Rotational Dynamics — Physics STD 12 Science — Question

Write notes on: (a) Nuclear fission (b) Nuclear fusion.

State an expression for the radius of gyration of
(i) a thin ring
(ii) a thin disc, about respective transverse symmetry axis.
OR
Show that for rotation about respective transverse symmetry axis, the radius of gyration of a thin disc is less than that of a thin ring.

A capacitor has some dielectric between its plates and the capacitor is connected to a DC source. The battery is now disconnected and then the dielectric is removed. State whether the capacitance, the energy stored in it, the electric field, charge stored and voltage will increase, decrease or remain constant.

Prove that all harmonics are present in the vibrations of the air column in a pipe open at both ends.

State the laws of simple pendulum.

Explain the following characteristics of sound :
(1) loudness
(2) pitch
(3) quality or timbre.

Derive an expression for the effective or equivalent capacitance (capacity) of a combination of a number of capacitors connected in series.
OR
Derive an expression for the effective capacitance of three capacitors connected in series.

Explain gauge pressure and absolute pressure within a liquid open to the atmosphere.
OR
Explain the effect of gravity on fluid pressure.

Derive an expression for the net rate of loss of heat per unit area by a perfect blackbody in a cooler surroundings.