Wednesday 16 November 2011

Worksheet 36

Activity:

Circle the correct answer.

1. Which of the simple machine helps Ali go faster when he cycles?

A. Gear C. Levers

B. Screws D. Wedges

2. Which characteristic of light causes an eclipse to form?

A. Light can be reflected C. Light consists of seven colours

B. Light is a form of energy D. Light travels in a straight path

3. What is the function of the pulley?

A. To lift heavy objects C. To move objects more quickly

B. To fix two objects together D. To change the direction of moving objects

4. Which of the following are wedges?

A. Saw and tap C. Spanner and screws

B. Ramp and crane D. Chisel and door stopper

5. An eclipse of the Sun can only be observed during the ____________.

A. day C. weekend

B. night D. weekdays

6. What happens during Eclipse of the Sun?

A. The air becomes hot C. The sky becomes dark

B. The sky appears red D. The air becomes dusty


Worksheet 35

Activity:

Fill in the blanks with the correct answer.

1. When waste matter ( ) , poisonous and flammable gases are

released.

2. The microorganisms which disintegrate dead plants, animals and other organic waste are called ( ) .

3. The rubbish that is collected must be burnt in incinerators or placed

in ( ) .

4. Smoke and gases from factories cause ( ) pollution.

5. Air and water pollution can cause ( ) .


Worksheet 34

1. Which of the following is not the advantage of machines?

A. Help to travel

B. Help to know the time

C. Help to move heavy loads

D. Help to increase harmful effect to environment

2. These are the steps to design a machine. Arrange the steps in the

correct order.

I. Identify the problem

II. Build the model as planned

III. Choose the design from the sketches made

IV. Generate a few ideas to make comparisons

A. I, II, III and IV

B. II, III, I and IV

C. I, IV,III and II

D. I, IV, II and III


Choose the true or false for the statements below

1. Machines help us to do things that we cannot do.

True

False

2. Work is done easily without the invention of machines.

True

False

3. We need to make the model before identify the problem we face.

True

False

4. Machines carry us from one place to another, for example, cars, trains, ship and airplanes.

True

False

5. A machine is invented to solve certain problems that we face.

True

False

Worksheet 33

1. Which of the following statements is not true about complex machine?

A. It consists of one simple machine only.

B. It is made up of more than one simple machine.

C. It is more complicated than the simple machine.

D. Examples of complex machine are bicycle and wheelbarrow.

2. Which of the complex machine and its simple machine components is not matched correctly?

Complex machine

Simple machines

Wheelbarrow

Wheel and axle, lever

Bicycle

Wheel and axle, gears

Egg beater

Wedge, gear

Scissors

Lever, wedge