same same angle follows a trajectory of the projectile fired from the earth.the value of the acceleration due to gravity on the planet is

Discussion

5.	A uniform thin rod of mass, M=1 kg and length, L=2 m is hinged by a frictionless pivot at its one end O as shown in figure. A bullet of mass, m=50 g moving horizontally with a velocity v=1500 ms−1 strikes the free end of the rod and gets embedded in it the angular velocity of the system about O just after the collision is-
Answer» A uniform thin rod of mass, $M = 1 kg$ and length, $L = 2 m$ is hinged by a frictionless pivot at its one end $O$ as shown in figure. A bullet of mass, $m = 50 g$ moving horizontally with a velocity $v = 1500 {ms}^{- 1}$ strikes the free end of the rod and gets embedded in it the angular velocity of the system about $O$ just after the collision is-

Discussion

6.	A projectile is thrown with a velocity of 10√2 m/s at an angle of 45∘ with horizontal. The interval between the moments when speed is √125 m/s is(g=10 m/s2)
Answer» A projectile is thrown with a velocity of $10 \sqrt{2} m / s$ at an angle of $45^{\circ}$ with horizontal. The interval between the moments when speed is $\sqrt{125} m / s$ is $(g = 10 m / s^{2})$

Discussion

7.	Find charge on 12 nF which is in direct contact to battery (initially all capacitors are uncharged)
Answer» Find charge on $12 n F$ which is in direct contact to battery (initially all capacitors are uncharged)

Discussion

8.	Two masses m1=5 kg and m2=10 kg connected by an inextensible string over a frictionless pulley are moving as shown in the figure. The coefficient of static friction of horizontal surface is 0.15. The minimum mass m that should be put on top of m2 to stop the motion is -
Answer» Two masses $m_{1} = 5 kg and m_{2} = 10 kg$ connected by an inextensible string over a frictionless pulley are moving as shown in the figure. The coefficient of static friction of horizontal surface is 0.15. The minimum mass $m$ that should be put on top of $m_{2}$ to stop the motion is -

Discussion

9.	Show that 3/4 / 9/9
Answer» Show that 3/4 / 9/9

Discussion

10.	Two point charges + 4q and q are at a dis†an ce r apart, where should a third point charge Q be placed so that the Q charge is in equilibrium?
Answer» Two point charges + 4q and q are at a dis†an ce r apart, where should a third point charge Q be placed so that the Q charge is in equilibrium?

Discussion

11.	We know,Force=ML/T^2,Here what is the dimension of force ,is it the sum of the power of fundamental units or the total expression mentioned in the above equation?
Answer» We know, Force=ML/T^2, Here what is the dimension of force ,is it the sum of the power of fundamental units or the total expression mentioned in the above equation?

Discussion

12.	In a uniform electric field, when we move from origin to x=1 m, the potential charges by 10 V. Which of the following can be a possible magnitude of the electric field.
Answer» In a uniform electric field, when we move from origin to $x = 1 m$ , the potential charges by $10 V$ . Which of the following can be a possible magnitude of the electric field.

Discussion

13.	A magnetic field →B=B0 ^j exists in the region a<x<2a and →B=−B0 ^j in the region 2a<x<3a, where B0 is a positive constant. A positive point charge moving with a velocity →v=v0 ^i where v0 is a positive constant, enters the magnetic field at x=a. The trajectory of the charge in this region can be like,
Answer» A magnetic field $\to B = B_{0}^j$ exists in the region $a < x < 2 a$ and $\to B = - B_{0}^j$ in the region $2 a < x < 3 a$ , where $B_{0}$ is a positive constant. A positive point charge moving with a velocity $\to v = v_{0}^i$ where $v_{0}$ is a positive constant, enters the magnetic field at $x = a$ . The trajectory of the charge in this region can be like,

Discussion

14.	Why is the equation given as y=asinωt and not as y=acosωt for an object oscillating along x-axis?
Answer» Why is the equation given as y=asinωt and not as y=acosωt for an object oscillating along x-axis?

Discussion

15.	Two billiards ball are rolling on a flat table. one has the velocity components Vx = 1m/s, Vy =3 m/s and the other one has components V'x = 2m/s and V'y= 2 m/s . If both the balls start rolling from the same point, what is the angle between their paths?
Answer» Two billiards ball are rolling on a flat table. one has the velocity components Vx = 1m/s, Vy =3 m/s and the other one has components V'x = 2m/s and V'y= 2 m/s . If both the balls start rolling from the same point, what is the angle between their paths?

