Atomic and Nuclear Physics — Physics STD 12 Science — Question

Fission of nuclei is possible because the binding energy per nucleon in them(a) Increases with mass number at high mass numbers(b) Decreases with mass number at high mass numbers(c) Increases with mass number at low mass numbers(d) Decreases with mass number at low mass numbers

Intensity of magnetic field due to earth at a point inside a hollow steel box is(a) Less than outside(b) More than outside(c) Same(d) Zero

The energy stored in a 50 mH inductor carrying a current of 4 A will be(a) 0.4 J(b) 4.0 J(c) 0.8 J(d) 0.04 J

The magnetic induction at any point due to a long straight wire carrying a current is(a) Proportional to the distance from the wire(b) Inversely proportional to the distance from wire(c) Inversely proportional to the square of the distance from the wire(d) Does not depend on distance

The ratio of the refractive index of red light to blue light in air is(a) Less than unity(b) Equal to unity(c) Greater than unity(d) Less as well as greater than unity depending upon the experimental arrangement

For harder X-rays:

1. The wavelength is higher.
2. The intensity is higher.
3. The frequency is higher.
4. The photon energy is higher.

The contact force exerted by a body A on another body B is equal to the normal force between the bodies. We conclude that:

1. The surfaces must be frictionless.
2. The force of friction between the bodies is zero.
3. The magnitude of normal force equals that of friction.
4. The bodies may be rough but they don't slip on each other.

Unit of magnetic field is :