The figure given above shows the temperature (T) - time (t) plot when we start heating a piece of naphthalene. The temperature (T) at the plateau of the curve signifies

• boiling point of naphthalene

• freezing point of naphthalene

• melting point of naphthalene

• the temperature when naphthalene undergoes a chemical change upon heating

A piece of paper and a coin both having the same mass are dropped from the 10 floor of a building. The piece of paper would take more time to reach the ground because

• gravitational pull on the paper is less than the coin

• buoyant force on the piece of paper is more than that on the coin

• buoyant force on the coin is more and acts in the downward direction

• the piece of paper takes a longer path to reach the ground

Ohm's law can also be taken as a statement for

• conservation of energy

• conservation of electric charge

• conservation of angular momentum

• non-conservation of momentum of the flowing charges

Motion of a particle can be described in x-direction by x = a sin wt, and y-direction by y= b cos wt. The particle is moving on

• a circular path of radius 'a'

• a circular path of radius 'b'

• an elliptical path

• a straight line

A bullet of mass 20 gm is fired in the horizontal direction with a velocity 150 mis from a pistol of mass 1 kg. Recoil velocity of the pistol is

• 3 m/s

• 3 km/s

• 300 m/s

• 113 m/s

256.

What should be the reading of the voltmeter V in the circuit given above?

(All the resistances are equal to 12 and the battery is of 1.5 volt)

• 1.5 volt

• 0.66 volt

• 1 volt

• 2 volt

The plot given above represents the velocity of a particle (in mis) with time (in seconds). Assuming that the plot represents a semi-circle, distance traversed by the particle at the end of 7 seconds is approximately.

• 19 m

• 7 m

• 3.2 m

• 4.75 m

Suppose we have an iron nail and an iron ball of same mass. When submerged in water, the iron ball may float but the nail always sinks. This is because

• buoyant force on the ball is larger than that of the nail due to their shapes

• viscous force on the ball is higher

• viscous force on the nail is higher

• gravitational force affects the ball differently from the nail

An electric heater is rated 1500 watt. If electric power costs 2 per kilo-watt-hour, then the cost of power for 1O hours running of the heater is

• Rs 30

• Rs 15

• Rs 150

• Rs 25

Which one among the following situations is best represented by the velocity - time plot shown above?

• Uniform motion of a particle on a circle

• Accelerated motion of a particle which has a nonzero initial velocity

• Decelerated motion of a particle which has an initial non-zero velocity

• Decelerated motion of a particle which has no initial velocity