50278 + Interview Questions in Physics

1.	A turn of radius 20 m is banked for the vehicles going at a speed of 36 km/h. If the coefficient of static friction between the road and the tyre is 0.4, what are the possible speeds of a vehicle so that it neither slips down nor skids up ?
Answer» A turn of radius 20 m is banked for the vehicles going at a speed of 36 km/h. If the coefficient of static friction between the road and the tyre is 0.4, what are the possible speeds of a vehicle so that it neither slips down nor skids up ?

Discussion

2.	A pendulum bob of mass m is attached to the ceiling of a cart which is accelerating with a0 as shown below. Find the angle made by the bob with the vertical.
Answer» A pendulum bob of mass m is attached to the ceiling of a cart which is accelerating with $a_{0}$ as shown below. Find the angle made by the bob with the vertical.

Discussion

3.	The dimension J/m2 can correspond to?
Answer» The dimension J/m² can correspond to?

Discussion

4.	A bullet is fired at an angle 60° with the vertical hits the levelled ground at a distance of 200m. Find the distance at which the bullet will hit the ground when fired at an angle of 30° .
Answer» A bullet is fired at an angle 60° with the vertical hits the levelled ground at a distance of 200m. Find the distance at which the bullet will hit the ground when fired at an angle of 30° .

Discussion

5.	Will there there be any interaction between an electric field and a neutral body?
Answer» Will there there be any interaction between an electric field and a neutral body?

Discussion

6.	A rectangular lamina in the x−y plane is shown below: Density of this lamina is constant along x axis and varies along y axis. If the variation in density is given as ρ(y)=16ρ0y2, then the coordinates of COM will be
Answer» A rectangular lamina in the $x - y$ plane is shown below: Density of this lamina is constant along $x$ axis and varies along $y$ axis. If the variation in density is given as $ρ (y) = 16 ρ_{0} y^{2}$ , then the coordinates of $C O M$ will be

Discussion

7.	The potential energy for a force field ¯F is given by ∪(x,y) = cos(x+y). The force acting on a particle at position given by coordinates (0, π/4) is
Answer» The potential energy for a force field $¯ F$ is given by $\cup$ (x,y) = cos(x+y). The force acting on a particle at position given by coordinates (0, $π$ /4) is

Discussion

8.	A spherical body radiates 300 W power at 650 K. If the radius were halved and temperature doubled, then find the power radiated.
Answer» A spherical body radiates $300 W$ power at $650 K$ . If the radius were halved and temperature doubled, then find the power radiated.

Discussion

9.	If external forces acting on a system have zero resultant, the centre of mass a. may move b. may accelerate c. must not move d. must not accelerate
Answer» If external forces acting on a system have zero resultant, the centre of mass a. may move b. may accelerate c. must not move d. must not accelerate

9.

If external forces acting on a system have zero resultant, the centre of mass a. may move b. may accelerate c. must not move d. must not accelerate

Answer»

If external forces acting on a system have zero resultant, the centre of mass

a. may move b. may accelerate

c. must not move d. must not accelerate

Discussion

10.	What is the peak voltage across capacitor at resonance frequency in the given circuit ?
Answer» What is the peak voltage across capacitor at resonance frequency in the given circuit ?

Discussion

11.	What is exited state of an element ? What is ground state of an element ?
Answer» What is exited state of an element ? What is ground state of an element ?

11.

What is exited state of an element ? What is ground state of an element ?

Answer»

What is exited state of an element ?

What is ground state of an element ?

Discussion

12.	A monkey staBeing on the ground wants to climb to the top of a vertical pole of 15m.he climbs 5m in 1s and slips downward 3m in next second. He keeps climbing up in this manner. Find the time taken by the monkey to climb to the top of the pole.
Answer» A monkey staBeing on the ground wants to climb to the top of a vertical pole of 15m.he climbs 5m in 1s and slips downward 3m in next second. He keeps climbing up in this manner. Find the time taken by the monkey to climb to the top of the pole.

