50278 + Interview Questions in Physics

1.	A point source S is placed at a height h from the bottom of a vessel of height H(<h). The vessel is polished at the base. Water is gradually filled in the vessel at a constant rate α m3/s. The distance d of image of the source after reflection from the mirror, from the bottom of the vessel will be varies with time t as :
Answer» A point source $S$ is placed at a height $h$ from the bottom of a vessel of height $H (< h)$ . The vessel is polished at the base. Water is gradually filled in the vessel at a constant rate $α m^{3} / s$ . The distance $d$ of image of the source after reflection from the mirror, from the bottom of the vessel will be varies with time $t$ as :

Discussion

2.	38.The position of a body moving along x-axis at time t is given by x=(t²–4t+6)m. The distance travelled by body in time interval t=0 to t=3s is (1) 5m (2) 7m (3) 4m (4) 3m
Answer» 38.The position of a body moving along x-axis at time t is given by x=(t²–4t+6)m. The distance travelled by body in time interval t=0 to t=3s is (1) 5m (2) 7m (3) 4m (4) 3m

Discussion

3.	A man in a balloon rising vertically with an acceleration of 4.9 m/s2 releases a ball 2 s after the balloon is let go from the ground. The greatest height above the ground reached by the ball is (g=9.8 m/s2).
Answer» A man in a balloon rising vertically with an acceleration of $4.9 m / s^{2}$ releases a ball $2 s$ after the balloon is let go from the ground. The greatest height above the ground reached by the ball is $(g = 9.8 m / s^{2})$ .

Discussion

4.	a projectile has same range fir 2 angle of projection. if time of flight n 2 cases ate T1and T2, maximum height is H1 and H2 and the horixontal range is R. then take out range in terms of T1 &T2 . also take out velocity of projection of projectile.also R in terms ot H1 and H2
Answer» a projectile has same range fir 2 angle of projection. if time of flight n 2 cases ate T1and T2, maximum height is H1 and H2 and the horixontal range is R. then take out range in terms of T1 &T2 . also take out velocity of projection of projectile.also R in terms ot H1 and H2

Discussion

5.	A cubical block of ice floating in water has to support a metal piece of mass 0.5 kg. If specific gravity of ice is 0.9, then minimum edge length (in m) of the block so that it does not sink in water is
Answer» A cubical block of ice floating in water has to support a metal piece of mass $0.5 kg$ . If specific gravity of ice is $0.9$ , then minimum edge length (in $m$ ) of the block so that it does not sink in water is

Discussion

6.	In a right angled triangle having hypotenuse 2 units. If θ is included angle and sinθ=12. Find the value of Adjacent side wrt included Angle θ
Answer» In a right angled triangle having hypotenuse 2 units. If $θ$ is included angle and $sin θ = \frac{1}{2} .$ Find the value of Adjacent side wrt included Angle $θ$

Discussion

7.	A charged 30 μF capacitor is connected to a 27 mH inductor. What is the angular frequency of free oscillations of the circuit? [1 Mark]
Answer» A charged $30 μ F$ capacitor is connected to a $27 mH$ inductor. What is the angular frequency of free oscillations of the circuit? $[$ 1 Mark $]$

Discussion

8.	Find the equivalent resistance between points A and B in the circuit shown
Answer» Find the equivalent resistance between points $A$ and $B$ in the circuit shown

Discussion

9.	what is the minimum electrical for e between two charged particles 1 m apart in free space
Answer» what is the minimum electrical for e between two charged particles 1 m apart in free space

Discussion

10.	A diffraction grating is ruled with 600 lines per mm. When monochromatic light falls normally on the grating, the first order diffracted beams are observed on the far side of the grating each making an angle 15∘ with the normal to grating. What is the frequency of the light? (Given sin15∘=0.258)
Answer» A diffraction grating is ruled with $600$ lines per $m m$ . When monochromatic light falls normally on the grating, the first order diffracted beams are observed on the far side of the grating each making an angle $15^{\circ}$ with the normal to grating. What is the frequency of the light? (Given $sin 15^{\circ} = 0.258$ )

Discussion

11.	4. If the mass of neutron is 1.7into 10 to the power _27kg then the de broglie wavelength of neutron of energy 3 ev is
Answer» 4. If the mass of neutron is 1.7into 10 to the power _27kg then the de broglie wavelength of neutron of energy 3 ev is

