Page 239 - New Medley 5 Semester 2

C. Answer these questions.

1. De ne force. What are the possible e ects of force?

2. De ne buoyant force and frictional force.
3. What is an inclined plane? Where and how is it used?
4. What are the major groups of simple machines?

5. How are wheel and axle important to us?

D. Life Skills

You see di erent types of instruments in your house like scissors, nut cracker, stapler,

etc. Look other instruments and categorise them into simple or complex machines.

Think and Answer • Critical Thinking

1. It is easy to li a bucket of water out of a well with the help of a pulley. Why?
2. Why does a rolling ball stop itself even if no external force is applied on it?

3. How do swimming rings prevent a swimmer from drowning?

Let Us Do S E L Self-Management • Creativity

Make the model of a screw.

Take a paper and cut it in the form of
a right-angled triangle. One of its sides
will represent an inclined plane. Colour  
this edge. Now, wrap this paper around

a pencil as shown in the gure.
Your model of screw is ready.

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