Discussion

13.	Consider a curved surface between two different media with refractive indices n1 = 1 and n2 = 2. The relation between radius of curvature, image distance and object distance is given by
Answer» Consider a curved surface between two different media with refractive indices n₁ = 1 and n₂ = 2. The relation between radius of curvature, image distance and object distance is given by

Discussion

14.	The number of photons emitted by a bulb or 1.515x10^20 per second.If wavelength of photon is 5000A,what is the power of bulb?
Answer» The number of photons emitted by a bulb or 1.515x10^20 per second.If wavelength of photon is 5000A,what is the power of bulb?

Discussion

15.	The curie point of cobalt is 1100°c- what is meant by this?
Answer» The curie point of cobalt is 1100°c- what is meant by this?

Discussion

16.	Statements: Some bolts are not cups. All dusters are balls. All bolts are balls. Conclusions: I.All cups are bolts. II.Some dusters are bolts is a possibility.
Answer» Statements: Some bolts are not cups. All dusters are balls. All bolts are balls. Conclusions: I.All cups are bolts. II.Some dusters are bolts is a possibility.

16.

Statements: Some bolts are not cups. All dusters are balls. All bolts are balls. Conclusions: I.All cups are bolts. II.Some dusters are bolts is a possibility.

Answer»

Statements:

Some bolts are not cups.

All dusters are balls.

All bolts are balls.

Conclusions:

I.All cups are bolts.

II.Some dusters are bolts is a possibility.

Discussion

17.	(243)n5×32n+19n×3n−1=?
Answer» $\frac{{(243)}^{\frac{n}{5}} \times 3^{2 n + 1}}{9^{n} \times 3^{n - 1}} = ?$

Discussion

18.	One end of a long string of linear mass density 8.0×10−3 kg m−1 is connected to an electrically driven tuning fork of frequency 256 Hz. The other end passes over a pulley and is tied to a pan containing a mass of 90 kg. The pulley end absorbs all the incoming energy so that reflected waves at this end have negligible amplitude. At t = 0, the left end (fork end) of the string x = 0 has zero transverse displacement (y = 0) and is moving along positive y-direction. The amplitude of the wave is 5.0 cm. Write down the transverse displacement y as function of x and t that describes the wave on the string.
Answer» One end of a long string of linear mass density $8.0 \times 10^{- 3}$ kg $m^{- 1}$ is connected to an electrically driven tuning fork of frequency 256 Hz. The other end passes over a pulley and is tied to a pan containing a mass of 90 kg. The pulley end absorbs all the incoming energy so that reflected waves at this end have negligible amplitude. At t = 0, the left end (fork end) of the string x = 0 has zero transverse displacement (y = 0) and is moving along positive y-direction. The amplitude of the wave is 5.0 cm. Write down the transverse displacement y as function of x and t that describes the wave on the string.

Discussion

19.	There are two particles- an α- particle and a proton. Both are accelerated
Answer» There are two particles- an α- particle and a proton. Both are accelerated

Discussion

20.	Four metal plates numbered 1, 2, 3 and 4 are arranged as shown in Fig. The area of each plate is A and the separation between the plates is d. The capacitance of the arrangement is
Answer» Four metal plates numbered 1, 2, 3 and 4 are arranged as shown in Fig. The area of each plate is A and the separation between the plates is d. The capacitance of the arrangement is

Discussion

21.	In a hydroelectric power station, the height of the dam is 10 m. How many kg of water must fall per second on the blades of a turbine in order to generate 1 MW of electrical power? Take g=10 ms−2.
Answer» In a hydroelectric power station, the height of the dam is 10 m. How many kg of water must fall per second on the blades of a turbine in order to generate 1 MW of electrical power? Take $g = 10 m s^{- 2}$ .

Discussion

22.	An electron starting from rest has a velocity that increases linearly with time as v=k t, where k=2ms−2. The distance travelled in the first 3 seconds will be
Answer» An electron starting from rest has a velocity that increases linearly with time as $v = k t$ , where $k = 2 m s^{- 2}$ . The distance travelled in the first 3 seconds will be

22.

An electron starting from rest has a velocity that increases linearly with time as v=k t, where k=2ms−2. The distance travelled in the first 3 seconds will be

Answer»

An electron starting from rest has a velocity that increases linearly with time as $v = k t$ , where $k = 2 m s^{- 2}$ . The distance travelled in the first 3 seconds will be

Discussion

23.	A wire of length 2L, is made by joining two wires A and B of the same length, but different radii r and 2r and made of the same material. It is vibrating at a frequency such that the joint of the two wires forms a node. If the number of antinodes in wire A is p and that in B is q then the ratio p:q is
Answer» A wire of length $2 L$ , is made by joining two wires $A$ and $B$ of the same length, but different radii $r$ and $2 r$ and made of the same material. It is vibrating at a frequency such that the joint of the two wires forms a node. If the number of antinodes in wire $A$ is $p$ and that in $B$ is $q$ then the ratio $p : q$ is

Discussion

24.	A force →F=5^i+6^j−4^k acting on a body, produces a displacement →s=6→i+5→k. Work done by the force is
Answer» A force $\to F = 5^i + 6^j - 4^k$ acting on a body, produces a displacement $\to s = 6 \to i + 5 \to k$ . Work done by the force is

24.

A force →F=5^i+6^j−4^k acting on a body, produces a displacement →s=6→i+5→k. Work done by the force is

Answer»

A force $\to F = 5^i + 6^j - 4^k$ acting on a body, produces a displacement $\to s = 6 \to i + 5 \to k$ . Work done by the force is

Discussion

25.	A projectile can have the same range R for two angles of projection. If t1 and t2 are the times of flight in the two cases, then
Answer» A projectile can have the same range R for two angles of projection. If $t_{1} a n d t_{2}$ are the times of flight in the two cases, then

Discussion

26.	A small box of mass m is placed on the outer surface of a smooth fixed sphere of radius R at a point where the radius makes an angle ϕ with the vertical. The box is released from this position. Find the distance travelled by the box before it leaves contact with the sphere.
Answer» A small box of mass $m$ is placed on the outer surface of a smooth fixed sphere of radius $R$ at a point where the radius makes an angle $ϕ$ with the vertical. The box is released from this position. Find the distance travelled by the box before it leaves contact with the sphere.

Discussion

27.	A block of mass 1 kg lies on a horizontal surface in a truck. The coefficient of static friction between the block and the surface is 0.6. If the acceleration of the truck is 5 ms-2, the frictional force acting on the block is
Answer» A block of mass 1 kg lies on a horizontal surface in a truck. The coefficient of static friction between the block and the surface is 0.6. If the acceleration of the truck is 5 ms^-2, the frictional force acting on the block is

Discussion

28.	In Young's double slit experiment using two identical slits, the intensity of the maximum at the centre of the screen is I. What will be the intensity at the centre of the screen if one of the slits is closed?
Answer» In Young's double slit experiment using two identical slits, the intensity of the maximum at the centre of the screen is I. What will be the intensity at the centre of the screen if one of the slits is closed?

Discussion

29.	There are two point masses each of mass m are at the ends of a rod of mass m. The rod is released. What will be the angular speed when it becomes vertical?
Answer» There are two point masses each of mass m are at the ends of a rod of mass m. The rod is released. What will be the angular speed when it becomes vertical?

29.

There are two point masses each of mass m are at the ends of a rod of mass m. The rod is released. What will be the angular speed when it becomes vertical?

Answer»

There are two point masses each of mass m are at the ends of a rod of mass m. The rod is released. What will be the angular speed when it becomes vertical?

Discussion

30.	Two blocks A and B of masses 3 m and m respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively
Answer» Two blocks A and B of masses $3 m$ and $m$ respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively

Discussion

31.	If the unit of force and length each be increased by four times, then the unit of energy is increased by
Answer» If the unit of force and length each be increased by four times, then the unit of energy is increased by

31.