Discussion

16.	The resistance between OA is given by
Answer» The resistance between OA is given by

Discussion

17.	A cubical block is floating in a liquid with one fourth of its volume immersed in the liquid. If the whole of the system accelerates upwards with acceleration g/4, the fraction of volume immersed in the liquid will be
Answer» A cubical block is floating in a liquid with one fourth of its volume immersed in the liquid. If the whole of the system accelerates upwards with acceleration $g / 4$ , the fraction of volume immersed in the liquid will be

Discussion

18.	A cylinder of mass M has length L that is √3 times its radius. What is the ratio of its moment of ineria about its own axis and that about an axis passing through its centre and perpendicular to its axis ?
Answer» A cylinder of mass M has length L that is $\sqrt{3}$ times its radius. What is the ratio of its moment of ineria about its own axis and that about an axis passing through its centre and perpendicular to its axis ?

Discussion

19.	What is quantum theory and quantum entanglement?
Answer» What is quantum theory and quantum entanglement?

Discussion

20.	In a Young’s double slit experiment the slit separation is 0.5 m from the slits. For a monochromatic light of wavelength 500 nm, the distance of 3rd maxima from 2nd minima on the other side is
Answer» In a Young’s double slit experiment the slit separation is 0.5 m from the slits. For a monochromatic light of wavelength 500 nm, the distance of $3^{r d}$ maxima from $2^{n d}$ minima on the other side is

Discussion

21.	(a) A giant refracting telescope at an observatory has an objective lens of focal length 15m. If an eyepiece of focal length 1.0cm is used, what is the angular magnification of the telescope? (b) If this telescope is used to view the moon, what is the diameter of the image of the moon formed by the objective lens? The diameter of the moon is 3.48 × 106m, and the radius of lunar orbit is 3.8 × 108m.
Answer» (a) A giant refracting telescope at an observatory has an objective lens of focal length 15m. If an eyepiece of focal length 1.0cm is used, what is the angular magnification of the telescope? (b) If this telescope is used to view the moon, what is the diameter of the image of the moon formed by the objective lens? The diameter of the moon is 3.48 × 106m, and the radius of lunar orbit is 3.8 × 108m.

Discussion

22.	A ball strikes the floor vertically downward with a speed 5 m/s and rebounds with the same speed the magnitude of change of its velocity will be?
Answer» A ball strikes the floor vertically downward with a speed 5 m/s and rebounds with the same speed the magnitude of change of its velocity will be?

Discussion

23.	A 6kg weight is attached to a spring. It is pulled down and then released. It oscillates up and down. Its KE will be a) maximum in the middle of the movement. b) maximum at the bottom c) maximum just before it is released d) cons†an t
Answer» A 6kg weight is attached to a spring. It is pulled down and then released. It oscillates up and down. Its KE will be a) maximum in the middle of the movement. b) maximum at the bottom c) maximum just before it is released d) cons†an t

Discussion

24.	As shown in figure, a loop-the-loop track of radius r=10 m. A box starts sliding from a platform at a distance h above the top of the loop and goes around the loop without falling off the track. Find the minimum value of h for successful looping. (Assume friction is negligible at all surfaces).
Answer» As shown in figure, a loop-the-loop track of radius $r = 10 m$ . A box starts sliding from a platform at a distance $h$ above the top of the loop and goes around the loop without falling off the track. Find the minimum value of $h$ for successful looping. (Assume friction is negligible at all surfaces).

Discussion

25.	A double charged lithium atom is equivalent to hydrogen whose atomic number is 3. The wavelength of required radiation for emitting electron from first to third Bohr orbit in Li++ will be (Ionisation energy of hydrogen atom is 13.6 eV)
Answer» A double charged lithium atom is equivalent to hydrogen whose atomic number is 3. The wavelength of required radiation for emitting electron from first to third Bohr orbit in $L i^{+ +}$ will be (Ionisation energy of hydrogen atom is 13.6 eV)

Discussion

26.	Write the significant number for : 083
Answer» Write the significant number for : 083

Discussion

27.	In the arrangement shown in the figure mass of the block A and body B are 2m, 8m respectively .The surface between B and floor is smooth. The body B is connected to block C by means of pulley. If the whole system is released then the minimum value of mass of the block C so that the block A remains stationary with respect to B is (Coefficients of friction between A and B is μ)
Answer» In the arrangement shown in the figure mass of the block A and body B are 2m, 8m respectively .The surface between B and floor is smooth. The body B is connected to block C by means of pulley. If the whole system is released then the minimum value of mass of the block C so that the block A remains stationary with respect to B is (Coefficients of friction between A and B is $μ$ )

27.

