Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

When the current through the electromagnet of a relay reaches a particular value:

A thin prism  with angle 6° and made from glass of refractive index 1.54 is combined with another thin prism P₂ of refractive index 1.72 to produce dispersion without deviation. The angle of prism   will be

(a) 5° 24’

(b) 4° 30’

(c) 6°

(d) 8°

A piece of charcoal and a piece of shining steel of the same surface area are kept for a long time in an open lawn in bright sun:

1. The steel will absorb more heat than the charcoal.
2. The temperature of the steel will be higher than that of the charcoal.
3. If both are picked up by bare hands, the steel will be felt hotter than the charcoal.
4. If the two are picked up from the lawn and kept in a cold chamber, the charcoal will lose heat at a faster rate than the steel.

Bartholinus discovered:

Two point white dots are 1mm apart on a black paper. They are viewed by eye of pupil of diameter 3mm. Approximately what is the maximum distance up to which these dots can be resolved by the eye.

If   and   are the electric and magnetic field vectors of E.M. waves then the direction of propagation of E.M. wave is along the direction of

(a)

(b)

(c)

(d) None of these

For nuclei with A > 100:

1. The binding energy of the nucleus decreases on an average as A increases.
2. The binding energy per nucleon decreases on an average as A increases.
3. If the nucleus breaks into two roughly equal parts, energy is released.
4. If two nuclei fuse to form a bigger nucleus, energy is released.

In a microscope, the focal length of the objective lens in comparison to focal length of the eye lens is :

When a test charge is brought from infinity to near the dipole along the neutral line of an electric dipole, then the work done will be: