Physics
Assertion (A): A freely suspended magnet rests in north-east direction.
Reason (R): Earth has its own magnetic field and the suspended magnet aligns with it.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true and R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Answer
A is false but R is true
Explanation
Assertion (A) is false because a freely suspended magnet does not come to rest in the north-east direction rather it aligns itself along the north–south direction.
Reason (R) is true because the Earth behaves like a giant magnet and has its own magnetic field so a freely suspended magnet aligns itself along this field.
Therefore, A is false but R is true.
Related Questions
The strength of an electromagnet can be increased:
- by increasing the number of turns in the coil.
- by decreasing the number of turns in the coil.
- by inserting a soft iron core in the coil.
- both increasing the number of turns in the coil and inserting a soft iron core.
Identify the correct advantages of dry cells:
- Dry cells are light in weight and small in size.
- There is no fear of leakage in dry cells.
- Dry cells can be easily carried from one place to another.
- All of the above
Assertion (A): In a simple closed circuit made using a torch bulb and an electric cell, electric current flows because tiny particles move inside the wire.
Reason (R): These tiny particles are electrons that drift from the negative terminal of the cell towards the positive terminal outside the cell.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true and R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Fill in the blanks:
(a) A magnet has …………… poles.
(b) Like poles …………… each other and unlike poles …………… .
(c) An electromagnet is used to separate large mass of …………… scrap.
(d) The strength of magnetic field of an electromagnet is increased by inserting a core of …………… .
(e) In a torch, we use …………… as the source of electricity.
(f) To light a table lamp and to run a refrigerator, we use …………… as the source of electricity.
(g) A group of two or more cells is called a …………… .
(h) …………… pass electricity through them.
(i) …………… do not pass electricity through them.