Name: Date: Write down the correct letter for each of the following questions. You must choose one answer only.

Transcription

1 Form 3 Science Test Test 6: Force, energy and motion Total: 50 marks Name: ate: Section Write down the correct letter for each of the following questions. You must choose one answer only. 1. Who developed the Laws of Motion? Sir drian Newton Sir Isaac Newton Galileo Galilei Kelvin 2. hoose the correct answer. Newton s Laws of Motion predict and explain why things move fast, move slowly or stop moving. In terms of Newton s Second Law of Motion, a force changes the movement of an object. Newton s Third Law of Motion states that all moving objects move at a constant speed. ll of the above. 1/6 Pearson otswana. Permission is given to photocopy these pages for school use.

2 3. hoose the correct answer. ir resistance is a form of friction. Friction is the force that makes moving objects come to a stop. Friction will be low when the ground is slippery. ll of the above. 4. hoose the correct answer. If a ball is moving in the air, it will eventually fall to the ground due to the force of gravity. If a ball is moving in the air, it will eventually fall to the ground due to the force of friction. Gravity is the force that ensures that the planets move in circles around the moon and not in a straight line. Gravity is the force that ensures that the planets move in a straight line. 5. hoose the correct answer. The velocity of an object is how fast it is going. The velocity of an object is how slow it is going. Velocity is when we multiply the mass of something with its height. oys naturally have a greater velocity than girls. 6. What is momentum? The speed at which we move The answer we get when we multiply the mass of something by its velocity The answer we get when we divide the mass of something by its velocity None of the above. 2/6 Pearson otswana. Permission is given to photocopy these pages for school use.

3 7. hoose the correct answer. Forces do not work on their own. Forces act in pairs. When an object exerts a force on another object, the second object will exert an equal but opposite force the first object. ll of the above. 8. What is the SI unit of force? The metre The joule The Newton The Kelvin 9. What instrument is used to measure force? thermometer forcemeter forceps hydrometer 10. hoose the correct answer. The formula for force is F = x where F stands for force, stands for mass and for acceleration. The formula for force is F = x where F stands for force, stands for momentum and for acceleration. The formula for force is F = x where F stands for force, stands for mass and for altitude. The formula for force is F = x where F stands for friction, stands for mass and for acceleration. [10] 3/6 Pearson otswana. Permission is given to photocopy these pages for school use.

4 Section 11. Explain Newton s First Law of Motion, by providing an example from everyday life. (4) 12. Explain Newton s Second Law of Motion by proving an example from everyday life. (4) 13. Explain Newton s Third Law of Motion by providing an example from everyday life. (4) 4/6 Pearson otswana. Permission is given to photocopy these pages for school use.

5 14. If a runner has a mass of 80 kg, what is the force he will have to exert to move at an acceleration of 5 m/s? (4) 15. Kagiso is a tennis player. What acceleration will she give to a ball with a mass of 200 g when she hits it with a force of 100 N? (4) [20] Section 16. Write out an experiment you would conduct to show what causes a ball to bounce off a wall. Explain your findings in terms of what you know about force. (10) 5/6 Pearson otswana. Permission is given to photocopy these pages for school use.

6 17. There is no application for Science in everyday life. Write a short paragraph to disprove this statement. Use examples from what you have learnt about force to support your answer. (10) [20] Total: 50 6/6 Pearson otswana. Permission is given to photocopy these pages for school use.