Electromagnetic Induction — Physics STD 12 Science — Question

The three vessels shown in fisure (13- Q2) have same base area. Equal volumes of a liquid are poured in the three vessels. The force on the base will be:

1. Maximum in vessel A.
2. Maximum in vessel B.
3. Maximum in vessel C.
4. Equal in all the vessels.

An electron enters between two horizontal plates separated by 2mm and having a potential difference of 1000V. The force on electron is

(a) 8

(b) 8 N

(c) 8

(d) 8

 and  ions are projected on the photographic plate with same velocity in a mass spectrograph. Which one will strike farthest

(a)

(b)

(c)

(d)

Two wires ‘A’ and ‘B’ of the same material have their lengths in the ratio 1 : 2 and radii in the ratio 2 : 1. The two wires are connected in parallel across a battery. The ratio of the heat produced in ‘A’ to the heat produced in ‘B’ for the same time is

(a) 1 : 2

(b) 2 : 1

(c) 1 : 8

(d) 8 : 1

Penetrating power of X-rays does not depend on

(a) Wavelength	(b) Energy
(c) Potential difference	(d) Current in the filament

A 25 W, 220 V bulb and a 100 W, 220 V bulb are connected in parallel across a 440 V line

(a) Only 100 watt bulb will fuse	(b) Only 25 watt bulb will fuse
(c) Both bulbs will fuse	(d) None of the bulbs will fuse

Two parallel circular coils of equal radii having equal number of turns placed coaxially and separated by a distance equal to the radii of the coils carrying equal currents in same direction are known as:

A point object O is placed in front of a glass rod having spherical end of radius of curvature 30 cm.  The image would be formed at

(a) 30 cm left

(b) Infinity

(c) 1 cm to the right

(d) 18 cm to the left

A moving coil galvanometer has 150 equal divisions. Its current sensitivity is 10 divisions per milliampere and voltage sensitivity is 2 divisions per millivolt. In order that each division reads 1 volt, the resistance in ohms needed to be connected in series with the coil will be

(a) 99995

(b) 9995

(c)

(d)