Waves properties

Question 1

Oscillations

Answer 1

The repeated and regular fluctuations above and below the same position

Question 2

Longitudinal waves

Answer 2

the vibrations are parallel to the direction of wave travel.

Question 3

Transverse waves

Answer 3

the vibrations are perpendicular to the direction of the wave travel

Question 4

Mechanical wave

Answer 4

cause oscillations of particles in a solid, liquid or gas and must have a medium to travel through

Question 5

medium

Answer 5

a material which a wave can be transmitted through

Question 6

Electromagnetic waves

Answer 6

cause oscillations in electrical and magnetic fields

Question 7

Rest position

Answer 7

the undisturbed position of particles or fields when they are not vibrating

Question 8

displacement

Answer 8

the distance that a certain point in the medium has moved from its rest position

Question 9

peak

Answer 9

the highest point above the rest position

Question 10

trough

Answer 10

the lowest point below the rest position

Question 11

amplitude

Answer 11

the maximum displacement of a point of a wave from it’s rest position

Question 12

wavelength

Answer 12

distance covered by a full cycle of the wave, usually measured from peak to peak or trough to trough

Question 13

time peroid

Answer 13

the time taken for a full cycle of the wave usually measured from peak to peak or trough to trough

Question 14

frequency

Answer 14

the number of waves passing a point each second

Question 15

how does sound reach our ear

Answer 15

when sound is created the air particles vibrate and collide with each other, causing the vibrations to pass between air particles. The vibrating particles pass the sound through to a person’s ear and vibrate the ear drum.

Question 16

Measuring waves in a ripple tank blurt dis practical rn u *****

Answer 16

1. Set up the ripple tank as shown in the diagram with about 5 cm depth of water.
2. Adjust the height of the wooden rod so that it just touches the surface of the water.
3. Switch on the lamp and motor and adjust until low frequency waves can be clearly observed.

4.Measure the length of a number of waves then divide by the number of waves to record wavelength. It may be more practical to take a photograph of the card with the ruler and take measurements from the still picture.

5. Count the number of waves passing a point in ten seconds then divide by ten to record frequency.

6.Calculate the speed of the waves using: wave speed = frequency × wavelength.

Question 17

hazard consequence and control measures of measuring waves practical in a ripple tank

Answer 17

hazard: Electrical components near water

Shock and damadge to components

Secure electrical components before adding water taking care not to splash

Question 18

Required practical - measuring waves in a solid

Answer 18

1. Attach a string or cord to a vibration generator and use a 200 gram (g) hanging mass and pulley to pull the string taut as shown in the diagram. Place a wooden bridge under the string near the pulley.
2. Switch on the vibration generator and adjust the wooden bridge until stationary waves can be clearly observed.
3. Measure the length of as many half wavelengths (loops) as possible, divide by the number of half wavelengths (loops). This is half the wavelength, doubling this gives the wavelength.
4. The frequency is the
   frequency of the power supply.
5. Calculate the speed of the waves using: wave speed = frequency × wavelength.

Question 19

Hazard consequence and control measures of Required practical - measuring waves in a solid

Answer 19

Cord snapping

damage to eyes

eye protection goggles