Discussion

12.	A 3 kg steel ball strikes a wall with a speed of 10 ms−1 at an angle of 60∘ with the surface of the wall. The ball bounce off with the same speed and same angle. If the ball in contact with the wall for 0.25 s. The average force exerted by the wall on the ball is
Answer» A $3 kg$ steel ball strikes a wall with a speed of $10 {ms}^{- 1}$ at an angle of $60^{\circ}$ with the surface of the wall. The ball bounce off with the same speed and same angle. If the ball in contact with the wall for $0.25 s$ . The average force exerted by the wall on the ball is

Discussion

13.	A sphere of radius 4 cm is removed from a sphere of radius 8 cm as shown in figure. If O is the COM of the complete sphere, the position of COM of the remaining sphere will shift towards left from O by
Answer» A sphere of radius $4 cm$ is removed from a sphere of radius $8 cm$ as shown in figure. If $O$ is the $C O M$ of the complete sphere, the position of $C O M$ of the remaining sphere will shift towards left from $O$ by

Discussion

14.	Consider the circuit shown in the figure below:If the input to the ideal op-amp is given as x(t)=1.5u(t) where u(t) is a step function, then the output is represented as
Answer» Consider the circuit shown in the figure below: $If the input to the ideal op-amp is given as x (t) = 1.5 u (t) where u (t) is a step function, then the output is represented as$

Discussion

15.	52. The temperature of two bodies measued by a thermometer are t1=20 degreeC+-0.5degreeC and t2=50degreeC+-0.5degreeC.Calulate the temperature difference and error there in.
Answer» 52. The temperature of two bodies measued by a thermometer are t1=20 degreeC+-0.5degreeC and t2=50degreeC+-0.5degreeC.Calulate the temperature difference and error there in.

Discussion

16.	A boy stands straight in front of a mirror at a distance of 30cm away from it.He sees his erect image whose height is of his real height. The mirror he is using is [MP PMT 1993]
Answer» A boy stands straight in front of a mirror at a distance of 30cm away from it. He sees his erect image whose height is of his real height. The mirror he is using is [MP PMT 1993]

16.

A boy stands straight in front of a mirror at a distance of 30cm away from it.He sees his erect image whose height is of his real height. The mirror he is using is [MP PMT 1993]

Answer»

A boy stands straight in front of a mirror at a distance of 30cm away from it.

He sees his erect image whose height is of his real height. The mirror he is using is

[MP PMT 1993]

Discussion

17.	138.Three particles each with charge 2mc are kept fixed on the vertices of an equilateral triangle of side 1cm the electrostatic potential energy of this system of particles
Answer» 138.Three particles each with charge 2mc are kept fixed on the vertices of an equilateral triangle of side 1cm the electrostatic potential energy of this system of particles

Discussion

18.	43.Explain: The average KE of an ideal gas in calories per mole is approximately equal to three times its absolute temperature.
Answer» 43.Explain: The average KE of an ideal gas in calories per mole is approximately equal to three times its absolute temperature.

Discussion

19.	A harmonic wave has been set up on a very long string which travels along the length of string. The wave has frequency of 50 Hz, amplitude 1 cm and wavelength 0.5 m. For the above described wave.Statement I: Time taken by wave to travel a distance of 8 m along the length of string is 0.32 s.Statement II: Time taken by a point on the string to travel a distance of 8 m, once the wave has reached at that point and sets it into motion is 0.32 s.
Answer» A harmonic wave has been set up on a very long string which travels along the length of string. The wave has frequency of 50 Hz, amplitude 1 cm and wavelength 0.5 m. For the above described wave. Statement I: Time taken by wave to travel a distance of 8 m along the length of string is 0.32 s. Statement II: Time taken by a point on the string to travel a distance of 8 m, once the wave has reached at that point and sets it into motion is 0.32 s.

