Alternating Current — Physics STD 12 Science — Question

A beam of light AO is incident on a glass slab (μ = 1.54)  in a direction as shown in figure. The reflected ray OB is passed through a Nicol prism on viewing through a Nicole prism, we find on rotating the prism that

(a) The intensity is reduced down to zero and remains zero

(b) The intensity reduces down some what and rises again

(c) There is no change in intensity

(d) The intensity gradually reduces to zero and then again increases

What is the coefficient of mutual inductance when the magnetic flux changes by 2   and change in current is 0.01A

(a) 2 henry

(b) 3 henry

(c)  henry

(d) Zero

According to Huygens, the ether medium pervading entire universe is:

If six identical cells each having an e.m.f. of 6V are connected in parallel, the e.m.f. of the combination is

(a) 1 V

(b) 36 V

(c)

(d) 6 V

Which of the following is an electromagnetic wave?

When a drop of oil is spread on a water surface, it displays beautiful colours in daylight because of:

Photo-electric effect can be explained by

(a) Corpusular theory of light	(b) Wave nature of light
(c) Bohr’s theory	(d) Quantum theory of light

A current carrying power line carries current from west to east. Then the direction of the magnetic field 2m above it is:

In parallel combination of capacitors, the effective capacitance:

Suppose the pressure at the surface of mercury in a barometer tube is P₁ and the pressure at the surface of mercury in the cup is P_2,

1. P₁ = 0, P₂ = atmospheric pressure.
2. P₁ = atmospheric pressure P₂ = 0
3. P₁ = P₂ = atmospheric pressure.
4. P₁ = P₂ = 0