```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.
2
(b)
By how much will the speed of the submarine have increased 5
seconds after the captain looked at his monitor?
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
2
(b)
Smith’s watch?
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?
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
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