Discussion

20.	A particle executes simple harmonic motion between x=-A and x=+A. The time taken for it to go from 0 to A/2 is T_1 and to go from A/2 to A is T_{2 } Then:
Answer» A particle executes simple harmonic motion between x=-A and x=+A. The time taken for it to go from 0 to A/2 is T_1 and to go from A/2 to A is T_{2 } Then:

Discussion

21.	1.What is energy density of a wave? 2. What is kinetic energy density of a wave? 3. What is potential energy density of a wave? 4. What is power of wave? 5. What is intensity of wave? 6. What is constructive interference? 7. What is destructive interference? 8. What is difference between constructive and destructive interferences?
Answer» 1.What is energy density of a wave? 2. What is kinetic energy density of a wave? 3. What is potential energy density of a wave? 4. What is power of wave? 5. What is intensity of wave? 6. What is constructive interference? 7. What is destructive interference? 8. What is difference between constructive and destructive interferences?

Discussion

22.	A particle is thrown with a velocity of u m/s. It passes A and B as shown in the figure at time t1=1 s and t2=3 s. The value of u is (g=10 m/s2)
Answer» A particle is thrown with a velocity of $u m / s$ . It passes $A$ and $B$ as shown in the figure at time $t_{1} = 1 s$ and $t_{2} = 3 s$ . The value of $u$ is $(g = 10 m / s^{2})$

Discussion

23.	Question 7 (c)A 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a force of 40000 N and the track offers a friction force of 5000 N, then calculate:(c) the force of wagon 1 on wagon 2.
Answer» Question 7 (c) A 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a force of 40000 N and the track offers a friction force of 5000 N, then calculate: (c) the force of wagon 1 on wagon 2.

Discussion

24.	RMS current of the given saw tooth A.C current is
Answer» RMS current of the given saw tooth A.C current is

Discussion

25.	In the circuit shown in the figure, the galvanometer G shows zero deflection. If the batteries A and B have negligible internal resistance, the value of the resistor R will be
Answer» In the circuit shown in the figure, the galvanometer $G$ shows zero deflection. If the batteries $A$ and $B$ have negligible internal resistance, the value of the resistor $R$ will be

Discussion

26.	For the arrangement shown below a moment of 100 t-m is acting at the common joint 'O'The moment induced in member OB is _____t-m.[Assume EI to be constant for all members]24.74
Answer» For the arrangement shown below a moment of 100 t-m is acting at the common joint 'O' The moment induced in member OB is _____t-m. [Assume EI to be constant for all members] 24.74

Discussion

27.	The longest wavelengthdoublet absorption transition is observed at 589 and 589.6 nm.Calculate the frequency of each transition and energy differencebetween two excited states.
Answer» The longest wavelength doublet absorption transition is observed at 589 and 589.6 nm. Calculate the frequency of each transition and energy difference between two excited states.

Discussion

28.	A round uniform body of radius R, mass M and moment of inertia I, rolls down (without slipping) an inclined plane making an angle θ with the horizontal. Then its acceleration is
Answer» A round uniform body of radius $R,$ mass $M$ and moment of inertia $I$ , rolls down (without slipping) an inclined plane making an angle $θ$ with the horizontal. Then its acceleration is

Discussion

29.	Which of the following metals requires the radiation of highest frequency to cause the emission of electrons?
Answer» Which of the following metals requires the radiation of highest frequency to cause the emission of electrons?

Discussion

30.	An object of mass 5 kg is acted upon by a force that varies with position of the object as shown by the graph. If the object starts from rest at a point x=0, what is its speed at x=50 m
Answer» An object of mass $5 kg$ is acted upon by a force that varies with position of the object as shown by the graph. If the object starts from rest at a point $x = 0$ , what is its speed at $x = 50 m$

Discussion

31.	A satellite orbits the earth at a height of 400 km above the surface. How much energy must be expended to rocket the satellite out of the earth’s gravitational influence? Mass of the satellite = 200 kg; mass of the earth = 6.0 ×1024 kg; radius of the earth = 6.4 ×106 m; G = 6.67 × 10–11 N m2 kg–2.
Answer» A satellite orbits the earth at a height of 400 km above the surface. How much energy must be expended to rocket the satellite out of the earth’s gravitational influence? Mass of the satellite = 200 kg; mass of the earth = 6.0 ×10²⁴ kg; radius of the earth = 6.4 ×10⁶ m; G = 6.67 × 10^–11 N m² kg^–2.

