Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

Formula for dispersive power is (where symbols have their usual meanings)

(a)

(b)

(c)

(d)

If the speed of light were 2/3 of its present value, the energy released in a given atomic explosion will be decreased by a fraction

(a) 2/3

(b) 4/9

(c) 3/4

(d) 5/9

The interference of light was first demonstrated experimentally by:

Line spectrum contains information about

(a) The atoms of the prism

(b) The atoms of the source

(c) The molecules of the source

(d) The atoms as well as molecules of the source

Two coherent sources of different intensities send waves which interfere. The ratio of maximum intensity to the minimum intensity is 25. The intensities of the sources are in the ratio:

1. 25 : 1
2. 5 : 1
3. 9 : 4
4. 625 : 1

A charged particle moves in a gravity-free space without change in velocity. Which of the following is are possible:

Two charges +4e  and +e are at a distance x apart. At what distance, a charge q must be placed from charge +e so that it is in equilibrium

(a) x/2

(b) 2x/3

(c) x/3

(d) x/6

An electron and a proton with equal momentum enter perpendicularly into a uniform magnetic field, then

(a) The path of proton shall be more curved than that of electron

(b) The path of proton shall be less curved than that of electron

(c) Both are equally curved

(d) Path of both will be straight line

 Identify the type of conductors whose V-I relationship is linear.

A screen is placed a distance 40cm away from an illuminated object. A converging lens is placed between the source and the screen and it is attempted to form the image of the source on the screen. If no position could be found, the focal length of the lens:

1. Must be less than 10cm.
2. Must be greater than 20cm.
3. Must not be greater than 20cm.
4. Must not be less than 10cm.