50278 + Interview Questions in Physics

1.	A sample of 0.1 g of water at 100°C and normal pressure (1.013×105 Nm–2) requires 54 cal of heat energy to convert to steam at 100°C. If the volume of the steam produced is 167.1 cc, the change in internal energy of the sample is
Answer» A sample of $0.1 g$ of water at $100 ° C$ and normal pressure ( $1.013 \times 10^{5} N m^{- 2}$ ) requires $54 c a l$ of heat energy to convert to steam at $100 ° C$ . If the volume of the steam produced is $167.1 c c,$ the change in internal energy of the sample is

Discussion

2.	The equation of the line passing through the points (0,−3) and (4,3) is
Answer» The equation of the line passing through the points $(0, - 3)$ and $(4, 3)$ is

Discussion

3.	A semi-infinite wire is present at centre a of a ring of raidus R. Find the flux through the ring.
Answer» A semi-infinite wire is present at centre a of a ring of raidus R. Find the flux through the ring.

Discussion

4.	A car is moving along a circular path of radius 500 m with a speed of 30 m/s. If at some instant, its speed increases at the rate of 2 m/s2, then at that instant, the magnitude of resultant acceleration will be
Answer» A car is moving along a circular path of radius $500 m$ with a speed of $30 m / s$ . If at some instant, its speed increases at the rate of $2 m / s^{2}$ , then at that instant, the magnitude of resultant acceleration will be

Discussion

5.	Two thin discs each of mass 4.0 kg and radius 0.4 kg and radius 0.4 m are attached as shown in figure to form a rigidbody. What is the rotational inertia of this body about an axis perpendicular to the plane of disc B and passing through its center?
Answer» Two thin discs each of mass 4.0 kg and radius 0.4 kg and radius 0.4 m are attached as shown in figure to form a rigidbody. What is the rotational inertia of this body about an axis perpendicular to the plane of disc $B$ and passing through its center?

5.

Two thin discs each of mass 4.0 kg and radius 0.4 kg and radius 0.4 m are attached as shown in figure to form a rigidbody. What is the rotational inertia of this body about an axis perpendicular to the plane of disc B and passing through its center?

Answer»

Two thin discs each of mass 4.0 kg and radius 0.4 kg and radius 0.4 m are attached as shown in figure to form a rigidbody. What is the rotational inertia of this body about an axis perpendicular to the plane of disc $B$ and passing through its center?

Discussion

6.	A uniform semi-circular wire of radius 1 m andunknown mass is lying in xy plane as shown. Thecoordinate of its centre of mass are (in m).9.SEpXOJ(2) 0,(L)(3)(t)
Answer» A uniform semi-circular wire of radius 1 m andunknown mass is lying in xy plane as shown. Thecoordinate of its centre of mass are (in m).9.SEpXOJ(2) 0,(L)(3)(t)

Discussion

7.	Three point masses each of mass m are placed at the corners of an equilateral triangle of side a. The moment of inertia of system about the side AB is
Answer» Three point masses each of mass m are placed at the corners of an equilateral triangle of side a. The moment of inertia of system about the side AB is

Discussion

8.	19 Height at which magnitude of acceleration due to gravity will be equal to that at a depth R/2 (where R is radius of earth)
Answer» 19 Height at which magnitude of acceleration due to gravity will be equal to that at a depth R/2 (where R is radius of earth)

Discussion

9.	The spin only magnetic moment value (in Bohr magneton units) of [Cr(CO)6] is
Answer» The spin only magnetic moment value (in Bohr magneton units) of $[C r (C O)_{6}]$ is

Discussion

10.	a liquid is flowing in streamline manner in a pipe 1 with rate x.if the same liquid is flowing in a pipe of radius half of pipe1 with same pressure diference,the rate of flow of liquif
Answer» a liquid is flowing in streamline manner in a pipe 1 with rate x.if the same liquid is flowing in a pipe of radius half of pipe1 with same pressure diference,the rate of flow of liquif