In the arrangement shown in the figure mass of the block A and body B are 2m, 8m respectively .The surface between B and floor is smooth. The body B is connected to block C by means of pulley. If the whole system is released then the minimum value of mass of the block C so that the block A remains stationary with respect to B is (Coefficients of friction between A and B is μ)

Answer»

In the arrangement shown in the figure mass of the block A and body B are 2m, 8m respectively .The surface between B and floor is smooth. The body B is connected to block C by means of pulley. If the whole system is released then the minimum value of mass of the block C so that the block A remains stationary with respect to B is (Coefficients of friction between A and B is $μ$ )

Discussion

28.	A body of mass 1 kg moving with a velocity of 5 m/s hits a spring on its free end. The other end of spring is fixed and it has a force constant of 400 N/m. The body comes to rest after compressing the spring by 'x' m, the value of 'x' m is
Answer» A body of mass $1 kg$ moving with a velocity of $5 m/s$ hits a spring on its free end. The other end of spring is fixed and it has a force constant of $400 N/m$ . The body comes to rest after compressing the spring by ' $x$ ' $m$ , the value of ' $x$ ' $m$ is

Discussion

29.	A travelling wave pulse is given by43x2 +48t2+24xt +2where X and y are in metre and t is in second. Thevelocity of wave is
Answer» A travelling wave pulse is given by43x2 +48t2+24xt +2where X and y are in metre and t is in second. Thevelocity of wave is

Discussion

30.	Moment of intertia of a uniform square plate of massm and side a , about an axis passing through centreof mass of the square and in the plane of the squareas shown in figure is
Answer» Moment of intertia of a uniform square plate of massm and side a , about an axis passing through centreof mass of the square and in the plane of the squareas shown in figure is

Discussion

31.	The bob of a pendulum of mass (m) at rest is given a sharp hit to impart the horizontal velocity √6gl, where l is the length of the pendulum. Find the tension in the string at highest point?
Answer» The bob of a pendulum of mass ( $m$ ) at rest is given a sharp hit to impart the horizontal velocity $\sqrt{6 g l}$ , where $l$ is the length of the pendulum. Find the tension in the string at highest point?

Discussion

32.	A particle is projected downwards from point 'A' with initial velocity 5 m/s at an angle θ=37oC with the vertical. A strong horizontal wind gives the particle a constant horizontal acceleration of 6 m/s2 in the x - direction. If the particle strikes the ground directly under its released position, the height 'h' of point A (in m) is (answer upto two decimal places). The downward acceleration is taken as g=10 m/s2 , take (sin37°=3/5, cos37°=4/5)
Answer» A particle is projected downwards from point 'A' with initial velocity $5 m / s$ at an angle $θ = 37^{o} C$ with the vertical. A strong horizontal wind gives the particle a constant horizontal acceleration of $6 m / s^{2}$ in the x - direction. If the particle strikes the ground directly under its released position, the height 'h' of point A (in $m$ ) is (answer upto two decimal places). The downward acceleration is taken as $g = 10 m / s^{2}$ , take (sin37°=3/5, cos37°=4/5)

Discussion

33.	how much force is required to stop a bus (in 10 seconds) of mass 5000kg moving with a speed of 72km/
Answer» how much force is required to stop a bus (in 10 seconds) of mass 5000kg moving with a speed of 72km/

Discussion

34.	A converging lens of focal length 20 cm and a diverging mirror of focal length 10 cm are placed 5 cm apart with their principal axes coinciding. Where should an object be placed so that its image falls on itself?
Answer» A converging lens of focal length $20 cm$ and a diverging mirror of focal length $10 cm$ are placed $5 cm$ apart with their principal axes coinciding. Where should an object be placed so that its image falls on itself?

Discussion

35.	Which of the following is a good approximation of one dimensional motion
Answer» Which of the following is a good approximation of one dimensional motion

Discussion

36.	Let the vectors a and b be such that \|a\|=3 and \|b\|=√23, then a×b is a unit vector, if the angle between a and b is a) π6 b) π4 c) π3 d) π2
Answer» Let the vectors a and b be such that $\| a \| = 3$ and $\| b \| = \frac{\sqrt{2}}{3}$ , then $a \times b$ is a unit vector, if the angle between a and b is a) $\frac{π}{6}$ b) $\frac{π}{4}$ c) $\frac{π}{3}$ d) $\frac{π}{2}$

36.

