Vector — JEE physics STD 12 Science — Question

Assertion : A bar magnet is dropped into a long vertical copper tube. Even taking air resistance as negligible, the magnet attains a constant terminal velocity. If the tube is heated, the terminal velocity gets increased.
Reason : The terminal velocity depends on eddy current produced in bar magnet.

Assertion : The water rises higher in a capillary tube of small diameter than in the capillary tube of large diameter.
Reason : Height through which liquid rises in a capillary tube is inversely proportional to the diameter of the capillary tube.

Assertion : The poles of magnet cannot be separated by breaking into two pieces.
Reason : The magnetic moment will be reduced to half when a magnet is broken into two equal pieces.

Assertion : Gravitational force between two particles is negligibly small compared to the electrical force.
Reason : The electrical force is experienced by charged particles only.

Assertion : Moon is seen as it partly reflects the sun light falling on it
Reason : Moon is a satellite of earth. It does not emit light of its own

Assertion : The instantaneous power of an agent is measured as the dot product of instantaneous velocity and the force acting on it at that instant.
Reason : The unit of instantaneous power is watt.

Assertion : The radiation from the sun's surface varies as the fourth power of its absolute temperature.
Reason : The sun is not a black body.

Assertion : All black coloured objects are considered black bodies.
Reason : Black colour is a good absorber of heat.

Assertion : Zener diode works on a principle of breakdown voltage.
Reason : Current increases suddenly after breakdown voltage.