Discussion

32.	A plank of mass m1=8 kg with a bar of mass m2=2 kg placed on its rough surface, lie on smooth floor of elevator ascending with an acceleration g4. The coefficient of friction is μ=15 between m1 and m2. A horizontal force F=30 N is applied to the plank. Then the acceleration of bar and the plank in the reference frame of elevator are: (g=10 m/s2)
Answer» A plank of mass $m_{1} = 8 k g$ with a bar of mass $m_{2} = 2 k g$ placed on its rough surface, lie on smooth floor of elevator ascending with an acceleration $\frac{g}{4}$ . The coefficient of friction is $μ = \frac{1}{5}$ between $m_{1}$ and $m_{2}$ . A horizontal force $F = 30 N$ is applied to the plank. Then the acceleration of bar and the plank in the reference frame of elevator are: ( $g = 10 {m/s}^{2})$

Discussion

33.	A long plank begins to move at t = 0 and accelerates with a speed given by v = (2t^2 + 2) m/s^{-1}. A small block initially at rest on the plank begins to slip at t is equal to (Coefficient of friction between block and plank has μ_s= 0.4 and μ_k = 0.3) (Take g = 10 m/s^2)
Answer» A long plank begins to move at t = 0 and accelerates with a speed given by v = (2t^2 + 2) m/s^{-1}. A small block initially at rest on the plank begins to slip at t is equal to (Coefficient of friction between block and plank has μ_s= 0.4 and μ_k = 0.3) (Take g = 10 m/s^2)

Discussion

34.	A cylindrical vessel is divided in two parts by a fixed partition which is perfectly heat conducting. The wall and piston are thermally insulated from surroundings. The left side contains 0.5 moles of gas with Cv = 2R at temperature of 300 K. The right side contains 4 moles of mixture of gas with Cv = 1.75 R at same temperature of 300 K. The piston compresses slowly the right side from volume of Vo to Vo4. If total change in internal energy of gases is ΔU=n×104J., find n.(Take : R=253 S.I unit)
Answer» A cylindrical vessel is divided in two parts by a fixed partition which is perfectly heat conducting. The wall and piston are thermally insulated from surroundings. The left side contains 0.5 moles of gas with $C_{v}$ = 2R at temperature of 300 K. The right side contains 4 moles of mixture of gas with $C_{v}$ = 1.75 R at same temperature of 300 K. The piston compresses slowly the right side from volume of $V_{o}$ to $\frac{V_{o}}{4}$ . If total change in internal energy of gases is $Δ U = n \times 10^{4} J .$ , find $n$ . (Take : $R = \frac{25}{3}$ S.I unit)

Discussion

35.	An open knife edge of mass 'm' is dropped from a height 'h' on a wooden floor. If the blade penetrates upto the depth 'd' into the wood, the average resistance offered by the wood to the knife edge is
Answer» An open knife edge of mass 'm' is dropped from a height 'h' on a wooden floor. If the blade penetrates upto the depth 'd' into the wood, the average resistance offered by the wood to the knife edge is

35.

An open knife edge of mass 'm' is dropped from a height 'h' on a wooden floor. If the blade penetrates upto the depth 'd' into the wood, the average resistance offered by the wood to the knife edge is

Answer»

An open knife edge of mass 'm' is dropped from a height 'h' on a wooden

floor. If the blade penetrates upto the depth 'd' into the wood, the average resistance offered by the wood to the knife edge is

Discussion

36.	The electric potential difference between two parallel plates is 2000 volt. If the plates are separated by 2 mm what is the magnitude of electrostatic force in Newton on a chargeof 410^-6 C located between the plates? A 4N B 6N C 8N
Answer» The electric potential difference between two parallel plates is 2000 volt. If the plates are separated by 2 mm what is the magnitude of electrostatic force in Newton on a chargeof 410^-6 C located between the plates? A 4N B 6N C 8N

Discussion

37.	The charge on the capacitor in the LC circuit is given by equation d2Qdt2+16Q=0. Find the frequency of LC oscillation.
Answer» The charge on the capacitor in the LC circuit is given by equation $\frac{d^{2} Q}{d t^{2}} + 16 Q = 0$ . Find the frequency of LC oscillation.

Discussion

38.	A wheel is making revolutions about its axis with uniform angular acceleration. Starting from rest, it reaches 100 rev/sec in 4 seconds. Find the angular acceleration. Find the angle rotated during these four seconds.
Answer» A wheel is making revolutions about its axis with uniform angular acceleration. Starting from rest, it reaches 100 rev/sec in 4 seconds. Find the angular acceleration. Find the angle rotated during these four seconds.

