8/8/2019 Modul Hikmah 15

1/5

HIKMAH MODULE

148

SCIENCE SPM

MODULE 15

PAPER 1

1. Define wave frequency.

A. Displacement in metres between two successive crestsB. Distance traveled by the wave in one secondC. Displacement of the wave from its position of restD. Number of complete oscillations per second

2. A Radio wave has a velocity of 3000 m/s and a frequency of 500 Hz. What is itswavelength?

A. 2m

B. 4mC. 6mD. 8m

3. What is the function of a transformer?

A. To change the size of a direct currentB. To change the resistance in an electric circuitC. To change the chemical energy of a fuel into electrical energyD. To change the voltage of an alternating current

4. Which of the following part of a radio transmitter is incorrectly matched with itsfunction?

A. Aerial : Transmit modulated carrier wavesB. Modulator: Combines audio waves with radio wavesC. Oscillator: Produces carrier radio wavesD. Microphone: Changes electrical signals into sound

5. Which of the following electrical components is used to separate radio waves fromsound waves?

A. DiodeB. InductorC. CapacitorD. Transistor

8/8/2019 Modul Hikmah 15

2/5

HIKMAH MODULE

149

6. In radio broadcasting, what is meant by the term modulation?

A. Changing the amplitude of radio wavesB. Changing the frequency of radio wavesC. Separating audio waves from radio wavesD. Combining audio waves and carrier waves to form modulated waves

7. Figure 3 shows the spectrum of electromagnetic waves.

W Infrared ray X Ultraviolet ray Y ZFigure 3

What are the electromagnetic waves W,X,Yand Zrespectively?

W X Y Z

A. Radio wave Visible light X ray Gamma rayB. Gamma ray X-ray Radio wave Visible

C. Visible light Gamma ray X-ray Radio waveD. X-ray Radio wave Gamma ray Visible light

8. The advantages of satellite communication are thatI. the microwaves are not influenced by weather changes

II. the volume of information transmitted and received can be larger than that ofcables

III. live telecasts can be carried globally and simultaneously

A. I and IIB. I and III

C. II and IIID. I, II and III

9. A sound wave has a frequency of 200Hz and a wavelength of 1.5 m. What is itvelocity?

A. 13.3 m/sB. 30.0 m/sC. 133.3 m/sD. 300.0 m/s

10. Which of the following electrical components is used to separate radio waves fromsound waves?.

A. DiodeB. InductorC. CapacitorD. Transistor

8/8/2019 Modul Hikmah 15

3/5

HIKMAH MODULE

150

PAPER 2SECTION A + B

1. (a) Define wavelength. [1 mark]

______________________________________________________________________

(b) What is the S.I unit used for measuring. [3 marks](i) wavelength

________________________________________________________________

(ii) wave velocity?

________________________________________________________________

(iii) frequency?

________________________________________________________________

(c ) A sound wave has a frequency of 1200Hz and moves with a velocity of 240m/s.What is its wavelength? [1 mark]

(d)What is the use of the ionosphere in radio broadcasting? [1 mark]

______________________________________________________________________

______________________________________________________________________

(e) Why are relay stations required in broadcasting through televisions? [1 mark]_____________________________________________________________________

______________________________________________________________________

2. Diagram shows a diagram of a radio transmitter.

Y

Oscillator

Modulator AmplifierAmplifierX.

8/8/2019 Modul Hikmah 15

4/5

HIKMAH MODULE

151

(a) Name component X in the box provided in diagram [1 mark]

(b) Draw a waveform transmitted by Y in the space below. [1 mark]

(c ) What is the function of the modulator? [1 mark]

______________________________________________________________________

(d) Diagram below shows a symbol of an electronic component.

(e) Name the electronic component represented by the symbol. [1 mark]

______________________________________________________________________

(f) Where is the electronic component in diagram found in the radio transmitter.[1 mark]

______________________________________________________________________

SECTION C

1. (a) Why is communication satellite unable to stay in orbit forever? [2 marks](b) Why are radio waves suitable for use in radio broadcasts? [2 marks](c) State 4 ways by which news was sent in the days before radio and television were

used. [4 marks]

8/8/2019 Modul Hikmah 15

5/5

HIKMAH MODULE

152

MODULE 15 - ANSWERS

PAPER 1

1. D 2. C 3. D 4. D 5. D 6. D 7. A 8. D 9. C 10. A

PAPER 2SECTION A + B

1. a) Wavelength is the distance between two successive crests or troughs in a waveb) i) metre

ii) metre per second m/siii) Hertz/Hz

c) = v/f 240 m/s / 1200Hz + 0.2 md)To reflect radio waves back to earthe) Radio waves used for television broadcasting travel in straight lines through a short

distance

2. a) Microphoneb) i) Aerial

ii)

c) It combines audio signals with radio frequency waves to produce modulated radiowaves which can be transmitted across a long distance

d) i) Transistorii) Amplifier

Section C1. a) Because its electronic components can break down due to time.

The exposure of the electronic components to strong sunlight in outer space will

make the components to malfunction.b) Travel very fast/ speed of light, can travel through vacuum, absorbed slightly by air,

not stopped or scattered by obstaclesc) Pigeons, smoke signals, relay runners, riders or horses.