Let the vectors a and b be such that |a|=3 and |b|=√23, then a×b is a unit vector, if the angle between a and b is a) π6 b) π4 c) π3 d) π2

Answer»

Let the vectors a and b be such that $| a | = 3$ and $| b | = \frac{\sqrt{2}}{3}$ , then $a \times b$ is a unit vector, if the angle between a and b is

a) $\frac{π}{6}$

b) $\frac{π}{4}$

c) $\frac{π}{3}$

d) $\frac{π}{2}$

Discussion

37.	Four point masses, each of mass m are present at the four corners of a square of side length equal to a. Axis of rotation is passing through through one particle as shown in the figure below. The moment of inertia about the axis of rotation is
Answer» Four point masses, each of mass $m$ are present at the four corners of a square of side length equal to $a$ . Axis of rotation is passing through through one particle as shown in the figure below. The moment of inertia about the axis of rotation is

Discussion

38.	. A wooden block of mass 8 kg is tied to a string attached to the bottom of a tank. The block is completely inside the water. The tension in string is(Relative density of wood is 0.8 and g 10 m/s^{2_{}}(1) 100 N (2) 80N (3) 50 N(4) 20 N
Answer» . A wooden block of mass 8 kg is tied to a string attached to the bottom of a tank. The block is completely inside the water. The tension in string is(Relative density of wood is 0.8 and g 10 m/s^{2_{}}(1) 100 N (2) 80N (3) 50 N(4) 20 N

Discussion

39.	Explain the expression in second closed organ pipe. l=3λ4λ=4L3n8=3v4Lλ=3v0}
Answer» Explain the expression in second closed organ pipe. $l = 3 \frac{λ}{4} λ = \frac{4 L}{3} \begin{matrix} n_{8} = \frac{3 v}{4 L} λ = 3 v_{0} \end{matrix}}$

Discussion

40.	A 50 kg girl is swinging on a swing starting from rest. The magnitude of power delivered, when the rope (of negligible mass) is making an angle of 60∘ with the downward vertical velocity of 2 m/s, directed upwards is,
Answer» A $50 kg$ girl is swinging on a swing starting from rest. The magnitude of power delivered, when the rope (of negligible mass) is making an angle of $60^{\circ}$ with the downward vertical velocity of $2 m/s$ , directed upwards is,

Discussion

41.	The coefficient of restitution e for a perfectly inelastic collision is
Answer» The coefficient of restitution e for a perfectly inelastic collision is

41.

The coefficient of restitution e for a perfectly inelastic collision is

Answer»

The coefficient of restitution e for a perfectly inelastic collision is

Discussion

42.	As shown in the figure, on bringing a charge Q from point A to B and from B to C, the work done are 2 Joules and −3 Joules respectively. The work done in bringing the charge from C to A will be
Answer» As shown in the figure, on bringing a charge $Q$ from point $A$ to $B$ and from $B$ to $C$ , the work done are $2 Joules$ and $- 3 Joules$ respectively. The work done in bringing the charge from $C$ to $A$ will be

Discussion

43.	If the length of a simple pendulum at a given place is increased by 6 times, the ratio of the final to the initial time periods of the pendulum is .
Answer» If the length of a simple pendulum at a given place is increased by 6 times, the ratio of the final to the initial time periods of the pendulum is .

Discussion

44.	Two particles have equal masses of 5.0 g each and opposite charges of +4.0×10−5C and −4.0×10−5C. They are released from rest with a separation of 1.0 m between them find the speeds of the particles when the separation is reduced to 50 cm.
Answer» Two particles have equal masses of 5.0 g each and opposite charges of $+ 4.0 \times 10^{- 5} C$ and $- 4.0 \times 10^{- 5}$ C. They are released from rest with a separation of 1.0 m between them find the speeds of the particles when the separation is reduced to 50 cm.

Discussion

45.	Two equal point charges A and B are R distance apart.a third point charge placed on the perpendicular distance at a distance d from the centre will experience maximum electrostatic force when?
Answer» Two equal point charges A and B are R distance apart.a third point charge placed on the perpendicular distance at a distance d from the centre will experience maximum electrostatic force when?

Discussion

46.	A non-uniform bar of weight W is suspended at rest by two strings of negligible weight as shown in Fig.7.39. The angles made by the strings with the vertical are 36.9° and 53.1° respectively. The bar is 2 m long. Calculate the distance d of the centre of gravity of the bar from its left end.
Answer» A non-uniform bar of weight W is suspended at rest by two strings of negligible weight as shown in Fig.7.39. The angles made by the strings with the vertical are 36.9° and 53.1° respectively. The bar is 2 m long. Calculate the distance d of the centre of gravity of the bar from its left end.