Discussion

39.	Let x=A¯¯¯¯¯¯¯¯BC+B¯¯¯¯¯¯¯¯CA+C¯¯¯¯¯¯¯¯AB. Evaluate x when A=1, B=0, C=1.
Answer» Let $x = A ¯ ¯¯¯¯¯¯ ¯ B C + B ¯ ¯¯¯¯¯¯ ¯ C A + C ¯ ¯¯¯¯¯¯ ¯ A B$ . Evaluate $x$ when $A = 1, B = 0, C = 1$ .

Discussion

40.	A particle moves on the x-axis and its velocity varies with time as v(t)=t−t2. Find the time instant when the particle come back to starting point. Also find the distance travelled till then.
Answer» A particle moves on the x-axis and its velocity varies with time as $v (t) = t - t^{2}$ . Find the time instant when the particle come back to starting point. Also find the distance travelled till then.

Discussion

41.	To go home on Christmas Eve, Vinay travels by Bus at 80 km/hr (yes Bangalore bus service is awesome) from office to Bangalore Airport for (13)3 of the total time. Then he travels by flight at 700 km/hr for next (13)3 of time to reach Chennai Airport. Then he takes a cab to his house which travels at 120 km/hr (since its midnight). Find his average speed for the entire journey.
Answer» To go home on Christmas Eve, Vinay travels by Bus at 80 km/hr (yes Bangalore bus service is awesome) from office to Bangalore Airport for $(\frac{1}{3})^{3}$ of the total time. Then he travels by flight at 700 km/hr for next $(\frac{1}{3})^{3}$ of time to reach Chennai Airport. Then he takes a cab to his house which travels at 120 km/hr (since its midnight). Find his average speed for the entire journey.

Discussion

42.	Particle A of mass 1 kg is moving with velocity 2 m/s along positive x-axis. Particle B of mass 3 kg is moving with velocity 4 m/s along positive y-axis. At time t = 0, the co-ordinates (in metre) of A and B are (3, 0) and (0, 8) respectively. The plane is horizontal and coefficient of friction is 0.2. The value of y co-ordinate of centre of mass (in metre), when centre of mass will finally stop (g=10 m/s2).___
Answer» Particle A of mass 1 kg is moving with velocity 2 m/s along positive x-axis. Particle B of mass 3 kg is moving with velocity 4 m/s along positive y-axis. At time t = 0, the co-ordinates (in metre) of A and B are (3, 0) and (0, 8) respectively. The plane is horizontal and coefficient of friction is 0.2. The value of y co-ordinate of centre of mass (in metre), when centre of mass will finally stop $(g = 10 m / s^{2})$ .___

Discussion

43.	A soldier fires a bullet from his rifle towards the target wall. If the mass of the bullet is 30 g and its velocity on leaving the gun is 1080 kmh−1. Find the magnitude of the average resistance force applied by the target wall to stop the bullet in 0.2 seconds.
Answer» A soldier fires a bullet from his rifle towards the target wall. If the mass of the bullet is $30 g$ and its velocity on leaving the gun is $1080 k m h^{- 1}$ . Find the magnitude of the average resistance force applied by the target wall to stop the bullet in $0.2$ seconds.

Discussion

44.	A particle is moving along the path given by y = c6 t6(where c is positive constant). The relation between the acceleration (a) and the velocity (v) of the particle at t=5 sec. Is
Answer» A particle is moving along the path given by y = $\frac{c}{6}$ $t^{6}$ (where c is positive constant). The relation between the acceleration (a) and the velocity (v) of the particle at t=5 sec. Is

Discussion

45.	7. The motion of a particle is given by a = A sinω t + B cosω t. The motion of the particle is (a) not simple harmonic (b) simple harmonic with amplitude A+ B (c) simple harmonic with amplitude (A + B) / 2 (d)simple harmonic with amplitude\sqrt{ A^2+B^2
Answer» 7. The motion of a particle is given by a = A sinω t + B cosω t. The motion of the particle is (a) not simple harmonic (b) simple harmonic with amplitude A+ B (c) simple harmonic with amplitude (A + B) / 2 (d)simple harmonic with amplitude\sqrt{ A^2+B^2

Discussion

46.	Figure shows two projectiles A and B fired simultaneously. Find the minimum distance between them during their flight.
Answer» Figure shows two projectiles $A$ and $B$ fired simultaneously. Find the minimum distance between them during their flight.