If the unit of force and length each be increased by four times, then the unit of energy is increased by

Answer»

If the unit of force and length each be increased by four times, then the unit of energy is increased by

Discussion

32.	The ratio of intensities between two coherent sound sources is 9:1. The difference of loudness in decibels (dB) between maximum and minimum intensities when they interfere in space is
Answer» The ratio of intensities between two coherent sound sources is $9 : 1$ . The difference of loudness in decibels $(dB)$ between maximum and minimum intensities when they interfere in space is

Discussion

33.	Newton's second law gives the measure of
Answer» Newton's second law gives the measure of

Discussion

34.	Two coils A and B have inductances 1.0 H and 2.0 H respectively. The resistance of each coil is 10Ω Each coil is connected to an ideal battery of emf 2.0 V at t = 0. Let iA and iB be the currents in the two cirucit at time t. Find te ration iAIB at (a) t = 100 ms, (b) T = 200 ms and (c) t = 1 s.
Answer» Two coils A and B have inductances 1.0 H and 2.0 H respectively. The resistance of each coil is $10 Ω$ Each coil is connected to an ideal battery of emf 2.0 V at t = 0. Let $i_{A}$ and $i_{B}$ be the currents in the two cirucit at time t. Find te ration $\frac{i_{A}}{I_{B}}$ at (a) t = 100 ms, (b) T = 200 ms and (c) t = 1 s.

Discussion

35.	An aeroplane is flying at a constant horizontal velocity of 600 km/hr at an elevation of 6 km towards a point directly above the target on the earth’s surface. At an appropriate time, the pilot releases a ball so that it strikes the target at the earth. The ball will appear to be falling
Answer» An aeroplane is flying at a constant horizontal velocity of 600 km/hr at an elevation of 6 km towards a point directly above the target on the earth’s surface. At an appropriate time, the pilot releases a ball so that it strikes the target at the earth. The ball will appear to be falling

Discussion

36.	A projectile is projected with initial velocity (6^i+8^j)m/sec. If g=10 ms−2, then horizontal range is
Answer» A projectile is projected with initial velocity $(6^i + 8^j) m / s e c . I f g = 10 m s^{- 2}$ , then horizontal range is

Discussion

37.	A vessel of volume V0 contains an ideal gas at pressure p0 and temperature T. Gas is continuously pumped out of this vessel at a constant volume -rate dV/dt = r keeping the temperature constant. The pressure of the gas being taken out equals the pressure inside the vessel. Find (a) the pressure of the gas as a function of time, (b) the time taken before half the original gas is pumped out.
Answer» A vessel of volume $V_{0}$ contains an ideal gas at pressure $p_{0}$ and temperature T. Gas is continuously pumped out of this vessel at a constant volume -rate dV/dt = r keeping the temperature constant. The pressure of the gas being taken out equals the pressure inside the vessel. Find (a) the pressure of the gas as a function of time, (b) the time taken before half the original gas is pumped out.

Discussion

38.	A block hangs from a string wrapped on a disc of radius 20 cm, free to rotate about its axis, which is fixed in a horizontal position. If the angular speed of the disc is 10 rad/s at some instant, with what speed is the block going down at that instant?
Answer» A block hangs from a string wrapped on a disc of radius 20 cm, free to rotate about its axis, which is fixed in a horizontal position. If the angular speed of the disc is 10 rad/s at some instant, with what speed is the block going down at that instant?

Discussion

39.	A parallel-plate capacitor has plate area 40 cm2, and separation between the plates 0.10 mm is connected to a battery of emf 2.0 V through a 16 Ω resistor. Find the electric field in the capacitor 10 ns after the connections are made.
Answer» A parallel-plate capacitor has plate area 40 $c m^{2}$ , and separation between the plates 0.10 mm is connected to a battery of emf 2.0 V through a 16 $Ω$ resistor. Find the electric field in the capacitor 10 ns after the connections are made.

Discussion

40.	Equal masses of three liquids A, B and C have temperatures 10∘C, 25∘C and 40∘C respectively. If A and B are mixed, the mixture has a temperature of 15°C. If B and C are mixed the mixture has a temperature of 30∘C. If A and C are mixed, the mixture will have a temperature of
Answer» Equal masses of three liquids A, B and C have temperatures $10^{\circ} C$ , $25^{\circ} C$ and $40^{\circ} C$ respectively. If A and B are mixed, the mixture has a temperature of 15°C. If B and C are mixed the mixture has a temperature of $30^{\circ} C$ . If A and C are mixed, the mixture will have a temperature of

Discussion

41.	Two metallic slabs of same area of cross section and length having thermal conductivities 300 W/m∘C and 200 W/m∘C respectively are connected in series combination. Find the equivalent thermal conductivity (in W/m∘C)
Answer» Two metallic slabs of same area of cross section and length having thermal conductivities $300 {W/m}^{\circ} C$ and $200 {W/m}^{\circ} C$ respectively are connected in series combination. Find the equivalent thermal conductivity (in ${W/m}^{\circ} C$ )

Discussion

42.	Define non-uniform circular motion.
Answer» Define non-uniform circular motion.

Discussion

43.	Locate the COM of a uniform hemisherical solid with respect to 0 as shown in figure. (Radius = r)
Answer» Locate the COM of a uniform hemisherical solid with respect to 0 as shown in figure. (Radius = r)

43.

Locate the COM of a uniform hemisherical solid with respect to 0 as shown in figure. (Radius = r)

Answer»

Locate the COM of a uniform hemisherical solid with respect to 0 as shown in figure. (Radius = r)

Discussion

44.	Two forces P and Q act such that the resultant R is equal to the magnitude of P. If P is doubled, what is the angle made by the new resultant with the force Q?
Answer» Two forces $P$ and $Q$ act such that the resultant $R$ is equal to the magnitude of $P$ . If $P$ is doubled, what is the angle made by the new resultant with the force $Q$ ?

Discussion

45.	The bob of a pendulum at rest is given a sharp hit to impart a horizontal velocity u=√10gl, where l is the length of the pendulum. Then, the tension in the string when it is horizontal is xmg where x=
Answer» The bob of a pendulum at rest is given a sharp hit to impart a horizontal velocity $u = \sqrt{10 g l}$ , where $l$ is the length of the pendulum. Then, the tension in the string when it is horizontal is $x m g$ where $x =$

Discussion

46.	A 50 kg person stands on a 25 kg platform. He pulls on the rope which is attached to the platform via the frictionless pulleys as shown in the figure. The platform moves upward at a steady rate if the force with which the person pulls the rope is
Answer» A $50 kg$ person stands on a $25 kg$ platform. He pulls on the rope which is attached to the platform via the frictionless pulleys as shown in the figure. The platform moves upward at a steady rate if the force with which the person pulls the rope is

Discussion

47.	A ray of light passes through an equilateral glass prism in such a manner that the angle of incidence is equal to the angle of emergence and each of these angles is equal to 34 of the angle of the prism. The angle of deviation is
Answer» A ray of light passes through an equilateral glass prism in such a manner that the angle of incidence is equal to the angle of emergence and each of these angles is equal to $\frac{3}{4}$ of the angle of the prism. The angle of deviation is

Discussion

48.	Consider a straight piece of length x of a wire carrying a current i.Let P be a point on the perpendicular bisector of the piece,situated at a distance d from its middle point.Show that for d>>x,the magnetic field at P varies as 1/d2 whereas d<<x,it varies as 1/d.
Answer» Consider a straight piece of length x of a wire carrying a current i.Let P be a point on the perpendicular bisector of the piece,situated at a distance d from its middle point.Show that for d>>x,the magnetic field at P varies as 1/ $d^{2}$ whereas d<<x,it varies as 1/d.

Discussion

49.	The equation of a wave travelling on a string stretched along the X-axis is given by y=Ae−(xa+tT)2. (a) Write the dimensions of a and T. (b) Find the wave speed. (c) In which direction is the wave travelling ? (d) Where is the maximum of the pulse located at t = T ? At t = 2T ?
Answer» The equation of a wave travelling on a string stretched along the X-axis is given by $y = A e^{- (\frac{x}{a} + \frac{t}{T})^{2}}$ . (a) Write the dimensions of a and T. (b) Find the wave speed. (c) In which direction is the wave travelling ? (d) Where is the maximum of the pulse located at t = T ? At t = 2T ?

49.

The equation of a wave travelling on a string stretched along the X-axis is given by y=Ae−(xa+tT)2. (a) Write the dimensions of a and T. (b) Find the wave speed. (c) In which direction is the wave travelling ? (d) Where is the maximum of the pulse located at t = T ? At t = 2T ?

