Page 226 - Physics

Physics for Secondary Schools

(c) they all explain how fast a
certain task is performed.
(d) all are typical examples of
Ball
chemical energy. Ball

(v) A student calculates his power in
running up a fl ight of stairs. He
measures the vertical height of the
stairs, the time taken to run up the
stairs and his weight. How does he
calculate his power? Figure 9.27
()a height time weight 
Ignoring the effects of air resistance,
height weight which statement about the total

()b energy of the ball is correct?
time
(a) It is the same at all points.
time weight

()c (b) It is greatest at point 1.
height
time (c) It is greatest at point 2.
()d
height weight (d) It is greatest at point 3.
(viii) Which one of the following

(vi) The table shows some data from quantities has the same unit?
a high jump competition. Which (a) speed and force.
athlete jumps the highest? (b) work done and energy.

Weight Answer Increase in (c) work done and power.
(N) gravitational (d) potential energy and power.
potential
energy (J) (ix) The diagram shows a small car of
mass 500 kg approaching a hill.
(a) 600 1 320
It moves up the hill with constant
(b) 700 1 610 speed as shown in Figure 9.28.

(c) 800 1 760
(d) 900 1 800 200 m
10 m
(vii) A student is investigating the energy
changes when a ball is dropped from mass 500 kg
a height. The Figure 9.27 illustrates Figure 9.28
the energy changes when a ball is The gravitational fi eld strength g
released at three different positions.
is 10 N/ kg. Ignoring friction, how

220
Student’s Book Form One

Physics Form 1 Final.indd 220 16/10/2024 20:58