Rosshall Academy Physics Department Name: Term 3 Week 5 Homework General 1. Shona and Debbie are revising at home for a Physics test. (a) Shona makes up the crossword and clues shown below to test Debbie’s knowledge of the application of physics in medicine. Complete the crossword started by Debbie. (b) 3 Debbie says that lasers are used in medicine and asks Shona to describe one use. Write down one use of lasers in medicine. 1 (c) Shona asks Debbie to draw a diagram showing how a beam of laser light would be bent as it passes through a glass block. She begins by drawing the diagram as shown below. (i) What name is used to describe the bending of the laser light? 1 (ii) Complete the diagram to show the path of the laser beam through and out of the block 1 2. A miniature submarine is travelling horizontally through the water. The captains sees the following information on a monitor in front of him. Mass of submarine = 500 kg Speed of submarine = 2 metres per second Acceleration = 0.1 metres per second per second (a) Calculate the horizontal force which is accelerating the submarine. Space for working and answer 2 (b) By how much will the speed of the submarine have increased 5 seconds after the captain looked at his monitor? Space for working and answer 2 Credit 1. Two timekeepers Smith and Jones are timing a 100 m sprint. Smith starts her stopwatch when she sees the smoke from the starter’s gun. Jones starts his watch when he hears the bang from the gun. Both stop their watches at the instant the winner reaches the finishing line. Both timekeepers are l00m from the starter. (a) Which timekeeper records the shorter time for the winner? Explain your answer. 2 (b) The reading on Jones’ watch is 11.3s.What is the reading on Smith’s watch? Space for working and answer 3 2. A tail and brake lamp on a car has two filaments in the same glass bulb as shown in figure 1. One filament has a resistance of 7 and the other a resistance of 28 . Figure 2 shows the circuit containing the two filaments. (a) What is the resistance of the two filaments when connected in parallel by closing switches X and Y? Space for working and answer 3 (b) For safety reasons, the brake light has a higher power than the tail light. Explain which filament acts as the brake light. 2 General Mark Credit Mark Parent’s signature /10 /10 Grade Grade