Discussion

47.	A linear wire wound potentiometer has a total resistance of 10 kΩ and the maximum power dissipation is limited to 50mW. Assuming maximum premissible excitation voltage has been applied.Find out the output voltage for a input displacement of 12.5 mm. The total length of POT is 50 mm. Output voltage in (Volts) 5.59
Answer» A linear wire wound potentiometer has a total resistance of $10 k Ω$ and the maximum power dissipation is limited to 50mW. Assuming maximum premissible excitation voltage has been applied.Find out the output voltage for a input displacement of 12.5 mm. The total length of POT is 50 mm. Output voltage in (Volts) 5.59

Discussion

48.	There is a uniformly charged non conducting solid sphere made of material of dielectric cons†an t one. If electric potential at infinity be zero, then the potential at its surface is V. If we take electric potential at its surface to be zero, then the potential at the centre will be
Answer» There is a uniformly charged non conducting solid sphere made of material of dielectric cons†an t one. If electric potential at infinity be zero, then the potential at its surface is V. If we take electric potential at its surface to be zero, then the potential at the centre will be

Discussion

49.	Derive the relationshipof number of photons and frequency of two equally energetic beams of lights.if there are n1 of frequency v1 in first beam and n2 photons of frequency v2?
Answer» Derive the relationshipof number of photons and frequency of two equally energetic beams of lights.if there are n1 of frequency v1 in first beam and n2 photons of frequency v2?

Discussion

50.	A car starts from rest to cover a distance s. The coefficient of friction between the road and the tyres is μ. The minimum time in which the car can cover the distance is proportional to
Answer» A car starts from rest to cover a distance $s$ . The coefficient of friction between the road and the tyres is $μ$ . The minimum time in which the car can cover the distance is proportional to

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

38.The position of a body moving along x-axis at time t is given by x=(t²–4t+6)m. The distance travelled by body in time interval t=0 to t=3s is (1) 5m (2) 7m (3) 4m (4) 3m

A man in a balloon rising vertically with an acceleration of 4.9 m/s2 releases a ball 2 s after the balloon is let go from the ground. The greatest height above the ground reached by the ball is (g=9.8 m/s2).

a projectile has same range fir 2 angle of projection. if time of flight n 2 cases ate T1and T2, maximum height is H1 and H2 and the horixontal range is R. then take out range in terms of T1 &T2 . also take out velocity of projection of projectile.also R in terms ot H1 and H2

A cubical block of ice floating in water has to support a metal piece of mass 0.5 kg. If specific gravity of ice is 0.9, then minimum edge length (in m) of the block so that it does not sink in water is

In a right angled triangle having hypotenuse 2 units. If θ is included angle and sinθ=12. Find the value of Adjacent side wrt included Angle θ

A charged 30 μF capacitor is connected to a 27 mH inductor. What is the angular frequency of free oscillations of the circuit? ​​​​​​​[1 Mark]

Find the equivalent resistance between points A and B in the circuit shown

what is the minimum electrical for e between two charged particles 1 m apart in free space

4. If the mass of neutron is 1.7into 10 to the power _27kg then the de broglie wavelength of neutron of energy 3 ev is

A 3 kg steel ball strikes a wall with a speed of 10 ms−1 at an angle of 60∘ with the surface of the wall. The ball bounce off with the same speed and same angle. If the ball in contact with the wall for 0.25 s. The average force exerted by the wall on the ball is

A sphere of radius 4 cm is removed from a sphere of radius 8 cm as shown in figure. If O is the COM of the complete sphere, the position of COM of the remaining sphere will shift towards left from O by

Consider the circuit shown in the figure below:If the input to the ideal op-amp is given as x(t)=1.5u(t) where u(t) is a step function, then the output is represented as

52. The temperature of two bodies measued by a thermometer are t1=20 degreeC+-0.5degreeC and t2=50degreeC+-0.5degreeC.Calulate the temperature difference and error there in.

A boy stands straight in front of a mirror at a distance of 30cm away from it.He sees his erect image whose height is of his real height. The mirror he is using is [MP PMT 1993]

138.Three particles each with charge 2mc are kept fixed on the vertices of an equilateral triangle of side 1cm the electrostatic potential energy of this system of particles

43.Explain: The average KE of an ideal gas in calories per mole is approximately equal to three times its absolute temperature.

