John Buchan Middle School Science Test Revision 6G Changing Circuits 36 min 37 marks Name John Buchan Middle School 1
Level 3 1. Simple circuit (a) Sue has a cell (battery), some wire and a bulb. She makes a simple circuit. Sue joins these objects into the circuit, to see if the bulb lights: cork iron nail copper rod plastic ruler steel spoon She records her results in this table. Object A B C D E spoon Bulb lights? No Yes Yes No Yes John Buchan Middle School 2
Object B is the steel spoon. Complete the sentences below to say what objects A and C are. (i) Object A is either the...... or the...... (ii) Object C is either the........ or the.... (b) Some of the objects are electrical insulators. Some are electrical conductors. Use the information in Sue s table. Write A, B, C, D and E in the correct group below to sort the objects. Electrical insulators Electrical conductors John Buchan Middle School 3
(c) David makes a circuit with two bulbs and one cell (battery). He draws a picture of it. In the space below, draw a circuit diagram of David s circuit. Use symbols. Level 4 2. Electricity (a) Naomi's torch is not working. The cells (batteries) inside the torch are like this: bulb switch metal strip cell John Buchan Middle School 4
Naomi puts the cells back in a different way and the torch works. Write + and in the correct place in each cell below to show how Naomi puts them back. (b) Inside the torch, a metal strip connects the cells and bulb. Describe ONE property of metal that makes it a good material to connect the cells and bulb. John Buchan Middle School 5
(c) In the space below, draw a circuit diagram of Naomi's torch with the cells put in correctly. Use only the following symbols: cell bulb switch 2 marks John Buchan Middle School 6
3. Bright Lights (a) Jill made circuits with different lengths of wire, the same battery and the same bulb. The wire is coated in plastic. She recorded her results in a table. length of wire (m) 40 30 20 10 1 brightness of light from bulb no light dim glow faint light bright light very bright light Look at the table. Describe how changing the length of the wire in the circuit affects the brightness of the light. 2 marks John Buchan Middle School 7
(b) Sharon had the same kind of wire. She wanted to know how much wire she had on her reel. When the reel of wire was connected into the same circuit there was a faint light from the bulb. Use the information from the table. How much wire was on the reel when there was a faint light from the bulb? Tick ONE box less than 5 m 5 15 m 15 25 m 25 30 m more than 40 m John Buchan Middle School 8
Level 5 4. Train in the tunnel (a) Andrea wants a light bulb to light up when her toy train is pushed through a tunnel. She makes an electric circuit for her toy train. Andrea makes a tunnel and puts a strip of foil inside the tunnel roof. The picture shows Andrea s tunnel and the wiring on her train. position of foil inside the tunnel roof foil foil strip 1 foil strip 2 + tunnel bulb cell (battery) wire The foil strips on the train act like a switch. When both foil strips on the train touch the foil inside the tunnel roof, the bulb lights up. Complete the circuit diagram below by drawing the switch and the bulb to show the circuit on Andrea s train. (ii) (i) 2 marks John Buchan Middle School 9
(b) Give ONE property of metal foil which makes it a good material for Andrea to use as a switch.... (c) When only one foil strip on the train is touching the foil in the tunnel, the bulb does not light up. Complete the sentence to explain why the bulb does not light up. The circuit... (d) The bulb on the train only lights up when all of the train is inside the tunnel. Andrea wants to improve her circuit so the bulb lights up when the train has only just entered the tunnel. Which train has foil strips that would allow the bulb to light when the train has only just entered the tunnel? Tick ONE box. + + + + John Buchan Middle School 10
5. Circuits and sensors (a) Class 6D makes different circuits using the same type of bulbs, motors with fans and cells (batteries). (i) Tick ONE box to show the circuit in which the bulb or bulbs are brightest. circuit 1 circuit 2 circuit 3 circuit 4 (ii) Explain why the circuit you chose has the brightest bulb or bulbs....... John Buchan Middle School 11
(b) Tick ONE box to show which circuit diagram below is correct for circuit 3. M M M 7 (c) Each of the circuits made by class 6D has one cell. Complete the sentence below to explain the effect on the bulbs of adding a second cell to circuit 1. The bulbs will... (d) Class 6D made three new circuits. They used a light sensor to measure the brightness of one of the bulbs in each circuit. The sensor gave the results on the graph below. bright Light sensor reading dim A B C Circuit John Buchan Middle School 12
Write A, B or C next to each circuit below to show which circuit gave each light sensor reading on the graph. circuit... circuit... circuit... 6. The Steady Hand Game (a) Sita has made a game. In her game, she has to move a metal ring along a piece of thick wire until it reaches the rest position. When she is moving it, the metal ring must not touch the wire. If it touches the wire, a bulb will light and a buzzer will make a noise. rest position (Wires and cell hidden inside the box) The metal ring and the thick wire both let electricity through. What is the scientific name for materials that let electricity through? John Buchan Middle School 13
(b) Sita made the rest position by covering the wire with an insulating material. When she puts the metal ring down on the rest position, the bulb and buzzer cannot work. Which materials might Sita have used to insulate the wire for the rest position? Tick the three correct boxes. clear sticky tape copper wire plasticine newspaper steel wool aluminium foil 2 marks (c) The bulb and buzzer will only work in Sita s game when the metal ring touches the wire. Tick ONE box to show which is the correct circuit for her game. John Buchan Middle School 14
(d) To make the electrical circuit for the game, Sita uses a buzzer, a bulb and a cell (battery). Label the symbols below by writing buzzer, bulb or cell.......... (e) Kalinda plays the game. She thinks the buzzer should be louder. How can Sita change her circuit so that the same buzzer makes a louder sound? 7. Bathtime (a) Jack gets out of the bath. He dries himself with a towel. Why is towelling a good material to dry himself with? John Buchan Middle School 15
(b) Small puddles of water drip on to the floor tiles and stay there. Tick ONE box to say why the puddles stay on the floor tiles. The puddles stay on the floor because the floor tiles soak up water. bend easily. are waterproof. are solid. (c) The bathroom window is closed. Jack sees drops of water on the inside of the bathroom window. Name the process that causes the water to appear on the bathroom window. John Buchan Middle School 16
(d) The flow diagram below shows where the water goes before it reaches the window. Complete the flow diagram to show where the water is. water in the bath, in the towel and on the floor tiles water in... water on the window (e) Jack dries his hair with an electric hairdryer. He does not use the hairdryer in the bathroom because it might get wet. Why is it dangerous to use an electric hairdryer near water? John Buchan Middle School 17
8. Circuits (a) Daisy and Rema make this circuit. They close the switch but the electricity does not flow. The bulb does not light. The electrical wires are connected properly. Give TWO possible reasons why their circuit does not work when they close the switch. (i)... (ii)... (b) They make another circuit. It works. They put these objects into the gap in the circuit one at a time: steel scissors plastic comb cardboard strip aluminium spoon copper tube John Buchan Middle School 18
The metal objects let the electricity flow through, and the bulb lights. What is the scientific name for materials that let electricity flow through them? (c) Daisy says: Let's see which metal makes the bulb light most brightly. Rema says: But we cannot compare the metals because we used different shaped objects. Let's use wires instead. They make three similar circuits. First they make their circuit with steel wire, then with copper wire, then with aluminium wire. To compare their results, what must they keep the same about the wire in all three circuits and what must be different? Tick ONE box in each row below. Wire Type of metal Length Thickness Must be the same Must be different John Buchan Middle School 19
(d) The children can change the wire in their circuit to make the bulb brighter. Describe ONE other change that the children could make to their circuit to make this bulb brighter when they close the switch. John Buchan Middle School 20