1.
Choose the correct statement:
2.
Fleming's right hand rule gives
3.
By inserting a soft iron piece into a solenoid, the strength of the magnetic field
4.
The force between two parallel wires carrying currents has been used to define
5.
The unit of magnetic flux is
6.
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
7.
The unit of induced emf is
8.
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
9.
If current in the core decreases, the strength of the magnetic field
10.
A compass needle just above a wire in which electrons are moving towards east, will point
11.
A magnetic field cannot exert any force on a
12.
An electric iron draws a current of 4 A when connected to a 220 V mains. Its resistance must be
13.
A magnetic field can exert force on a
14.
Ampere rule is used to find the
15.
The fact that current is associated with a magnetic field was discovered by
16.
It is a common notion that the earth's magnetism is due to the
19.
The resistance of a conductor is reduced to half its initial value. In doing so the heating effects in the conductor will become
20.
By increasing the number of turns in the coil, the strength of the magnetic field