Answer»

The equation of a wave travelling on a string stretched along the X-axis is given by

$y = A e^{- (\frac{x}{a} + \frac{t}{T})^{2}}$ .

(a) Write the dimensions of a and T. (b) Find the wave speed. (c) In which direction is the wave travelling ? (d) Where is the maximum of the pulse located at t = T ? At t = 2T ?

Discussion

50.	From a given sample of uniform wire, two circular loops P and Q are made, P of radius r and Q of radius nr. If the moment of inertia of Q about its axis is four times that of P about its axis (assuming wire diameter to be much smaller than either radius), the value of n is
Answer» From a given sample of uniform wire, two circular loops P and Q are made, P of radius r and Q of radius nr. If the moment of inertia of Q about its axis is four times that of P about its axis (assuming wire diameter to be much smaller than either radius), the value of n is

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A turn of radius 20 m is banked for the vehicles going at a speed of 36 km/h. If the coefficient of static friction between the road and the tyre is 0.4, what are the possible speeds of a vehicle so that it neither slips down nor skids up ?

A pendulum bob of mass m is attached to the ceiling of a cart which is accelerating with a0 as shown below. Find the angle made by the bob with the vertical.

The dimension J/m2 can correspond to?

A bullet is fired at an angle 60° with the vertical hits the levelled ground at a distance of 200m. Find the distance at which the bullet will hit the ground when fired at an angle of 30° .

Will there there be any interaction between an electric field and a neutral body?

A rectangular lamina in the x−y plane is shown below: Density of this lamina is constant along x axis and varies along y axis. If the variation in density is given as ρ(y)=16ρ0y2, then the coordinates of COM will be

The potential energy for a force field ¯F is given by ∪(x,y) = cos(x+y). The force acting on a particle at position given by coordinates (0, π/4) is

A spherical body radiates 300 W power at 650 K. If the radius were halved and temperature doubled, then find the power radiated.

If external forces acting on a system have zero resultant, the centre of mass a. may move b. may accelerate c. must not move d. must not accelerate

What is the peak voltage across capacitor at resonance frequency in the given circuit ?

What is exited state of an element ? What is ground state of an element ?

A monkey staBeing on the ground wants to climb to the top of a vertical pole of 15m.he climbs 5m in 1s and slips downward 3m in next second. He keeps climbing up in this manner. Find the time taken by the monkey to climb to the top of the pole.

Consider a curved surface between two different media with refractive indices n1 = 1 and n2 = 2. The relation between radius of curvature, image distance and object distance is given by

The number of photons emitted by a bulb or 1.515x10^20 per second.If wavelength of photon is 5000A,what is the power of bulb?

The curie point of cobalt is 1100°c- what is meant by this?

Statements: Some bolts are not cups. All dusters are balls. All bolts are balls. Conclusions: I.All cups are bolts. II.Some dusters are bolts is a possibility.

(243)n5×32n+19n×3n−1=?

There are two particles- an α- particle and a proton. Both are accelerated

Four metal plates numbered 1, 2, 3 and 4 are arranged as shown in Fig. The area of each plate is A and the separation between the plates is d. The capacitance of the arrangement is

In a hydroelectric power station, the height of the dam is 10 m. How many kg of water must fall per second on the blades of a turbine in order to generate 1 MW of electrical power? Take g=10 ms−2.

An electron starting from rest has a velocity that increases linearly with time as v=k t, where k=2ms−2. The distance travelled in the first 3 seconds will be

A force →F=5^i+6^j−4^k acting on a body, produces a displacement →s=6→i+5→k. Work done by the force is

A projectile can have the same range R for two angles of projection. If t1 and t2 are the times of flight in the two cases, then

A small box of mass m is placed on the outer surface of a smooth fixed sphere of radius R at a point where the radius makes an angle ϕ with the vertical. The box is released from this position. Find the distance travelled by the box before it leaves contact with the sphere.

