Yr 10 Physics Test 2012
Name: ……………………… Marks: 50
In answering the questions you may wish to use the following information
V =f λ d = vt f =1/T or T = 1/f speed of light = 3 x 108 m/s speed of sound = 350 m/s
Where f = frequency
T = period
V = velocity
λ= wavelength
d = distance
Circle the correct answer
1. It is recognised that there are two basic types of wave motion, transverse and longitudinal. These two types of waves:
A are different because of the ways that they are transmitted through substances.
B travel at the same speed through all substances.
C are basically the same, but one type has greater wavelengths than the other.
D can travel through all types of substances.
2. If a particular ultrasound has a frequency of 25 000 hertz and travels at the velocity or speed of 330 metres per second, then the wavelength of the ultrasound would be closest to:
A 0.1 metres.
B 0.1 metres per second.
C approximately 76 metres.
D 0.01 metres.
3. The different electromagnetic waves are given different names to identify their respective places in the electromagnetic spectrum. These names are chosen based on:
A the different speeds at which they travel in different substances.
B the wavelengths of the particular electromagnetic radiation band.
C the amplitudes of the particular electromagnetic radiation.
Or D the source of the particular electromagnetic radiation.
4. A large wave motion on water is estimated to have a wavelength of 4.0 metres, an amplitude of 3.0 metres and a frequency of 0.1 hertz. This means that the velocity of the wave motion would be:
A 0.4 metres per second.
B 12.0 metres per second.
C 0.3 metres per second.
D 1.3 metres per second.
Questions 5-8 refer to the following information.
An observer in a boat watches waves passing by. She follows the movement of a particular crest and notices that it appears to move to the right by approximately 0.5 metres every second.
5 What she is really observing is:
A the wavelength of the wave motion.
B the velocity of the wave motion.
C the amplitude of the wave motion.
D both the amplitude and the wave length of the motion.
6 The observer in question 6 also notices that two waves pass by her in each
1.0 second period. Another way of
saying this is that the wave motion:
A has a frequency of 4.0 waves per second (Hertz).
B has a frequency of 2.0 Hertz.
C has a velocity of 2.0 metres per second (ms–1).
D has a velocity of 4.0 metres per second.
7 The wavelength of the motion is:
A 0.5 metres.
B 0.5 metres per second.
C 0.25 metres.
D 0.25 metres per second.
8 As the waves pass and the water becomes calm, she estimates that the height from the calm water to a crest would have been 0.1 metre. This measurement represents:
A half of the amplitude of the wave motion.
B twice the amplitude of the wave motion.
C the amplitude of the wave motion.
D one quarter of the amplitude of the wave motion, since there were two waves every second.
9. Which of the following types of waves cannot be generated by the synchrotron:
A Microwaves
B infra-red radiation
C Ultra-violet radiation
D X-rays
PART B Answer all questions in the spaces provided. Marks will be deducted for untidy or illegible work.
1: Complete the table below to show the nature and properties of different types of wave:
Example of wave / Transverse or Longitudinal / Direction of vibration of wave / Can the wave travel through a vacuum? Yes/No / Approximate speed of waveVisible light / T / T / Y / 3 x 108 m/s
Sound / L / L / N / 320m/s
x-rays / T / T / Y / 3 x 108 m/s
(3 marks)
2. Explain what happens to a sound wave as it passes into the following media/situations:
Sound passes from a gas into a liquid.
What happens? the the wave speed increases______
Why does this happen?particles are more densely packed allowing faster transmission of vibrations
(2 marks)
Sound passes into a vacuum.
What happens? sound ceases to be heard
Why does this happen?_no particles to transmit the vibrations______
______
(2 marks)
3. Assuming the speed of sound is 340m/s , what is:
a) The wavelength of lowest note produced by a singer with a frequency of 85Hz?
V =f 340 = 85l, l = 340/85 =4m
(2 marks
b) The period of a note produced by a loudspeaker with the frequency of 800Hz?
T = 1/f = 1/800 = 0.00125s
(2 marks)
4. Look carefully at the waveform shown below. It shows how the amplitude of a wave changes with time. Answer the questions that follow:
a) How many complete periods are shown on this graph? .6......
(1 mark)
b) If each square along the horizontal scale of the graph is equivalent to 1 ms, over how long was this
graph recorded? 10ms......
(1 mark)
(c) How long was one period? 10ms/6 = 1.67ms = 0.00167s
(1 mark)
(d) What is the frequency of this sound? = f = 1/T = 1/0.00167 = 600Hz
(2 marks)
5. Two students standing 2.0 metres apart create a standing wave in a slinky as shown in the diagram below. They create it by one student keeping her end of the slinky still and the other student moves his hand back and forth at a rate of 2 times per second.
a) What would be the name of this harmonic?fundamental......
(1 mark)
b) What is the wavelength of this harmonic? 4m......
(1 mark)
c) What is the frequency of this harmonic? 2Hz......
(1 mark)
d) What speed must the vibration be travelling along the slinky in order to create this wave?
V =fl = 2 x 4 = 8m/s
(1 mark)
e) Now the students create another harmonic by moving the end of the spring back and forth six times per second. In the space below, draw the standing wave that they produce. Label all of the nodes and the antinodes.
(3 marks)
6. a) Describe what happens in each of the of the following parts of the Synchrotron
(i) The Linac -–accelerates electrons that have left the filament from 53% c to 99.99c using very high voltage
(ii)The Booster ring: used to increase energy of the electrons using electromagnets
(iii)The storage ring: electrons are circulate using electromagnets to steer their path and replace any lost energy
(3 marks)
b) Describe three applications of the synchroton: see book p133
(3 marks)
7. (a) In the space below, describe how you could determine what factors affect the strength of an electromagnet. Draw a labeled diagram to help with your explanation
Mention of any four below
Investigate the length of wire, number of coils, diameter of coils, spacing of coils, effect of different cores: copper, iron, brass, aluminium, wood, plastic, current through wire
(2 marks)
(b) State two ways in which you could increase the strength of an electromagnet
Increase circuit current, increase number of coils
(2 marks)
8. Andrew and Rocco are standing on the edge of a canyon. They find that when they yell they hear an echo back. Just for fun they decide to measure how long it takes for the echo to return. Rocco yells “Go Blues” and Andrew measures that the echo takes 1.5 seconds to return. Andrew then sits down and does a calculation and states that the canyon is 233m wide. Rocco says Andrew you are almost right but not quite the canyon is only 167m wide. Who is correct? Support your answer using a relevant calculation.
(round trip)Distance = speed x time = ~(300-340) x 1.5 = 450 - 510m, hence distance each way = 225 – 255m. Andrew’s answer is in this range of acceptable values, Rocca’s is not.
(3 marks)
The following is a picture of a synchrotron
Clearly shown using labels each of the following features see p 133
Booster Ring
Storage Ring
Beamline
Experimental Station
Linac
(5 marks)
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