waves

explain why the image seen is vitrual

its formed ny imaginary rays crossing

describe a method that could be used ot determine the speed of sound in the air

clap your hands in order to make sounds

measure the distance between the sound sources and detector

use a metre ruler to measure

use a timer to time when the sound made and stop the timing when the sound heard

use measuring instrument such as oscliloscope

divde time by 2 for echo method

use equation speed = distance / time

when a sound wave moves from air into water its wavelength _____

decreases

describe a method the sutdent could used to obtain the result of how the angle of refraction varied with the angle of incidence

place a glass block on a peice of paper

draw around the glass block

use the ray box to shine a ray of light through the glass block

mark the ray of light entering the glass block

mark the ray of light emerging from the glass block

join the points to show the path of the complete ray through the block

and draw a normal line at 90 degrees to the surface

use a protractor to measure the angle of incidence

use a protractor to measure the angle of refraction

use a ray box to shine a ray of light at a range of different angles (of

incidence)

increase the angle of incidence in 10 degree intervals

from an angle

Explain two ways that Method A is better than Method B.

the protractor drawn on the paper means you do not have to movve the mirror

so more likely to record the correct angle of indicidence or reflection

ray in method A does not diverge

making it easier to judge the centre of the ray

what is distance X called

focal point

give one similarly and one difference bewteen the image formed by the convex lens and the image formed by the concave lens

similarity - both are diminished

difference - concave is virtual and convex is real

magnification formula

magnification = image / actual