Discussion

47.	A uniform rod AB of length l and mass m is free to rotate about point A. The rod is released from rest in horizontal position. Given that the moment of inertia of the rod about A is ml23. The initial angular acceleration of the rod will be
Answer» A uniform rod $A B$ of length $l$ and mass $m$ is free to rotate about point $A$ . The rod is released from rest in horizontal position. Given that the moment of inertia of the rod about $A$ is $\frac{m l^{2}}{3}$ . The initial angular acceleration of the rod will be

Discussion

48.	An object is moving in a circle of radius 100 m with a constant speed of 31.4 m/s. What is its average speed for one complete revolution
Answer» An object is moving in a circle of radius 100 m with a constant speed of 31.4 m/s. What is its average speed for one complete revolution

Discussion

49.	14.A convex lens of focal length 20 cm and a concave lens of focal length 5 cm are kept along the same axis with distance d between them. What is the value of d so that a parallel beam of light incidents on convex lens and leaves the concave lens as a parellel beam ?
Answer» 14.A convex lens of focal length 20 cm and a concave lens of focal length 5 cm are kept along the same axis with distance d between them. What is the value of d so that a parallel beam of light incidents on convex lens and leaves the concave lens as a parellel beam ?

Discussion

50.	A bullet with mass mb=400 g and velocity vb=100 m/s hits a ballistic pendulum of mass ma=9.6 kg and lodges into it.It makes pendulum swing up from equilibrium position and rises to height h as shown in figure. Determine the value of h. (Take g=10 m/s2)
Answer» A bullet with mass $m_{b} = 400 g$ and velocity $v_{b} = 100 m/s$ hits a ballistic pendulum of mass $m_{a} = 9.6 kg$ and lodges into it.It makes pendulum swing up from equilibrium position and rises to height $h$ as shown in figure. Determine the value of $h$ . (Take $g = 10 m / s^{2}$ )

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

If an incident light ray parallel to the principal axis is incident at an angle of i then find the distance of Q from the centre of curvature C if the angle of incidence is finite. Here, R is the radius of curvature.

What will be the graph be drawn if we plot the force against the distance between the two wires placed parallelly in the magnetic field?

The path of projectile is represented by y=Px−Qx2 Column IColumn II(a)Range(p)PQ(b)Maximum height(q)P(c)Time of flight(r)P24Q(d)Tangent of angle of projection(s)√2QgP

A projectile is thrown with a velocity of 10√2 m/s at an angle of 45∘ with horizontal. The interval between the moments when speed is √125 m/s is(g=10 m/s2)

Find charge on 12 nF which is in direct contact to battery (initially all capacitors are uncharged)

Two masses m1=5 kg and m2=10 kg connected by an inextensible string over a frictionless pulley are moving as shown in the figure. The coefficient of static friction of horizontal surface is 0.15. The minimum mass m that should be put on top of m2 to stop the motion is -

Show that 3/4 / 9/9

Two point charges + 4q and q are at a dis†an ce r apart, where should a third point charge Q be placed so that the Q charge is in equilibrium?

We know,Force=ML/T^2,Here what is the dimension of force ,is it the sum of the power of fundamental units or the total expression mentioned in the above equation?

In a uniform electric field, when we move from origin to x=1 m, the potential charges by 10 V. Which of the following can be a possible magnitude of the electric field.

Why is the equation given as y=asinωt and not as y=acosωt for an object oscillating along x-axis?

Two billiards ball are rolling on a flat table. one has the velocity components Vx = 1m/s, Vy =3 m/s and the other one has components V'x = 2m/s and V'y= 2 m/s . If both the balls start rolling from the same point, what is the angle between their paths?

The resistance between OA is given by

A cubical block is floating in a liquid with one fourth of its volume immersed in the liquid. If the whole of the system accelerates upwards with acceleration g/4, the fraction of volume immersed in the liquid will be

A cylinder of mass M has length L that is √3 times its radius. What is the ratio of its moment of ineria about its own axis and that about an axis passing through its centre and perpendicular to its axis ?

What is quantum theory and quantum entanglement?

In a Young’s double slit experiment the slit separation is 0.5 m from the slits. For a monochromatic light of wavelength 500 nm, the distance of 3rd maxima from 2nd minima on the other side is

A ball strikes the floor vertically downward with a speed 5 m/s and rebounds with the same speed the magnitude of change of its velocity will be?

