- AExist everywhere.
- BExist only in the immediate vicinity of electric charges.
- CExist only when both positive and negative charges are near one another.
- DAre imaginary.
Explanation:
Electric lines of force are imaginary.
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The self inductance of a coil is 5 henry, a current of 1 amp change to 2 amp within 5 second through the coil. The value of induced e.m.f. will be
|
(a) 10 volt |
(b) 0.10 volt |
(c) 1.0 volt |
(d) 100 volt |
For photoelectric emission, tungsten requires light of 2300 Å. If light of 1800 Å wavelength is incident then emission
|
(a) Takes place |
(b) Don’t take place |
|
(c) May or may not take place |
(d) Depends on frequency |
The diagram of a logic circuit is given below. The output F of the circuit is represented by

|
(a) W.(X + Y) |
(b) W.(X.Y) |
(c) W + (X.Y) |
(d) W + (X + Y) |
and
ions having same kinetic energy pass through a region of space filled with uniform magnetic field B directed perpendicular to the velocity of ions. The masses of the ions
and
are respectively in the ratio 1 : 4 : 16. As a result
|
(a) |
|
(b) |
|
(c) All ions will suffer the same deflection |
|
(d) a, b |
The transformation ratio in the step-up transformer is
|
(a) 1 |
|
(b) Greater than one |
|
(c) Less than one |
|
(d) The ratio greater or less than one depends on the other factors |
When two magnetic moments are compared using equal distance method the deflections produced are 45o and 30o. If the length of magnets are in the ratio 1 : 2, the ratio of their pole strengths is
|
(a) 3 : 1 |
(b) 3 : 2 |
(c) |
(d) 2 |
The relationship between λ and half life (
of a radioactive substance is
|
(a) λ = |
(b) λ = |
(c) λ = |
(d) λ = |