Grade 10 First Term Examination (Revision) Physics. 1. A part of travel graph of John's journey from his house to the shops and back is shown below.

Transcription

1 Grade 10 First Term Examination (Revision) Physics SP1 & SP2: Motion & Forces 1. A part of travel graph of John's journey from his house to the shops and back is shown below. a) Find out John's speed for the first 30 minutes of his journey.... John spends 15 minutes at the shops. He then travels back to his house at 60 km/h. (b) Complete the travel graph. (Total 2 marks) 2. A bowling ball rolls for 3 s and hits a pin. The graph shows how the velocity of the ball changes with time. (a) How can the graph be used to find the distance that the ball rolls before it hits the pin?...

2 (b) Calculate the momentum of the ball before it hits the pin... (c) What is the velocity of the ball after it hits the pin?... (ii) After the collision, the ball and the pin have the same velocity. Calculate the mass of the pin.... (Total 4 marks) 3. Some cars have a pedestrian airbag for safety. If a pedestrian is hit and lands on the front of the car, the airbag inflates. Use ideas about momentum to explain how this airbag can reduce injuries to pedestrians.... (2) SP3: Conservation of Energy 4. Some students investigate a model of the craters produced by meteorite impacts. They drop balls into a tray filled with sand. They use six balls with different masses. They drop each ball from the same height. a. (i) Which one of these graphs shows the relationship between the gravitational potential energy (GPE) of the balls and their mass when they are all at the same height? Put a cross (x) in the box next to your answer. (ii) Describe how the energy of a ball changes as it drops towards the sand. (2)...

3 This photograph shows the sand after several balls have hit it The students read this information in a textbook: When work is done, energy is transferred. iii) Explain how work is done when the balls impact on the sand. (2) A lamp has a wire filament that glows white hot when it is in use. (a) A 100 W filament lamp is 15% efficient. (i) Explain the meaning of the term 15% efficient.... (ii) Draw a labeled energy flow diagram to show what happens to 100 J of electrical energy supplied to the lamp. (2) (b) Many people choose to buy expensive low-energy lamps instead of cheaper filament lamps. Give two reasons for this.... (2) (c) When a filament lamp is in use, the temperature of the wire filament remains at 2500 C. Explain why this temperature remains constant. (2) a. Electricity is produced in power stations. A partly-labeled diagram of a coal-fired power station is shown in the below figure. Label the missing parts. (2) b) Describe the differences between a coal-fired power station and a nuclear power station. (2) c) Coal-fired power stations are still in general use. Explain why wind turbines have not replaced them. SP4: Waves 7. (a) The diagram represents water waves travelling from deep water into an area of much shallower water.

4 (i) (ii) State the name of the effect shown in this diagram.... Complete the sentence by putting a cross (x) in the box next to your answer. When the waves go from deep water to shallow water, (iii) Explain another change which can be seen from the diagram when the waves go from deep water to shallow water In 1969 the Apollo astronauts left a laser reflector on the Moon. This was to be used to help scientists to make very accurate measurements of the distance between the Earth and the Moon. The mean distance between the centres of the Earth and Moon is km, and light travels at m/s. a) How long would it take a beam of light to travel between the centers of the Earth and Moon? b) The diameter of the Earth is km and the diameter of the Moon is 3480 km. How long would it be before the reflection of a laser beam fired from Earth was detected on the Earth? (2) 9. Ultrasound can be used in industry for detecting internal cracks in metals. (a) State two features of ultrasound.... (2) (b) The diagram shows an ultrasound transmitter and detector fixed to the front of a metal block. The block has an internal crack. The diagram below shows the screen of the oscilloscope connected to the detector.

5 (i) Explain why pulse A and pulse B occur (2) (ii) The metal block is 120 mm from front to back. What is the distance, from the front of the block to the internal crack? (Total 5 marks) 10 (a) Sound travels through the air as longitudinal waves. Describe how the air particles move when a sound wave passes. (2)... (b) Elephants call to each other using infrasound. People cannot hear these infrasound calls. Which of the following statements is the reason that people cannot hear infrasound? Put a cross (x) in the box next to your answer. A. the amplitude of infrasound is too big B. the frequency of infrasound is too low C. the speed of infrasound is too fast D. the wavelength of infrasound is too short SP5: Light & Electromagnetic Spectrum 11. The photograph shows a refracting telescope. a) Complete the sentence by putting a cross (x) in the box next to your answer. A converging lens refracts light to produce an image of a distant object on a screen. The image on the screen is A magnified B. virtual C. upside down D. the right way up b) More recent telescopes use two converging lenses, as shown in the above photograph. Lens A produces a real image of the planet. Describe the purpose of lens B. (2)...

6 12. i) Herschel discovered invisible rays beyond one end of the visible spectrum. Ritter discovered invisible rays beyond the other end of the visible spectrum. Compare and contrast the two experiments leading to these discoveries. You may draw labeled diagrams to help with your answer. (6) 13. An optical telescope used to observe stars, is to built either at the bottom or at the top of a high mountain. a) What type of electromagnetic radiation is detected by an optical telescope?... b) Give one advantage of having the telescope at the top of the high mountain rather than at the bottom.... c) Gamma radiation from the sun is absorbed by the atmosphere. Where should a telescope designed to detect gamma radiation be positioned? Images of hands can be made using different parts of the electromagnetic spectrum. Both images give information about a hand. (i) Suggest what information the infrared image gives about a hand (2) (ii) Explain why taking an X-ray image of a hand is more dangerous than taking an infrared image. (2) 15. Earthquakes can cause seismic waves in the Earth. P-waves are one type of seismic wave. P-waves are longitudinal. If a P-wave is moving from left to right, how do the particles in the wave move? Put a cross (x) in the box next to your answer. (a) Scientists can use seismometers to detect and record seismic waves from earthquakes. P-waves travel at 5 km/s. During a recent earthquake, a seismometer 120 km away detected the seismic waves. Calculate the time, in seconds, it took before the P-wave reached the seismometer. (2)

7 (ii) Earthquakes also produce S-waves. S-waves travel more slowly than P-waves. Describe how seismometer records of P-waves and S-waves can be used to work out where an earthquake happened. (3) 16) a). The diagram below shows white light shining onto a green filter, followed by a red filter. Label the colour of light which passes through the green filter at point A. b). What colour light, if any, would be seen at point B? Explain your answer..c) What would happen if you shone blue light onto a red filter? Explain your answer.