IGCSE Physics 0625 — Topic 3: Waves

Question 1

Which of the following correctly describes a transverse wave?

AParticles vibrate parallel to the direction of energy transfer BParticles vibrate perpendicular to the direction of energy transfer CParticles move along with the wave from source to receiver DParticles vibrate in circles around their rest position

Question 2

A wave has a frequency of 500 Hz and a wavelength of 0.68 m. What is the speed of this wave?

A735 m/s B0.00136 m/s C340 m/s D250 m/s

Question 3

In a ripple tank experiment, straight water waves pass through a narrow gap. The waves spread out on the other side of the gap. This effect is called:

AReflection BRefraction CInterference DDiffraction

Question 4

A student measures 5 complete waves in a ripple tank and finds the total length is 20 cm. What is the wavelength?

A100 cm B4.0 cm C0.25 cm D25 cm

Question 5

When water waves move from deep water to shallow water in a ripple tank, what happens?

ASpeed increases and wavelength increases BSpeed decreases and wavelength decreases CSpeed decreases and wavelength increases DFrequency changes but speed stays the same

Question 6

Which of these is NOT a property of all waves?

AThey can be reflected BThey can be refracted CThey can be diffracted DThey require a medium to travel through

Question 7

A wave has a speed of 1500 m/s and a frequency of 75 000 Hz. What is the wavelength of this wave?

A0.02 m B50 m C0.05 m D20 m

Question 8

On a displacement–distance graph of a transverse wave, the amplitude is measured as:

AThe distance from crest to trough BThe maximum displacement from the rest position CThe distance between two consecutive crests DThe total height of the wave multiplied by frequency

Question 9

Waves hitting a straight barrier in a ripple tank bounce off at the same angle. The angle of incidence equals the angle of reflection. This is the law of:

ADiffraction BRefraction CReflection DSuperposition

Question 10

A wave has a period of 0.004 s. What is its frequency?

A25 Hz B2500 Hz C250 Hz D0.004 Hz

Question 11

A ray of light strikes a plane mirror at an angle of 35° to the mirror surface. What is the angle of reflection?

A35° B55° C70° D45°

Question 12

A ray of light passes from air into a glass block. The angle of incidence in air is 45° and the angle of refraction in glass is 28°. What is the refractive index of the glass?

A0.63 B1.50 C1.61 D0.89

Question 13

Total internal reflection can occur when light travels from:

AAir into glass BAir into water CGlass into air DA vacuum into glass

Question 14

The critical angle for a type of glass is 42°. What is the refractive index of this glass?

A0.67 B1.00 C1.49 D0.74

Question 15

Which diagram correctly shows a converging lens forming a real, inverted, diminished image?

AObject between F and the lens, image on the same side as the object BObject at 2F, image at 2F on the other side, same size CObject beyond 2F, image between F and 2F on the other side DObject at F, image at infinity

Question 16

Optical fibres used in Indian telecom networks rely on which property of light?

ADiffraction BDispersion CTotal internal reflection DInterference

Question 17

White light passes through a glass prism and separates into a spectrum. This effect is called:

ATotal internal reflection BDiffraction CRefraction DDispersion

Question 18

A converging lens has a focal length of 10 cm. An object is placed 30 cm from the lens. The image will be:

AVirtual, upright, and magnified BReal, inverted, and diminished CReal, inverted, and magnified DReal, inverted, and same size as object

Question 19

A ray of light hits the boundary between glass (n = 1.5) and air at an angle of 30° to the normal inside the glass. What happens to the ray?

AIt is totally internally reflected BIt refracts away from the normal as it enters air CIt refracts towards the normal as it enters air DIt continues in a straight line without bending

Question 20

A diverging lens always produces an image that is:

AReal, inverted, and diminished BReal, upright, and magnified CVirtual, upright, and diminished DVirtual, inverted, and magnified

Question 21

Which of the following lists the electromagnetic spectrum in order of increasing frequency?

