Monday, 28 December 2020

Chapter 13 Fun With Magnets

0 comments

Chapter 13 – fun with magnets

 

ACTIVITY- 1 : To separate magnetic and non-magnetic materials.

 

Question 1- Materials attracted by a magnet are called _______ (Magnetic/Non-magnetic).

Answer- Magnetic.

 

Question 2- Materials not attracted by a magnet are called _______ (Magnetic/Non-magnetic).

Answer- Non-magnetic.

 

ACTIVITY- 3 : A freely suspended bar magnet always comes to rest in

North-South direction. (Page No.- 136)

 

Question 1- A freely suspended bar magnet always points towards direction:

(a) North-South () (b) East-west

 

ACTIVITY- 4 : To locate the position of magnetic poles.

 

Question 1- The poles of a bar magnet are ________ to its ends. (Near/far)

Answer- Near.

 

Question 2- Bar magnet has ______ poles.

Answer- Two.

 

ACTIVITY- 6 : Make your own Compass.

 

Question 1- Magnetic compass is a device to find the ________ of earth. (directions / time)

Answer- Directions.

 

ACTIVITY- 7 : Attraction and repulsion between magnets.

 

Question 1- Like poles of two magnets _________ each other. (Repel, Attract)

Answer- Repel.

 

Question 2- Unlike poles of two magnets _________ each other. (Repel, Attract)

Answer- Attract.

 

EXERCISE

 

Question 1- Fill In The Blanks.

a). Magnetite is natural magnet.

b). Plastic is not a magnetic material.

c). A magnet has two poles.

d). The poles of a bar magnet are at its ends.

e). Compass is used for finding directions on earth.

 

Question 2- Write True Or False.

 

a). Poles of a magnet can be separated. (False)

b). A magnet does not attract glass material. (True)

c). Magnet can damage memory devices. (True)

d). Magnetic compass always point towards East-West direction. (False)

e). Magnets lose their property on hammering. (True)

 

Question 3- Match The Column:-

 

Column A             Column B

 

1. Wood                     a. Repel.  (3)

2. Iron                        b. Natural magnet (4)

3. North pole-North pole   c. Non-magnetic material (1)

4. Magnetite                  d. Attract (5)

5. North pole-South pole      e. Magnetic material (2)

 

Question 4. Choose The Correct Answer.

 

(i). Non-magnetic material is:

a) Iron

b) Needle

c) Paper ()

d) None of them

 

(ii). Which can be converted into magnet:

a) Eraser

b) Iron nail ()

c) wooden bar

d) None of these

 

Question 5- Very Short Answer Type Questions.

 

(i) Write name of any two things used in our daily life that contains magnet?

Answer- Door catcher, mobile cover, speaker, purse etc.

 

(ii) When a bar magnet placed on iron fillings, where the fillings will be attracted more?

Answer- Near the ends of bar magnet i.e. at poles.

 

(iii) What is an artificial magnet?

Answer- Man made magnets are called artificial magnet.

 

(iv). Write any two properties of magnet?

Answer- (i) Magnet aligns in North-South direction when suspended freely.

(ii) A magnet has two magnetic poles.

 

 

Question 6- Short Answer Type Questions.

 

(i) What is a magnet? Name the poles of magnet?

Answer- A magnet is a substance which attracts iron like things towards it. Magnet has two poles i.e. North pole and South pole.

 

(ii) Give three reasons by which a magnet loses its property?

Answer- Magnet can lose its property by heating, by hammering and by throwing from height.

 

(iii) What is a compass? For what purpose it is used?

Answer- Magnetic compass is a device made up of magnetic needle, that is used to find geographical directions on earth.

 

(iv). What are magnetic and non-magnetic materials? Give examples?

Answer- Magnetic materials- Materials like iron, nickel and cobalt are attracted towards magnet. These are called magnetic materials.

Non-magnetic materials- Materials like plastic, glass and wood are not attracted towards magnet.These are called non-magnetic materials.

 

Question 7- Long Answer Type Questions.

 

(i) How will you make your own magnet from a given strip of iron? Describe.

Answer- Rub the iron strip with a bar magnet in one direction about 40-50 times. The iron strip will attain the property of magnet.

 

(ii) Give some uses of magnets in our daily life?

Answer- (1) All speakers and head phones have magnets.

(2) Electric bell works with electric magnet.

(3) Door catchers also have magnets.

(4) Buckles of some mobile covers and purses also has magnets.

(5) Pin holders also have magnet due to which pins stick to the holder.