1.State 3 possible effects of a force Change an objects Shape Speed Direction answer

. 2.Define the gravitational field strength of a planet. answer The force of gravity acting on a mass of one kilogram.

3.Write down a relationship between weight, gravitational field strength and mass. Weight = mass x gravitational field strength answer

4. An object is travelling at 2ms -1 when the forces on it become balanced. Describe how the object now moves. The object continues to move in a straight line with a constant speed of 2ms answer

5.An object of mass of 2kg has an acceleration of 3 ms -2. What unbalanced force is acting on the object? F = ma F= 2 x 3 F = 6N answer

6.A person transfers 50J of energy when pushing an object 2m along a bench. What was the force exerted? E W = F x d 50 = F x 2 F = 25N answer

7. A machine transfers 800J of energy in a time of 40 seconds. Find the power output. P = E/t P = 800/40 P = 20W answer

8.State the equations which allow us to calculate kinetic and potential energy. Potential Energy E P = mgh Kinetic EnergyE K = ½ mv 2 answer

9. How much potential energy does a 5kg mass gain when it is lifted through 2m? E P = mgh E P = 5 x 9.8 x 2 E P = 98J answer

10. An object of mass 3kg has a speed of 2ms -1. Calculate its kinetic energy. E K = ½ mv 2 E K = ½ x 3 x 2 2 E K = 6J answer

11.An object gains 100J of potential energy when it is lifted from the ground. It is then dropped. Assuming no air resistance, what will be its kinetic energy when it hits the ground? 100J. All of the potential energy is converted to kinetic. answer

12.State the difference between scalars and vectors A scalar has magnitude (size) only but a vector has magnitude and direction. answer

13. Divide the following quantities into scalars and vectors. Force, mass, time, weight, velocity, energy, speed, displacement SCALARS mass, time, energy, speed VECTORS force, weight, velocity, displacement answer

14. An object falls freely towards the earth. What is its acceleration? 9.8ms -2 answer

15. When a rocket lifts off it pushes hot gases downwards. Why does the rocket move up? The hot gases exert an upward force on the rocket. ( Newton’s 3 rd Law) answer

16. A model rocket has a weight of 2N. It produces a thrust of 8N. What is the unbalanced force acting on the rocket? 6N answer

17. Why does a projectile follow a curved path? A projectile has both a horizontal and vertical motion. It moves across and down at the same time. answer

18. Describe the horizontal and vertical motions of a projectile. HORIZONTAL constant speed VERTICAL constant acceleration( 9.8ms -2 ) answer

19. A ball is fired from a platform. Increase the height of the platform. Increase the horizontal speed of the cannonball. answer State two ways of increasing the horizontal range.

20. A ball is kicked off a roof with a horizontal speed of 7ms -1 It hits the ground 2seconds later. How far from the is the roof when it lands? d = v x t d = 7 x 2 d = 14m answer

21. An object is dropped from a tall building and hits the ground 3 seconds later. Find its speed on hitting the ground. answer a = (v-u)/t 9.8 = (v-0)/3 v = 29.4 ms -2

22. How long does a geostationary satellite take to make one orbit of the earth? answer 24 hours