ARadio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma rays BGamma rays, X-rays, ultraviolet, visible light, infrared, microwaves, radio waves CRadio waves, infrared, microwaves, visible light, X-rays, ultraviolet, gamma rays DVisible light, ultraviolet, infrared, radio waves, microwaves, X-rays, gamma rays

Question 22

Which type of electromagnetic radiation is used in TV remote controls in Indian homes?

AUltraviolet BMicrowaves CInfrared DRadio waves

Question 23

Which type of electromagnetic radiation can cause skin cancer with prolonged exposure?

ARadio waves BInfrared CVisible light DUltraviolet

Question 24

Satellites in geostationary orbit above Earth are used for communication. Which type of electromagnetic wave is mainly used for satellite TV signals?

AGamma rays BInfrared CMicrowaves DUltraviolet

Question 25

A digital signal has what key advantage over an analogue signal?

AIt can carry more energy BIt uses less bandwidth CIt can be regenerated without losing quality DIt travels faster through optical fibres

Question 26

Which electromagnetic wave has the longest wavelength?

AGamma rays BX-rays CVisible light DRadio waves

Question 27

X-rays are used in hospitals to produce images of bones. Why can X-rays pass through soft tissue but not through bone?

AX-rays are reflected by bones BBone is denser and absorbs more X-rays than soft tissue CSoft tissue emits X-rays DX-rays are diffracted around bones

Question 28

A microwave oven heats food because:

AMicrowaves cause the metal walls to heat up BMicrowaves are absorbed by fat and water molecules in food, increasing their kinetic energy CMicrowaves reflect off the food and create friction DMicrowaves cause nuclear reactions in the food

Question 29

All electromagnetic waves share which property?

AThey all require a medium to travel BThey all travel at the same speed in a vacuum CThey all have the same wavelength DThey all have the same frequency

Question 30

Gamma rays are used in medicine to:

ATake X-ray photographs of broken bones BSterilise surgical instruments and treat cancer CTransmit TV signals DCook food quickly

Question 31

Sound waves are:

ATransverse waves that need a medium BLongitudinal waves that need a medium CTransverse waves that can travel through a vacuum DLongitudinal waves that can travel through a vacuum

Question 32

A student stands 170 m from a large wall and claps. She hears the echo 1.0 s later. What is the speed of sound?

A170 m/s B340 m/s C85 m/s D680 m/s

Question 33

A sitar string vibrates at a higher frequency. What happens to the sound produced?

AThe sound becomes louder BThe pitch increases CThe sound travels faster DThe wavelength increases

Question 34

Sound cannot travel through:

ASteel BWater CAir DA vacuum

Question 35

Ultrasound is sound with a frequency:

ABelow 20 Hz BBetween 20 Hz and 20 000 Hz CAbove 20 000 Hz DExactly 20 000 Hz

Question 36

A ship sends an ultrasound pulse straight down to the sea floor. The pulse returns after 0.8 s. The speed of sound in seawater is 1500 m/s. How deep is the sea at this point?

A1200 m B600 m C300 m D2400 m

Question 37

Which change would make a drum produce a louder sound?

AUse a thinner drum skin BHit the drum harder CUse a smaller drum DTighten the drum skin more

Question 38

During Diwali celebrations in Bangalore, Tara notices she sees the flash of a distant firework before she hears the bang. Why?

ALight needs air to travel but sound does not BSound is produced after the light CLight travels much faster than sound DSound waves are absorbed by the air completely

Question 39

A compression in a sound wave is a region where:

AAir particles are spread far apart BAir particles are pushed close together CThere are no air particles DAir particles are moving perpendicular to the wave direction

Question 40

The speed of sound is fastest in:

AAir at 20 °C BWater at 20 °C CA vacuum DSteel at 20 °C

Paper 2 — Multiple Choice

Section A: General Properties of Waves (3.1)

Section B: Light (3.2)

Section C: Electromagnetic Spectrum (3.3)

Section D: Sound (3.4)