# Beath High School - Int 1 Physics

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Beath High School - Int 1 Physics
Intermediate 1 Physics Movement Questions and Answers Beath High School - Int 1 Physics

Intermediate 1 Physics Movement Questions 1 to 13 Questions 14 to 26
(Forces) Questions 14 to 26 (speed & acceleration) Questions 27 to 35 (Moving bodies) Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
1. Describe how to use a newton balance. Use a diagram in your answer. Hold the balance steady, for example by attaching it to a fixed support. Hang the object to be weighed on the balance. Take a reading of the weight from where the pointer is on the scale. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
2. Calculate the weights of the following objects: (a) a 1 kg bag of sugar Weight = mass x g = 1 x 10 = 10 newtons (b) a person of mass 75 kg Weight = m x g = 75 x 10 = 750 newtons (c) a 0.1 kg apple Weight = mg = 0.1 x 10 = 1 N (d) a 420 g can of beans Weight = mg = 0.42 x 10 = 4.2 N (e) a 35 g packet of crisps W = mg = x 10 = 0.35 N Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
3. Susan feels she gets far too much homework. She decides to pile all her homework for a month into a barrow and weigh it. However, she finds that she has to stand on the weighing machine herself or else the barrow will tip over. The combined weight of Susan, the barrow and the month's homework is 670 newtons. Susan knows her own mass, is 55 kg and the mass of the barrow is marked on it as 8 kg. Calculate the mass of homework Susan does in a month. Mass of (Susan + barrow + homework) = weight/10 = 670/10 = 67 kg Mass of homework = total mass – (55 + 8) = 67 – (63) = 4 kg Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
4. An astronaut has a mass of 70 kg. When far out in space the astronaut has no weight, but is still 70 kg. Explain why it is possible for the astronaut to have no weight, but still have mass. Weight is the force of attraction a planet exerts. Far out in space there is no planet to attract the astronaut; so he/she has no weight. Mass (which is measured in kilograms) is a measure of the amount of substance in an object and so cannot change wherever it is. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
5. The diagram below shows two identical boxes, A and B, suspended by identical springs. One box contains 50 pound coins, the other contains 50 pennies. Which box contains the £50? Explain your choice. The spring holding box B has stretched more than A. This means that box B must be heavier than A. Therefore, box B contains the 50 pound coins, because pound coins weigh more than pennies. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
6. Complete the following sentences: Friction is a force caused by the of two surfaces. rubbing Friction opposes the of an object. motion Friction can also keep objects from starting to move Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
7. Friction is not always a bad thing. In many situations we want to use the force of friction. What role does the force of friction play in the following cases? (a) Opening a tight bottle top or jam jar lid The force of friction between your hand and the lid gives you a good grip. (b) Sanding wood It helps wear the wood down to a smooth surface. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
7. Friction is not always a bad thing. In many situations we want to use the force of friction. What role does the force of friction play in the following cases? (c) Sports shoes on gym floors The force of friction between the shoes and the floor gives a good grip. (d) Walking on icy pavements It helps give a good grip and prevent slipping. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
7. Friction is not always a bad thing. In many situations we want to use the force of friction. What role does the force of friction play in the following cases? (e) Warming hands by rubbing The force of friction changes the kinetic energy to heat. (f) Striking a match The friction with the rough surface produces enough heat to light the match. (g) Car tyres for wet conditions It helps the tyres get a good grip on the road. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
8. Often we want to reduce the force of friction. How is it reduced in the following cases? (a) Metal engine parts moving against each other Oil is used as a lubricant, allowing the surfaces to slip over each other. (b) A hovercraft The hovercraft ‘floats’ along on a cushion of air which separates it from the ground. (c) Skates on ice The ice is a smooth, slippery surface. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
8. Often we want to reduce the force of friction. How is it reduced in the following cases? (d) Door hinges Oil is used as a lubricant, allowing the surfaces to slip over each other. (e) Air resistance of a racing cyclist The cyclist bends forward to reduce air resistance. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
9. What force is streamlining designed to reduce? Air resistance Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
10. Car manufacturers try to improve the streamlining of their cars. (a) Why is it useful for cars to be streamlined? It helps them cut through the air more easily. This allows them to go faster and use less fuel. (b) What are the two main things done to a car to improve streamlining? They are smoothly shaped like a teardrop. They are often fitted with spoilers at the back. They run close to the road. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
11. The picture shows an astronaut with a jet pack. The astronaut is on Earth during training for a space mission and is hovering in mid air. (a) The diagram shows two forces as arrows. Name these forces. Down force = weight Up force = thrust of jet engine (b) How do the values of these forces compare with each other? They are equal in size (and opposite in direction), since the astronaut is not accelerating. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
11. The picture shows an astronaut with a jet pack. Later, when far away in space, the astronaut fires his jet pack in the same way as on Earth training but finds that he moves away from the space craft. (c) Explain why he does not hover on this occasion. There is no weight in deep space to balance the thrust of the jet engine. The astronaut has an unbalanced force acting and so accelerates. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
12. In tug-of-war games both teams are often pulling. Explain why neither team moves. The forces are balanced because they are equal and opposite. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
13. A skydiver is falling at a very high constant speed - before she opens her parachute. (a) What force pulls her towards the ground? Her weight. i.e. the attractive force due to gravity. (but not just ‘gravity’) (b) What is the name of the force that is balancing this? air resistance (c) How does the sky diver use friction to reduce this high speed before reaching the ground? opening the parachute causes the air resistance upwards to be much bigger than her weight down. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
14. What two measurements must be taken before you can calculate the average speed of a moving object? the total distance travelled the total time taken to travel that distance Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
