1.State Flemings left hand rule?

Stretch for finger, the middle finger and the thumb of the left hand in mutually perpendicular directions. If,

• Fore finger points the direction of magnetic field,
• The middle finger points the direction of the electric current, then
• Thumb will point the direction of the force experienced by the conductor.

2.Explain the concept of velocity selector?

By proper choice of electric and magnetic fields, the particle with particular speed can be selected. Such an arrangement of fields is called a velocity selector.

3.State ampere circutal law?

The line integral of magnetic field over a closed loop is μ0 times net current enclosed by the loop.

where I_enclosed is the net current linked by the closed loop C.

4.Give the properties of dia magnetic materials?

The properties of diamagnetic materials are

1. Magnetic susceptibility is negative.
2. Relative permeability is slightly less than unity.
3. The magnetic field lines are repelled or expelled by diamagnetic materials when placed in a magnetic field.
4. Susceptibility is nearly temperature independent.

5.Is ammeter connected in series or parallel in a circuit?why?

The ammeter must offer low resistance such that it will not change the current passing through it. So ammeter is connected in series to measure the circuit current.

6.What are the limitations of cyclotron?

• The speed of the ion is limited
• Electron cannot be accelerated
• Uncharged particles cannot be accelerated

7.What is magnetic permiability?

The magnetic permeability is the measure of ability of the material to allow the passage of magnetic field lines through it

In free space,

The permeability (or absolute permeability) is denoted by µ₀ and for any other medium it is denoted by µ

8.How will you increase the current sensitivity of a galvanometer?

The current sensitivity of a galvanometer can be increased by

• Increasing the number of turns, N
• Increasing the magnetic induction, B
• Increasing the area of the coil, A
• Decreasing the couple per unit twist of the suspension wire, K.