P1 homework P1d Light and lasers
How did the ancient Greeks send messages to one another? (1)
State five ways that messages are sent to one another today. (2)
Define the term ‘laser’. Describe its properties. (3)
Name six uses of a laser. (3)
What is Morse code? Write the word ‘Physics’ in Morse. (2)
Explain whether Morse code is an analogue or digital signal. (1)
What are the disadvantages of sending signals by light? (2)
What are the advantages of sending a signal using a radio wave? (3)
Define a monochromatic coherent beam. (1)
Draw two waves that are out of phase and two waves that are in phase. What does this mean? (2)
Explain how a compact disc works. Include why a laser is used instead of red light. (6)
Explain how light can become trapped within a transparent object. (6)
Draw a ray diagram illustrating how a fibre optic is used to transmit a light signal. (4)
What happens to light when it meets the boundary with air in an optical fibre? (2)
Using Total Internal Reflection in your answer explain how a small fish in the sea can see large fish behind it. Draw a diagram to help. (6)
Explain how a scientist could deduce the critical angle for a piece of glass. (3)
Describe two reasons why light or lasers are used to send information down optical fibres. (4)
If light with an angle of incidence larger than the critical angle is passed through a glass block, what happens when it reaches the air boundary? (2)
What does an endoscope do? What can a doctor use it for? (2)
Draw a ray diagram explaining how a fibre optic works. Ensure you include why the outer fibres need not be arranged in the same pattern at both ends but the inner fibres do. (6)
60 marks