Science Prelim Practice 3 Answer Key

42a) Note : Vertical axis (Height to which ball bounced (cm)
Horizontal Axis (Height from which ball was dropped (cm)

b) As the height from which the tennis ball was dropped increases, the distance the ball bounced increased.


43a) P - C, Q - D

b) No, they will not be affected by the chemicals. The flow of river water is downwards towards the two factories. OR

Factory A and C are down by the river, so they will not get the polluted water.



44.

A - Blue - There is no change in the amount of carbon dioxide. OR NO respiration / No photosynthesis -> hence no carbon dioxide is produced.

B - Blue - The plants carries out photosynthesis and give out oxygen.

C -Yellow - The fish carries out respiration and produces carbon dioxide.

D - Blue - The plant uses carbon dioxide given by the fish to carry out photosynthesis.


45. b) He must move the torchlight nearer to / further from the pencil and measure the length of the shadow at teach interval.
Compare the results at each interval and determine if the hypothesis is correct or not.

46. a) Electrical energy --> kinetic energy --> sound energy.

b) No, it is a non-magnetic material.