15. You are asked to find the average speed of a car driving along a main road. You are given a measuring tape and a stopwatch (a) Describe clearly your procedure and what measurements you would take. Use the tape to measure out a reasonably large distance (e.g. 100m). Use the stopwatch to measure the time the car takes to cover that distance. (b) A driver notices you with your stopwatch and brakes slightly. What effect will this have on the average speed? the average speed will be reduced Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
16. A car travels 52 metres in 4 seconds. Calculate the average speed on the car in metres per second. Average speed = distance time 52 = 4 = 13 m/s Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
17. A trolley moves a distance of 10 metres in 2.5 seconds. What is the average speed of the trolley? Average speed = distance time 10 = 2.5 = 4.0 m/s Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
18. A girl on a train measures the time for the train to pass two stations as 2 minutes and 30 seconds. From a map, she finds that the stations are 6 kilometres apart. Calculate the average speed of the train between the two stations. Average speed = distance time 6000 = 150 = 40 m/s Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
19. A student takes five minutes to walk from the playground to his class which is 200 m away. What is his average speed?. Average speed = distance time 200 = 300 = m/s Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
20. Do police radar guns measure average or instantaneous speeds? Why? They measure instantaneous speed. This is because the time taken for the measurement is very short. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
21. How can you tell that the speedometer in a car is measuring the instantaneous speed of the car? The reading changes all the time as the car speeds up and slows down. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
22. How can you measure the instantaneous speed of a toy car at the bottom of a track? (a) Describe what equipment you need, what measurements are needed and how you calculate the instantaneous speed. You need a light gate, an electronic timer and a card on the toy car. Allow the toy car to run down the track and break the beam with the card. Measure the time taken to break the light beam. Measure the length of the card on the car. Divide the length of the card by the time on the timer. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
22. How can you measure the instantaneous speed of a toy car at the bottom of a track? (b) Describe the main differences in measuring the instantaneous speed and average speed of the car. Very short times and distances are used to measure the instantaneous speed. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
23. David measures the time taken for a mask on a trolley to pass through a light gate as 0.6 seconds. The length of the trolley is 15 centimetres. (a) What is the speed? speed = length of card time on timer = 0.15 0.6 = 0.25 m/s (b) State whether David has measured the average speed or the instantaneous speed of the trolley. He has found the instantaneous speed (because it has been found over a very short time). Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
24. Describe what is meant by the term acceleration. acceleration means how much the speed changes each second. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
25. Explain if it is possible for a bicycle have a greater acceleration away from lights than a car? It is possible (briefly). The smaller mass of the bike could allow the cyclist to make it speed up at a quicker rate than the car for the first second or two. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
26. Car performance figures for "Feline Cars Ltd" are shown in the table. (a) Which model has the greatest acceleration? the Cheetah (b) After 5 seconds, approximately how fast will the Leopard be travelling? approx 50 mph (c) The top speed of the Cheetah is 180 mph. At maximum acceleration, what time will it take to reach this speed? 16 to 17 seconds Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
27. A football player is practising taking penalty kicks. Explain why the ball travels faster when the player is running when he strikes the ball than when he is standing still. When the player is running, his foot is moving forward faster when it collides with the ball, and so the force on the ball is greater. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
28. In the World Cup competition in France in 1998, a lighter ball was introduced. Explain why this ball travelled faster than the older ball even though it was kicked exactly the same way. In a collision, the change in speed is greater when the mass is smaller. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
29. In a schools competition, called "Braking Without Breaking" competitors have to find a way of dropping an egg from the ceiling to the floor without breaking the egg. Devise a possible solution. Explain your solution. To avoid breaking the egg, you need to stop it with as small a force as possible. This means it has to be stopped in as big a distance as possible; for example, by dropping it into a thick pile of cotton wool/tissue paper etc. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
30. John's father is a bricklayer. When John was watching his father at work, he noticed that his father's hand moved backwards when he caught a brick thrown to him by his workmate. John remembered that when his father caught the ball when playing table tennis, his hand did not move backwards. Explain this difference. The table tennis ball has a small mass and its speed is changed easily in a short distance. The brick has a much larger mass and its speed is more difficult to change, needing a bigger distance. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
31. Why are golf balls made to be so hard and clubs made of iron or hard wood? The hard surfaces ensure that more of the energy of the club is transferred to the ball during the collision; making it go as fast as possible. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
32. Padder Tennis is a popular indoor game using bats and sponge balls. What is the point of using a sponge ball? The soft surfaces ensure that less energy is transferred to the ball - so it goes slowly. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
33. A golf ball is dropped onto a concrete floor and another dropped into a sand tray. Which rebounds higher and why? The one dropped on to the concrete rebounds higher, because the hard concrete absorbs only a little of the ball’s energy. (The soft sand absorbs more of the ball’s energy.) Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
34. Two tennis rackets are securely clamped. One is old and needs restrung as the strings have stretched, the other is new. Tennis balls are dropped onto each from the same height. Explain which will bounce higher and why. The ball dropped on to the new racket (with the tight strings) rebounds higher, because the tighter strings transfer more of the energy back to the ball. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
35. Two pupils want to find out if altering the speed of launch changes the range. The table below shows the results. (a) What conclusion can the students make? The greater the speed of launch, the greater the range. (b) What would the students need to keep constant to make the experiment fair? The angle of launch, the object (mass and shape) being launched. Beath High School - Int 1 Physics

Beath High School - Int 1 Physics
Intermediate 1 Physics Movement End of Questions and Answers Beath High School - Int 1 Physics