The force F → experienced by a particle of charge e moving with velocity v → in a magnetic field B → is given by F → = e ( v → × B → ) . Of these, name the pair of vectors which are always at right angle to each other.

The force F → experienced by a particle of charge e moving with velocity v → in a magnetic field B → is given by F → = e ( v → × B → ) . The pairs F → , e → and F → , B → are always perpendicular to each other. It is because F → will always be at right angle to plane containing e → , B → . In addition, the vector cross product is always perpendicular to each of the vector variables, while the force F → is perpendicular to v → . The electric field and magnetic field will always be perpendicular to each other.

E M B I B E

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 8 - Electromagnetism>EXERCISE 8>Q 21

EASY

12th West Bengal Board

IMPORTANT

Earn 100

Why is an ammeter always connected in series ?

Important Questions on Electromagnetism

EASY

12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 8 - Electromagnetism>EXERCISE 8>Q 22

Why is a voltmeter is joined at two points of an electric circuit ?

EASY

12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 8 - Electromagnetism>EXERCISE 8>Q 23

Why an ammeter should have a low resistance and why is a voltmeter is joined at two points of an electric circuit ?

EASY

12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 8 - Electromagnetism>EXERCISE 8>Q 24

When an ammeter is put in a circuit, does it read slightly less or more than the actual current in the original circuit? Justify your answer.

MEDIUM

12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 8 - Electromagnetism>EXERCISE 8>Q 25

An ammeter and a milliammeter are converted from the same galvanometer. Out of the two, which current measuring instrument has higher resistance?

EASY

12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 8 - Electromagnetism>EXERCISE 8>Q 26

Which one of the following will experience the maximum force when projected with the same velocity

v

perpendicular to the magnetic field (i)

α

-particle (ii)

β

-particle?

EASY

12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 8 - Electromagnetism>EXERCISE 8>Q 27

State the two properties of the material of the wire used for suspension of the coil in a moving coil galvanometer.

EASY

12th West Bengal Board

IMPORTANT

A Text Book of PHYSICS PART 2 : CLASS 12>Chapter 8 - Electromagnetism>EXERCISE 8>Q 28

The force $\vec{F}$ experienced by a particle of charge $e$ moving with velocity $\vec{v}$ in a magnetic field $\vec{B}$ is given by $\vec{F} = e (\vec{v} \times \vec{B})$ . Of these, name the pair of vectors which are always at right angle to each other.