Discussion

11.	A circular coil of radius R and N turns has negligible resistance. As shown in the schematic figure, its two ends are connected to two wires and it is hanging by those wires with its plane being vertical. The wires are connected to a capacitor with charge Q through a switch. The coil is in a horizontal uniform magnetic field Ba parallel to the plane of the coil. When the switch is closed, the capacitor gets discharged through the coil in a very short time. By the time the capacitor is discharged fully, magnitude of the angular momentum gained by the coil will be :( assume that the discharge time is so short that the coil has hardly rotated during this time )
Answer» A circular coil of radius $R$ and $N$ turns has negligible resistance. As shown in the schematic figure, its two ends are connected to two wires and it is hanging by those wires with its plane being vertical. The wires are connected to a capacitor with charge $Q$ through a switch. The coil is in a horizontal uniform magnetic field $B_{a}$ parallel to the plane of the coil. When the switch is closed, the capacitor gets discharged through the coil in a very short time. By the time the capacitor is discharged fully, magnitude of the angular momentum gained by the coil will be : ( assume that the discharge time is so short that the coil has hardly rotated during this time )

Discussion

12.	The value of coefficient of volume expansion of glycerin is 5×10−4 K−1. The fractional change in the density of glycerin for a rise of 40 K in its temperature will be
Answer» The value of coefficient of volume expansion of glycerin is $5 \times 10^{- 4} K^{- 1}$ . The fractional change in the density of glycerin for a rise of $40 K$ in its temperature will be

Discussion

13.	A sphere of mass m is given some angular velocity about a horizontal axis through its centre, and gently placed on a plank of mass m. The coefficient of friction between the two is μ. The plank rests on a smooth horizontal surface. The initial acceleration of the sphere relative to the plank will be
Answer» A sphere of mass m is given some angular velocity about a horizontal axis through its centre, and gently placed on a plank of mass m. The coefficient of friction between the two is μ. The plank rests on a smooth horizontal surface. The initial acceleration of the sphere relative to the plank will be

Discussion

14.	The kinetic energy acquired by a mass m in travelling a certain distance d, starting from rest, under the action of a force F such that the force F is directly proportional to t is
Answer» The kinetic energy acquired by a mass m in travelling a certain distance d, starting from rest, under the action of a force F such that the force F is directly proportional to t is

Discussion

15.	Consider the signal with amplitude spectrum shown, if the signal is sampled at a sampling period of 0.1 s. The peak amplitude of the spectrum of the sampled signal is _________.100
Answer» Consider the signal with amplitude spectrum shown, if the signal is sampled at a sampling period of 0.1 s. The peak amplitude of the spectrum of the sampled signal is _________. 100

Discussion

16.	An astronaut orbiting in a spaceship round the earth has a centripetal acceleration of 2.45 m/s2. The height of the spaceship from earth's surface is(R= radius of earth )
Answer» An astronaut orbiting in a spaceship round the earth has a centripetal acceleration of $2.45 {m/s}^{2}$ . The height of the spaceship from earth's surface is $(R =$ radius of earth $)$

Discussion

17.	Obtain approximately the ratio of the nuclear radii of the gold isotope 19779 Au and the silver isotope 10747 Ag .
Answer» Obtain approximately the ratio of the nuclear radii of the gold isotope 19779 Au and the silver isotope 10747 Ag .

Discussion

18.	A fighter plane flying horizontally at an altitude of 1.5 km with speed 720 km/h passes directly overhead an anti-aircraft gun. At what angle from the vertical should the gun be fired for the shell with muzzle speed 600 m s¯¹ to hit the plane ? At what minimum altitude should the pilot fly the plane to avoid being hit ? (Take g = 10 m s¯² ).
Answer» A fighter plane flying horizontally at an altitude of 1.5 km with speed 720 km/h passes directly overhead an anti-aircraft gun. At what angle from the vertical should the gun be fired for the shell with muzzle speed 600 m s¯¹ to hit the plane ? At what minimum altitude should the pilot fly the plane to avoid being hit ? (Take g = 10 m s¯² ).

Discussion

19.	Why electric field intensity due to an infinite plane sheet does not decrease with perpendicular dis†an ce
Answer» Why electric field intensity due to an infinite plane sheet does not decrease with perpendicular dis†an ce

Discussion

20.	A freight car is moving on smooth horizontal track without any external force. Rain is falling at the rate of u m/s at an angle θ with the vertical. Rain drops are collected in the car at the rate of μ kg/s. If initial mass of the car is m0 and velocity v0 then find its velocity after time it.
Answer» A freight car is moving on smooth horizontal track without any external force. Rain is falling at the rate of u m/s at an angle $θ$ with the vertical. Rain drops are collected in the car at the rate of $μ$ kg/s. If initial mass of the car is $m_{0}$ and velocity $v_{0}$ then find its velocity after time it.

