Mutual inductance of two coils can be increased by

• decreasing the number of turns in the coils

• increasing the number of turns in the coils

• winding the coils on wooden cores

• None of these

Assertion:  If a heavy nucleus is split into two medium-sized parts, each of the nuclei will have more binding energy per nucleon than the original nucleus. 

Reason:  Joining two light nuclei together to give a single nucleus of medium size means more binding energy per nucleon than the two nucleus.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false.

• If both assertion and reason are false.

n-alpha particles per second are emitted from N atoms of a radioactive element. The half-life of the radioactive element is

• $\frac{\mathrm{n}}{\mathrm{N}} \mathrm{s}$

• $\frac{\mathrm{N}}{\mathrm{n}}\mathrm{s}$

• $\frac{0.693 \mathrm{N}}{\mathrm{n}} \mathrm{s}$

• $\frac{0.693 \mathrm{n}}{\mathrm{N}} \mathrm{s}$

Assertion:  The ratio for time taken for light emission from an atom to that for release of nuclear energy in fission is 1 : 100. 

Reason:  Time taken for the light emission from an atom is of the order of 10^-8 s.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion:  Static crashes are heard on radio, when lightning flash occurs in the sky. 

Reason:  Electromagnetic waves having frequency of radio wave range interfere with radio waves.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion:  γ-radiation emission occurs after $\mathrm{\alpha } \mathrm{and} \mathrm{\beta }$ decay. 

Reason: Energy levels occur in nucleus.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

In nuclear fission, which of the following quantity is conserved?

• Energy

• Mass

• Momentum

• Both energy and mass

When a slow neutron is captured by a ${}_{92}{}^{235}\mathrm{U}$ nucleus, a fission energy releasing 200 MeV. If power of nuclear reactor is 100 W then rate of nuclear fission is

• 3.6 × 10⁶ s^-1

• 3.1 × 10¹² s^-1

• 1.8 × 10⁴ s^-1

• 4.1 × 10⁶ s^-1

Which of the following statement is incorrect?

• Neutron is less stable than proton

• Neutron can cause fission in nuclear reactors but proton can not.

• A free proton can emit beta particle.

• A bound proton can emit beta particle.

210.

Electric field at a distance r from infinitely long conducting sheet is proportional to

• r^-1

• r^-2

• r^-3/2

• independent of r