Earth's Magnetic Field

Q.

Which of the following(s) can be used for navigation?

1. Magnetic compass

2. Plastic wire

3. Wooden block

4. Bar magnet

Q. Statement 1 - If a magnet is suspended freely, its north-pole will point toward the geographic north-pole.
Statement 2 - Earth acts as a huge magnet.

1. Both statement 1 and 2 are correct and statement 2 is not the correct explanation of statement 1.
2. Both statement 1 and 2 are correct and statement 2 is the correct explanation of the statement 1.
3. Statement 1 is incorrect and statement 2 is correct.
4. Both statements 1 and 2 are incorrect.

Q.

Geographical south aligns with:

1. South pole of the earth.

2. North pole of the earth.

3. Magnetic north of the earth.

4. None of the above.

Q. Plan a small experiment to prove that Earth acts as a huge bar magnet.

Q.

A compass has a small balanced pointer that always points North-South. This is because:

1. The earth has a magnetic field and the pointer is magnetic

2. Gravity makes the needle point this way

3. The compass needle points to cold places

4. The stars exert a force on the needle

Q.

A magnet in the form of a cube is placed on a piece of cork that floats on water. The cube is marked with four faces W, X, Y and Z and the compass needle points in the direction as shown in the figure. The arrow beside the N symbol represents the direction of the geographical north pole.

Which of the following faces denote the N - pole and S - pole of the magnet?

1. N - pole (W)
   S - pole (X)

2. N - pole (X)
   S - pole (Y)

3. N - pole (Y)
   S - pole (Z)

4. N - pole (Z)
   S - pole (W)

Q.

The geographical direction in which the magnets align themselves when suspended in air is ___ .

1. East-West

2. North-South

3. South-West

4. North-East

Q. The magnetic north pole of Earth is not the same as the geographical North, because_________.

1. Earth’s imaginary bar magnet inside is perfectly aligned to geographical East-West.
2. Earth does not produce magnetic field lines
3. None of the above
4. Earth’s imaginary bar magnet is not aligned to geographic North-South.

Q.

Donald Duck conducted an experiment to test the conductivity of two liquids A and B by using a tester with magnetic needle. Current was passed through both the liquids and it was found that the magnetic needle deflected more in case of Liquid B. Which among these is a poorer conductor and why? [2 MARKS]

Q. Plan a small experiment to prove that Earth acts as a huge bar magnet.

Q.

Study the given statements.
(i) A compass is used to show the directions.
(ii) The needle of a compass is magnetic.
(iii) The needle of a compass always indicates the north and the south directions of the earth.
Identify the correct statements.

1. Only (i) and (ii)

2. Only (ii) and (iii)

3. (i), (ii) and (iii)

4. Only (i) and (iii)

Q. State whether true or false:

1. True
2. False

Q. Which device is used for plotting magnetic field around a bar magnet ?

1. magnetic needle
2. magnetic compass
3. tracing needle
4. none of these