Discussion

21.	Four wires of identical length, diameters and of the same material are stretched on a sonometre wire. If the ratio of their tensions is 1 : 4 : 9 : 16 then the ratio of their fundamental frequencies are [KCET 2000]
Answer» Four wires of identical length, diameters and of the same material are stretched on a sonometre wire. If the ratio of their tensions is 1 : 4 : 9 : 16 then the ratio of their fundamental frequencies are [KCET 2000]

21.

Four wires of identical length, diameters and of the same material are stretched on a sonometre wire. If the ratio of their tensions is 1 : 4 : 9 : 16 then the ratio of their fundamental frequencies are [KCET 2000]

Answer»

Four wires of identical length, diameters and of the same material are stretched on a sonometre wire. If the ratio of their tensions is 1 : 4 : 9 : 16 then the ratio of their fundamental frequencies are

[KCET 2000]

Discussion

22.	A six ohm wire is doubled on itself .calculate new resistance
Answer» A six ohm wire is doubled on itself .calculate new resistance

Discussion

23.	The remaining volume of a glass vessel is constant at all temperatures if 1x of its volume is filled with mercury. The coefficient of volume is filled with mercury. The coefficient of volume expansion of mercury is 7 times that of glass. The value of x should be
Answer» The remaining volume of a glass vessel is constant at all temperatures if $\frac{1}{x}$ of its volume is filled with mercury. The coefficient of volume is filled with mercury. The coefficient of volume expansion of mercury is 7 times that of glass. The value of $x$ should be

Discussion

24.	(a) Three resistors 1 W, 2 W, and 3 W are combined in series. Whatis the total resistance of the combination? (b) If the combination is connected to a battery of emf 12 V andnegligible internal resistance, obtain the potential drop acrosseach resistor.
Answer» (a) Three resistors 1 W, 2 W, and 3 W are combined in series. Whatis the total resistance of the combination? (b) If the combination is connected to a battery of emf 12 V andnegligible internal resistance, obtain the potential drop acrosseach resistor.

Discussion

25.	A compressed spring of spring cons†an t k releases a ball of mass m. if the height of spring is h and the spring is compressed through a dis†an ce x, the horizontal dis†an ce covered by ball to reach ground i
Answer» A compressed spring of spring cons†an t k releases a ball of mass m. if the height of spring is h and the spring is compressed through a dis†an ce x, the horizontal dis†an ce covered by ball to reach ground i

Discussion

26.	In an isothermal process system is in contact with outside heat reservior and the change occur slowly so as to facilitate to adjust temp and in adiabatic process system is isolated. Then my question is even if adiabatic system is isolated then how the temperature changes.
Answer» In an isothermal process system is in contact with outside heat reservior and the change occur slowly so as to facilitate to adjust temp and in adiabatic process system is isolated. Then my question is even if adiabatic system is isolated then how the temperature changes.

Discussion

27.	What is the condition after which on a two media interface total Internal Reflection will occur ?
Answer» What is the condition after which on a two media interface total Internal Reflection will occur ?

Discussion

28.	A body is moving down a long inclined plane of angle of inclination θ. The coefficient of friction between the body and the plane varies as μ=0.5x, where xis the distance moved down the plane. The body will have the maximum velocity when it has travelled a distance x given by
Answer» A body is moving down a long inclined plane of angle of inclination $θ$ . The coefficient of friction between the body and the plane varies as $μ = 0.5 x$ , where $x$ is the distance moved down the plane. The body will have the maximum velocity when it has travelled a distance x given by

Discussion

29.	The component of contact force normal to the surfaces in contact is called
Answer» The component of contact force normal to the surfaces in contact is called

Discussion

30.	A bob weighing 50 grams hangs vertically at the end of string 50 cm long. If 20 gram force is applied horizontally, by how much distance the Bob is pulled aside from its initial position when it reaches in equilibrium position?
Answer» A bob weighing 50 grams hangs vertically at the end of string 50 cm long. If 20 gram force is applied horizontally, by how much distance the Bob is pulled aside from its initial position when it reaches in equilibrium position?

