Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

The ratio of secondary to the primary turns in a transformer is 3 : 2. If the power output be P, then the input power neglecting all loses must be equal to

(a) 5 P

(b) 1.5 P

(c) P

(d)

The ratio of the energy of a photon with   to that with   is

(a) 2

(b) 1/4

(c) 4

(d) 1/2

The Lyman transitions involve:

When two identical capacitors are in series have 3mF  capacitance and when parallel 12mF. What is the capacitance of each

(a) 6 μF

(b) 3 μF

(c) 12 μF

(d) 9 μF

Potential energy of a charged conductor is :

Assertion :   Environmental damage has increased the amount of ozone in the atmosphere.

Reason     : Increase of ozone increases the amount of ultraviolet radiation on earth.

(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c) If assertion is true but reason is false.

(d) If the assertion and reason both are false.

The fine structure of hydrogen spectrum can be explained by:

How much current should be passed through acidified water for 100 s to liberate 0.224 litre of

(a) 22.4 A

(b) 19.3 A

(c) 9.65 A

(d) 1 A

Among the two interfering monochromatic sources A and B; A is ahead of B in phase by 66°. If the observation be taken from point P, such that PB – PA = l/4. Then the phase difference between the waves from A and B reaching P is

(a) 156°

(b) 140°

(c) 136°

(d) 126°