A particle executes simple harmonic motion between x=-A and x=+A. The time taken for it to go from 0 to A/2 is T_1 and to go from A/2 to A is T_{2 } Then:

A particle is thrown with a velocity of u m/s. It passes A and B as shown in the figure at time t1=1 s and t2=3 s. The value of u is (g=10 m/s2)

Question 7 (c)A 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a force of 40000 N and the track offers a friction force of 5000 N, then calculate:(c) the force of wagon 1 on wagon 2.

RMS current of the given saw tooth A.C current is

In the circuit shown in the figure, the galvanometer G shows zero deflection. If the batteries A and B have negligible internal resistance, the value of the resistor R will be

For the arrangement shown below a moment of 100 t-m is acting at the common joint 'O'The moment induced in member OB is _____t-m.[Assume EI to be constant for all members]24.74

The longest wavelengthdoublet absorption transition is observed at 589 and 589.6 nm.Calculate the frequency of each transition and energy differencebetween two excited states.

A round uniform body of radius R, mass M and moment of inertia I, rolls down (without slipping) an inclined plane making an angle θ with the horizontal. Then its acceleration is

Which of the following metals requires the radiation of highest frequency to cause the emission of electrons?

An object of mass 5 kg is acted upon by a force that varies with position of the object as shown by the graph. If the object starts from rest at a point x=0, what is its speed at x=50 m

A long plank begins to move at t = 0 and accelerates with a speed given by v = (2t^2 + 2) m/s^{-1}. A small block initially at rest on the plank begins to slip at t is equal to (Coefficient of friction between block and plank has μ_s= 0.4 and μ_k = 0.3) (Take g = 10 m/s^2)

An open knife edge of mass 'm' is dropped from a height 'h' on a wooden floor. If the blade penetrates upto the depth 'd' into the wood, the average resistance offered by the wood to the knife edge is

The electric potential difference between two parallel plates is 2000 volt. If the plates are separated by 2 mm what is the magnitude of electrostatic force in Newton on a chargeof 410^-6 C located between the plates? A 4N B 6N C 8N

The charge on the capacitor in the LC circuit is given by equation d2Qdt2+16Q=0. Find the frequency of LC oscillation.

A wheel is making revolutions about its axis with uniform angular acceleration. Starting from rest, it reaches 100 rev/sec in 4 seconds. Find the angular acceleration. Find the angle rotated during these four seconds.

Let x=A¯¯¯¯¯¯¯¯BC+B¯¯¯¯¯¯¯¯CA+C¯¯¯¯¯¯¯¯AB. Evaluate x when A=1, B=0, C=1.

A particle moves on the x-axis and its velocity varies with time as v(t)=t−t2. Find the time instant when the particle come back to starting point. Also find the distance travelled till then.

A soldier fires a bullet from his rifle towards the target wall. If the mass of the bullet is 30 g and its velocity on leaving the gun is 1080 kmh−1. Find the magnitude of the average resistance force applied by the target wall to stop the bullet in 0.2 seconds.

A particle is moving along the path given by y = c6 t6(where c is positive constant). The relation between the acceleration (a) and the velocity (v) of the particle at t=5 sec. Is

7. The motion of a particle is given by a = A sinω t + B cosω t. The motion of the particle is (a) not simple harmonic (b) simple harmonic with amplitude A+ B (c) simple harmonic with amplitude (A + B) / 2 (d)simple harmonic with amplitude\sqrt{ A^2+B^2

Figure shows two projectiles A and B fired simultaneously. Find the minimum distance between them during their flight.

There is a uniformly charged non conducting solid sphere made of material of dielectric cons†an t one. If electric potential at infinity be zero, then the potential at its surface is V. If we take electric potential at its surface to be zero, then the potential at the centre will be

Derive the relationshipof number of photons and frequency of two equally energetic beams of lights.if there are n1 of frequency v1 in first beam and n2 photons of frequency v2?

A car starts from rest to cover a distance s. The coefficient of friction between the road and the tyres is μ. The minimum time in which the car can cover the distance is proportional to

A charged 30 μF capacitor is connected to a 27 mH inductor. What is the angular frequency of free oscillations of the circuit? [1 Mark]