A 6kg weight is attached to a spring. It is pulled down and then released. It oscillates up and down. Its KE will be a) maximum in the middle of the movement. b) maximum at the bottom c) maximum just before it is released d) cons†an t

As shown in figure, a loop-the-loop track of radius r=10 m. A box starts sliding from a platform at a distance h above the top of the loop and goes around the loop without falling off the track. Find the minimum value of h for successful looping. (Assume friction is negligible at all surfaces).

A double charged lithium atom is equivalent to hydrogen whose atomic number is 3. The wavelength of required radiation for emitting electron from first to third Bohr orbit in Li++ will be (Ionisation energy of hydrogen atom is 13.6 eV)

Write the significant number for : 083

A body of mass 1 kg moving with a velocity of 5 m/s hits a spring on its free end. The other end of spring is fixed and it has a force constant of 400 N/m. The body comes to rest after compressing the spring by 'x' m, the value of 'x' m is

A travelling wave pulse is given by43x2 +48t2+24xt +2where X and y are in metre and t is in second. Thevelocity of wave is

Moment of intertia of a uniform square plate of massm and side a , about an axis passing through centreof mass of the square and in the plane of the squareas shown in figure is

The bob of a pendulum of mass (m) at rest is given a sharp hit to impart the horizontal velocity √6gl, where l is the length of the pendulum. Find the tension in the string at highest point?

how much force is required to stop a bus (in 10 seconds) of mass 5000kg moving with a speed of 72km/

A converging lens of focal length 20 cm and a diverging mirror of focal length 10 cm are placed 5 cm apart with their principal axes coinciding. Where should an object be placed so that its image falls on itself?

Which of the following is a good approximation of one dimensional motion

Let the vectors a and b be such that |a|=3 and |b|=√23, then a×b is a unit vector, if the angle between a and b is a) π6 b) π4 c) π3 d) π2

Four point masses, each of mass m are present at the four corners of a square of side length equal to a. Axis of rotation is passing through through one particle as shown in the figure below. The moment of inertia about the axis of rotation is

. A wooden block of mass 8 kg is tied to a string attached to the bottom of a tank. The block is completely inside the water. The tension in string is(Relative density of wood is 0.8 and g 10 m/s^{2_{}}(1) 100 N (2) 80N (3) 50 N(4) 20 N

Explain the expression in second closed organ pipe. l=3λ4λ=4L3n8=3v4Lλ=3v0}

A 50 kg girl is swinging on a swing starting from rest. The magnitude of power delivered, when the rope (of negligible mass) is making an angle of 60∘ with the downward vertical velocity of 2 m/s, directed upwards is,

The coefficient of restitution e for a perfectly inelastic collision is

As shown in the figure, on bringing a charge Q from point A to B and from B to C, the work done are 2 Joules and −3 Joules respectively. The work done in bringing the charge from C to A will be

If the length of a simple pendulum at a given place is increased by 6 times, the ratio of the final to the initial time periods of the pendulum is .

Two particles have equal masses of 5.0 g each and opposite charges of +4.0×10−5C and −4.0×10−5C. They are released from rest with a separation of 1.0 m between them find the speeds of the particles when the separation is reduced to 50 cm.

Two equal point charges A and B are R distance apart.a third point charge placed on the perpendicular distance at a distance d from the centre will experience maximum electrostatic force when?

A non-uniform bar of weight W is suspended at rest by two strings of negligible weight as shown in Fig.7.39. The angles made by the strings with the vertical are 36.9° and 53.1° respectively. The bar is 2 m long. Calculate the distance d of the centre of gravity of the bar from its left end.

A uniform rod AB of length l and mass m is free to rotate about point A. The rod is released from rest in horizontal position. Given that the moment of inertia of the rod about A is ml23. The initial angular acceleration of the rod will be

An object is moving in a circle of radius 100 m with a constant speed of 31.4 m/s. What is its average speed for one complete revolution

14.A convex lens of focal length 20 cm and a concave lens of focal length 5 cm are kept along the same axis with distance d between them. What is the value of d so that a parallel beam of light incidents on convex lens and leaves the concave lens as a parellel beam ?

A bullet with mass mb=400 g and velocity vb=100 m/s hits a ballistic pendulum of mass ma=9.6 kg and lodges into it.It makes pendulum swing up from equilibrium position and rises to height h as shown in figure. Determine the value of h. (Take g=10 m/s2)