1.
Fleming's right hand rule gives
2.
The force of repulsion between two parallel wires is f when each one of them carries a certain current /. If the current in each is doubled, the force between them would be
3.
An electric iron draws a current of 4 A when connected to a 220 V mains. Its resistance must be
4.
Ampere rule is used to find the
5.
A magnetic field cannot exert any force on a
6.
A magnetic field can exert force on a
7.
By inserting a soft iron piece into a solenoid, the strength of the magnetic field
8.
The unit of induced emf is
9.
If current in the core decreases, the strength of the magnetic field
11.
The fact that current is associated with a magnetic field was discovered by
12.
Choose the correct statement:
13.
A compass needle just above a wire in which electrons are moving towards east, will point
14.
It is a common notion that the earth's magnetism is due to the
15.
The coil of a heater is cut into two equal halves and only one of them is used in the beater. The ratio of the heat produced by this half of the col to that produced by the original coil is
17.
The unit of magnetic flux is
18.
The force between two parallel wires carrying currents has been used to define
19.
By increasing the number of turns in the coil, the strength of the magnetic field
20.
The resistance of a conductor is reduced to half its initial value. In doing so the heating effects in the conductor will become
