A photon or quantum of light has wavelength ë and frequency f. Its energy is proportional to

1) 1/ë    2) f^1/2     3) the light intensity     4) cë

A jar is filled with two non-mixing liquids 1 and 2 having densities ρ1 and  ρ2 respectively. A solid ball, made of a material of density ρ3 is dropped in the jar. It comes to equilibrium in the position as shown in the figure. Which of the following is true for ρ1,ρ2 and ρ3 ?

1) ρ1 < ρ2 < ρ3

2) ρ1 < ρ3 < ρ2

3) ρ3 < ρ1 < ρ2

4) ρ1 > ρ3 > ρ2

What force is required to give a projectile weighing 450. N an acceleration of 500. m/s²?
 1) 5.6 E 4 N
 2) 2.3 E 4 N
 3) 1.6 E 4 N
 4) 8.7 E 4 N

  If r_p = 3 x 10³ ohm and gm = 20 m. mho if triode is used as an amplifier and RL = 6 kohm, then voltage amplification is

(1) 40
(2) 60
(3) 20
(4) 30

A man of mass 70 kg stands on a weighing scale in a lift. Which is moving upwards with a uniform acceleration of 5 m/s^-2?

The reading on the scale is

1) 35 kg

2) 70 kg

3) 105 kg

4) 120 kg

Two charges, each equal to q, aer kept at x=−a and x=a on the x-axis. A particle of mass m and charge q₀=q / 2 is placed at the origin. If charge q₀ is given a small displacement (y<< a) along the y-axis, the net force acting on the particle is proportional to

1) y
2) −y
3) 1 / y
4) −1 / y

The power of a sound from the speaker of a radio is 20 mW. By turning the knob of the volume control, the power of the sound is increased to 400 mW. The power increase in decibels as compared to the original power is

(1)     13.0 dB                          (2)     10 dB

(3)     20 dB                             (4)     8000 dB

 Distance between earth and moon is reduced to half then the time period will be :

(1) nothing can be said         (2) unchanged

(3) decreases                       (4) increases

 A figure skater has a moment of inertia of 4.0 kg.m² with her arms outstretched. If she begins spin at 3.0 rad/s with her arms outstretched and then brings her arms in tight to her body, her of spin increases to 7.0 rad/s in 2.5 seconds. As the skater brings her arms in tight to her body, what torque is applied to increase her spin.

1) 2.7 N.m

2) 4.0 N.m

3) 5.3 N.m

4) no torque is applied to increase her spin

A cube of aluminum has side length 0.10 m. It is dropped into a deep swimming pool of water with density 1.00 x 10³ kg/m³ . The cube comes gently to rest at the bottom of the pool. If the density of the aluminum is 2.7 x 10³  kg/m3 , the magnitude of the buoyant force acting on the aluminum is:

1) 26.6 N
2) 9.8 N
3) 2.7 N
4) 1.0 N