A block of mass 1 kg lies on a horizontal surface in a truck. The coefficient of static friction between the block and the surface is 0.6. If the acceleration of the truck is 5 ms-2, the frictional force acting on the block is

In Young's double slit experiment using two identical slits, the intensity of the maximum at the centre of the screen is I. What will be the intensity at the centre of the screen if one of the slits is closed?

There are two point masses each of mass m are at the ends of a rod of mass m. The rod is released. What will be the angular speed when it becomes vertical?

Two blocks A and B of masses 3 m and m respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively

If the unit of force and length each be increased by four times, then the unit of energy is increased by

The ratio of intensities between two coherent sound sources is 9:1. The difference of loudness in decibels (dB) between maximum and minimum intensities when they interfere in space is

Newton's second law gives the measure of

Two coils A and B have inductances 1.0 H and 2.0 H respectively. The resistance of each coil is 10Ω Each coil is connected to an ideal battery of emf 2.0 V at t = 0. Let iA and iB be the currents in the two cirucit at time t. Find te ration iAIB at (a) t = 100 ms, (b) T = 200 ms and (c) t = 1 s.

An aeroplane is flying at a constant horizontal velocity of 600 km/hr at an elevation of 6 km towards a point directly above the target on the earth’s surface. At an appropriate time, the pilot releases a ball so that it strikes the target at the earth. The ball will appear to be falling

A projectile is projected with initial velocity (6^i+8^j)m/sec. If g=10 ms−2, then horizontal range is

A block hangs from a string wrapped on a disc of radius 20 cm, free to rotate about its axis, which is fixed in a horizontal position. If the angular speed of the disc is 10 rad/s at some instant, with what speed is the block going down at that instant?

A parallel-plate capacitor has plate area 40 cm2, and separation between the plates 0.10 mm is connected to a battery of emf 2.0 V through a 16 Ω resistor. Find the electric field in the capacitor 10 ns after the connections are made.

Equal masses of three liquids A, B and C have temperatures 10∘C, 25∘C and 40∘C respectively. If A and B are mixed, the mixture has a temperature of 15°C. If B and C are mixed the mixture has a temperature of 30∘C. If A and C are mixed, the mixture will have a temperature of

Two metallic slabs of same area of cross section and length having thermal conductivities 300 W/m∘C and 200 W/m∘C respectively are connected in series combination. Find the equivalent thermal conductivity (in W/m∘C)

Define non-uniform circular motion.

Locate the COM of a uniform hemisherical solid with respect to 0 as shown in figure. (Radius = r)

Two forces P and Q act such that the resultant R is equal to the magnitude of P. If P is doubled, what is the angle made by the new resultant with the force Q?

The bob of a pendulum at rest is given a sharp hit to impart a horizontal velocity u=√10gl, where l is the length of the pendulum. Then, the tension in the string when it is horizontal is xmg where x=

A 50 kg person stands on a 25 kg platform. He pulls on the rope which is attached to the platform via the frictionless pulleys as shown in the figure. The platform moves upward at a steady rate if the force with which the person pulls the rope is

A ray of light passes through an equilateral glass prism in such a manner that the angle of incidence is equal to the angle of emergence and each of these angles is equal to 34 of the angle of the prism. The angle of deviation is

Consider a straight piece of length x of a wire carrying a current i.Let P be a point on the perpendicular bisector of the piece,situated at a distance d from its middle point.Show that for d&gt;&gt;x,the magnetic field at P varies as 1/d2 whereas d&lt;&lt;x,it varies as 1/d.

The equation of a wave travelling on a string stretched along the X-axis is given by y=Ae−(xa+tT)2. (a) Write the dimensions of a and T. (b) Find the wave speed. (c) In which direction is the wave travelling ? (d) Where is the maximum of the pulse located at t = T ? At t = 2T ?

From a given sample of uniform wire, two circular loops P and Q are made, P of radius r and Q of radius nr. If the moment of inertia of Q about its axis is four times that of P about its axis (assuming wire diameter to be much smaller than either radius), the value of n is

Consider a straight piece of length x of a wire carrying a current i.Let P be a point on the perpendicular bisector of the piece,situated at a distance d from its middle point.Show that for d>>x,the magnetic field at P varies as 1/d2 whereas d<<x,it varies as 1/d.