Discussion

31.	A capacitor of capacitance 25 μF is charged to 300 V. It is then connected across a 10 mH inductor. The resistance in the circuit is negligible. Find the potential difference across capacitor at 1.2 ms after the inductor and capacitor are connected. (sin137.6∘=0.67 and cos137.6∘=−0.74)
Answer» A capacitor of capacitance $25 μ F$ is charged to $300 V$ . It is then connected across a $10 mH$ inductor. The resistance in the circuit is negligible. Find the potential difference across capacitor at $1.2 ms$ after the inductor and capacitor are connected. $(sin {137.6}^{\circ} = 0.67 and cos {137.6}^{\circ} = - 0.74)$

Discussion

32.	In an L−C oscillation circuit, maximum charge on capacitor can be Q0. If at any instant the electrical energy is 34th of the magnetic energy, then the charge on the capacitor at that instant is
Answer» In an $L - C$ oscillation circuit, maximum charge on capacitor can be $Q_{0}$ . If at any instant the electrical energy is $\frac{3}{4} t h$ of the magnetic energy, then the charge on the capacitor at that instant is

Discussion

33.	2.A balloon carrying a ball is moving vertically upward with velocity 12m/s when the balloon is at height 65m the ball is dropped with what speed ball hit the ground.
Answer» 2.A balloon carrying a ball is moving vertically upward with velocity 12m/s when the balloon is at height 65m the ball is dropped with what speed ball hit the ground.

Discussion

34.	If qf is the free charge on the capacitor plates and qb is the bound charge on the dielectric slab of dielectric constant K placed between the capacitor plates, then bound charge qb can be expressed as
Answer» If $q_{f}$ is the free charge on the capacitor plates and $q_{b}$ is the bound charge on the dielectric slab of dielectric constant $K$ placed between the capacitor plates, then bound charge $q_{b}$ can be expressed as

Discussion

35.	Triangle law of vector addition
Answer» Triangle law of vector addition

Discussion

36.	Two particles are projected simultaneously from the towers of same height as shown in the figure with velocities VA=20 m/s and VB=10 m/s respectively. They collide in air after 0.5 seconds. Find ′θ′. Answer in degrees
Answer» Two particles are projected simultaneously from the towers of same height as shown in the figure with velocities $V_{A} = 20 m/s$ and $V_{B} = 10 m/s$ respectively. They collide in air after 0.5 seconds. Find $^{'} θ^{'}$ . Answer in degrees

Discussion

37.	A motor car is fitted with a rear view of focal lenght 20 cm.A second car 2m broad and 21.6m high is 6m away from first car. Find the position of second car as seen in the mirror of the first car.
Answer» A motor car is fitted with a rear view of focal lenght 20 cm.A second car 2m broad and 21.6m high is 6m away from first car. Find the position of second car as seen in the mirror of the first car.

Discussion

38.	A rigid horizontal smooth rod `AB` of mass `0.75 kg` and length `40 cm` can rotate freely about a fixed vertical axis through its mid point `O`. Two rings each of mass `1 kg` are initially at rest at a distance of `10 cm` from `O` on either side of the rod. The rod is set in rotation with an angular velocity of `30` radian per second. Find the velocity of each ring along the length of the rod in `m/s` when they reach the ends
Answer» A rigid horizontal smooth rod `AB` of mass `0.75 kg` and length `40 cm` can rotate freely about a fixed vertical axis through its mid point `O`. Two rings each of mass `1 kg` are initially at rest at a distance of `10 cm` from `O` on either side of the rod. The rod is set in rotation with an angular velocity of `30` radian per second. Find the velocity of each ring along the length of the rod in `m/s` when they reach the ends

Discussion

39.	Keeping the magnetic field constant, if the number of turns are halved, what is the value of new current through the solenoid when a current of 2.5 A was flowing initially?
Answer» Keeping the magnetic field constant, if the number of turns are halved, what is the value of new current through the solenoid when a current of $2.5 A$ was flowing initially?

Discussion

40.	Due to magnetic field of earth, charged particles coming from outer space
Answer» Due to magnetic field of earth, charged particles coming from outer space

Discussion

41.	Use the formula υ = √ (γ P/p) to explain why the speed of sound in air (a) is independent of pressure, (b) increases with temperature, (c) increases with humidity
Answer» Use the formula υ = √ (γ P/p) to explain why the speed of sound in air (a) is independent of pressure, (b) increases with temperature, (c) increases with humidity

Discussion

42.	Capacitor in the circuit is initially uncharged. Find out current I1, I2, I3 after a long time when the switch is closed.
Answer» Capacitor in the circuit is initially uncharged. Find out current $I_{1}, I_{2}, I_{3}$ after a long time when the switch is closed.

Discussion

43.	If xy=4,x, y>0 then the least value of x2+y2 is
Answer» If xy=4,x, y>0 then the least value of x2+y2 is

Discussion

44.	Which would require a greater force – accelerating a 2 kg mass at 5 m/s2 or a 4 kg mass at 2 m/s2 ?
Answer» Which would require a greater force – accelerating a 2 kg mass at $5$ $m / s^{2}$ or a 4 kg mass at $2$ $m / s^{2}$ ?

Discussion

45.	Four particles of equal masses are moving round a circle of radius r due to their mutual gravitation attraction. Find the angular velocity.
Answer» Four particles of equal masses are moving round a circle of radius r due to their mutual gravitation attraction. Find the angular velocity.

Discussion

46.	A chain of length l and mass m lies on the surface of a smooth sphere of Radius R\:>\:l with one end tied to the top of the sphere. Find the gravitational potential energy of the chain.
Answer» A chain of length l and mass m lies on the surface of a smooth sphere of Radius R\:>\:l with one end tied to the top of the sphere. Find the gravitational potential energy of the chain.

Discussion

47.	Figure shows five capacitors connected across a 12 V power supply. What is the charge on the 2 μF capacitor ?
Answer» Figure shows five capacitors connected across a $12 V$ power supply. What is the charge on the $2 μ F$ capacitor ?

Discussion

48.	A simple pendulum has a time period T1 when on the earth's surface and T2 when taken to a height R above the earth's surface, where R is the radius of the earth. The value of T2T1 is :
Answer» A simple pendulum has a time period $T_{1}$ when on the earth's surface and $T_{2}$ when taken to a height R above the earth's surface, where R is the radius of the earth. The value of $\frac{T_{2}}{T_{1}}$ is :

Discussion

49.	Heat generated in the given circuit will be maximum when r is
Answer» Heat generated in the given circuit will be maximum when r is

Discussion

50.	State, for each of the following physical quantities, if it is a scalar or a vector : volume, mass, speed, acceleration, density, number of moles, velocity, angular frequency, displacement, angular velocity.
Answer» State, for each of the following physical quantities, if it is a scalar or a vector : volume, mass, speed, acceleration, density, number of moles, velocity, angular frequency, displacement, angular velocity.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A sample of 0.1 g of water at 100°C and normal pressure (1.013×105 Nm–2) requires 54 cal of heat energy to convert to steam at 100°C. If the volume of the steam produced is 167.1 cc, the change in internal energy of the sample is

The equation of the line passing through the points (0,−3) and (4,3) is

A semi-infinite wire is present at centre a of a ring of raidus R. Find the flux through the ring.

A car is moving along a circular path of radius 500 m with a speed of 30 m/s. If at some instant, its speed increases at the rate of 2 m/s2, then at that instant, the magnitude of resultant acceleration will be

Two thin discs each of mass 4.0 kg and radius 0.4 kg and radius 0.4 m are attached as shown in figure to form a rigidbody. What is the rotational inertia of this body about an axis perpendicular to the plane of disc B and passing through its center?

A uniform semi-circular wire of radius 1 m andunknown mass is lying in xy plane as shown. Thecoordinate of its centre of mass are (in m).9.SEpXOJ(2) 0,(L)(3)(t)

Three point masses each of mass m are placed at the corners of an equilateral triangle of side a. The moment of inertia of system about the side AB is

19 Height at which magnitude of acceleration due to gravity will be equal to that at a depth R/2 (where R is radius of earth)

The spin only magnetic moment value (in Bohr magneton units) of [Cr(CO)6] is

a liquid is flowing in streamline manner in a pipe 1 with rate x.if the same liquid is flowing in a pipe of radius half of pipe1 with same pressure diference,the rate of flow of liquif

The value of coefficient of volume expansion of glycerin is 5×10−4 K−1. The fractional change in the density of glycerin for a rise of 40 K in its temperature will be

The kinetic energy acquired by a mass m in travelling a certain distance d, starting from rest, under the action of a force F such that the force F is directly proportional to t is

Consider the signal with amplitude spectrum shown, if the signal is sampled at a sampling period of 0.1 s. The peak amplitude of the spectrum of the sampled signal is _________.100

An astronaut orbiting in a spaceship round the earth has a centripetal acceleration of 2.45 m/s2. The height of the spaceship from earth's surface is(R= radius of earth )

Obtain approximately the ratio of the nuclear radii of the gold isotope 19779 Au and the silver isotope 10747 Ag .

