Elasticity — JEE physics STD 12 Science — Question

Assertion : Work and heat are two equivalent form of energy.
Reason : Work is the transfer of mechanical energy irrespective of temperature difference, whereas heat is the transfer of thermal energy because of temperature difference only.

Assertion : A body cannot have energy without having momentum but it can have momentum without having energy.
Reason : Momentum and energy have same dimensions.

Assertion : For the planets orbiting around the sun, angular speed, linear speed, K.E. changes with time, but angular momentum remains constant.
Reason : No torque is acting on the rotating planet. So its angular momentum is constant.

Assertion : Resonance is special case of forced vibration in which the natural frequency of vibration of the body is the same as the impressed frequency of external periodic force and the amplitude of forced vibration is maximum.
Reason : The amplitude of forced vibrations of a body increases with an increase in the frequency of the externally impressed periodic force.

Assertion : A transistor amplifier in common emitter configuration has a low input impedence.
Reason : The base to emitter region is forward biased.

Assertion : Light year and year, both measure time.
Reason : Because light year is the time that light takes to reach the earth from the sun.

Assertion : The minimum number of non coplanar vectors whose sum can be zero, is four.
Reason : The resultant of two vectors of unequal magnitude can be zero.

Assertion : Diamond glitters brilliantly.
Reason : Diamond does not absorb sunlight.

Assertion : Displacement of a body is vector sum of the area under velocity-time graph.
Reason : Displacement is a vector quantity.

Assertion : The scalar product of two vectors can be zero.
Reason : If two vectors are perpendicular to each other, their scalar product will be zero.