Current Electricity — Physics STD 12 Science — Question

The slope of frequency of incident light and stopping potential graph for  a given surface will be (a) h  (b) h/e (c) eh        (d) e

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.

The maximum focal length of the eye-lens of a person is greater than its distance from the retina. The eye is:

What will be the height of image when an object of 2 mm is placed on the axis of a convex mirror at a distance 20 cm of radius of curvature 40 cm(a) 20 mm(b) 10 mm(c) 6 mm(d) 1 mm

An electric current i enters and leaves a uniform circular wire of radius a through diametrically opposite points. A charged particle q moving along the axis of the circular wire passes through its centre at speed v. The magnetic force acting on the particle when it passes through the centre has a magnitude:

Assertion  : The electromagnetic waves of shorter wavelength can travel longer distances on earth's surface than those of longer wavelengths.
Reason      :  Shorter the wavelength, the larger is the velocity of wave propagation.(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.

When a charged particle moves at right angle to a magnetic field quantity that changes is:

The average binding energy per nucleon in the nucleus of an atom is approximately(a) 8 eV(b) 8 KeV(c) 8 MeV(d) 8 J