Why electric field intensity due to an infinite plane sheet does not decrease with perpendicular dis†an ce

A freight car is moving on smooth horizontal track without any external force. Rain is falling at the rate of u m/s at an angle θ with the vertical. Rain drops are collected in the car at the rate of μ kg/s. If initial mass of the car is m0 and velocity v0 then find its velocity after time it.

Four wires of identical length, diameters and of the same material are stretched on a sonometre wire. If the ratio of their tensions is 1 : 4 : 9 : 16 then the ratio of their fundamental frequencies are [KCET 2000]

A six ohm wire is doubled on itself .calculate new resistance

The remaining volume of a glass vessel is constant at all temperatures if 1x of its volume is filled with mercury. The coefficient of volume is filled with mercury. The coefficient of volume expansion of mercury is 7 times that of glass. The value of x should be

(a) Three resistors 1 W, 2 W, and 3 W are combined in series. Whatis the total resistance of the combination? (b) If the combination is connected to a battery of emf 12 V andnegligible internal resistance, obtain the potential drop acrosseach resistor.

A compressed spring of spring cons†an t k releases a ball of mass m. if the height of spring is h and the spring is compressed through a dis†an ce x, the horizontal dis†an ce covered by ball to reach ground i

In an isothermal process system is in contact with outside heat reservior and the change occur slowly so as to facilitate to adjust temp and in adiabatic process system is isolated. Then my question is even if adiabatic system is isolated then how the temperature changes.

What is the condition after which on a two media interface total Internal Reflection will occur ?

A body is moving down a long inclined plane of angle of inclination θ. The coefficient of friction between the body and the plane varies as μ=0.5x, where xis the distance moved down the plane. The body will have the maximum velocity when it has travelled a distance x given by

The component of contact force normal to the surfaces in contact is called

A bob weighing 50 grams hangs vertically at the end of string 50 cm long. If 20 gram force is applied horizontally, by how much distance the Bob is pulled aside from its initial position when it reaches in equilibrium position?

A capacitor of capacitance 25 μF is charged to 300 V. It is then connected across a 10 mH inductor. The resistance in the circuit is negligible. Find the potential difference across capacitor at 1.2 ms after the inductor and capacitor are connected. (sin137.6∘=0.67 and cos137.6∘=−0.74)

In an L−C oscillation circuit, maximum charge on capacitor can be Q0. If at any instant the electrical energy is 34th of the magnetic energy, then the charge on the capacitor at that instant is

2.A balloon carrying a ball is moving vertically upward with velocity 12m/s when the balloon is at height 65m the ball is dropped with what speed ball hit the ground.

If qf is the free charge on the capacitor plates and qb is the bound charge on the dielectric slab of dielectric constant K placed between the capacitor plates, then bound charge qb can be expressed as

Triangle law of vector addition

Two particles are projected simultaneously from the towers of same height as shown in the figure with velocities VA=20 m/s and VB=10 m/s respectively. They collide in air after 0.5 seconds. Find ′θ′. Answer in degrees

A motor car is fitted with a rear view of focal lenght 20 cm.A second car 2m broad and 21.6m high is 6m away from first car. Find the position of second car as seen in the mirror of the first car.

Keeping the magnetic field constant, if the number of turns are halved, what is the value of new current through the solenoid when a current of 2.5 A was flowing initially?

Due to magnetic field of earth, charged particles coming from outer space

Use the formula υ = √ (γ P/p) to explain why the speed of sound in air (a) is independent of pressure, (b) increases with temperature, (c) increases with humidity

Capacitor in the circuit is initially uncharged. Find out current I1, I2, I3 after a long time when the switch is closed.

If xy=4,x, y>0 then the least value of x2+y2 is

Which would require a greater force – accelerating a 2 kg mass at 5 m/s2 or a 4 kg mass at 2 m/s2 ?

Four particles of equal masses are moving round a circle of radius r due to their mutual gravitation attraction. Find the angular velocity.

A chain of length l and mass m lies on the surface of a smooth sphere of Radius R\:>\:l with one end tied to the top of the sphere. Find the gravitational potential energy of the chain.

Figure shows five capacitors connected across a 12 V power supply. What is the charge on the 2 μF capacitor ?

A simple pendulum has a time period T1 when on the earth's surface and T2 when taken to a height R above the earth's surface, where R is the radius of the earth. The value of T2T1 is :

Heat generated in the given circuit will be maximum when r is

State, for each of the following physical quantities, if it is a scalar or a vector : volume, mass, speed, acceleration, density, number of moles, velocity, angular frequency, displacement, angular velocity.