Answers to Exam-style questions
1 Kinematics – describing motion
1 a Distance in a (particular) direction
b When athlete returns to his original
position/the start
(direct) distance from original
position is zero.
2
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boy
s / m 40
38
3635
4 a Vector quantities have direction and
scalar quantities do not.
One example of a vector, e.g. velocity,
acceleration, displacement, force
One example of a scalar, e.g. speed,
time, mass, pressure
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100 km h–1
girl
30
25
N
20
15
10
500 km h–1
resultant
5
0
0
1
2
3
4
5
6
7
8
9 10 11 12
t/s
a straight line from t = 0, s = 0 to
t = 12, s = 36
b straight line from t = 0, s = 0 to t = 5,
s = 10
straight line from t = 5, s = 10 to t = 12,
s = 38
c 10 s
3 a Each second it travels a constant distance
At least two examples: 108 − 84 = 24 cm,
84 − 60 = 24 cm, 60 − 36 = 24 cm
b speed = d = 24
t 0.1
speed = 240 cm s−1
c 108 + 2 × 24
156 cm
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b Correct vectors drawn and labelled
Scale stated and diagram of sufficient size
Resultant velocity 510 (±5) km h−1
11° W of N or a bearing of 349° (±3°)
c 0.25 × 510 = 128 ≈ 130 km 11° W of N
5 a
velocity of aircraft
B
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7.5 m s–1
15 m s–1
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A
Correct vector diagram
Velocity of aircraft in still air in easterly
direction or calculation
b tout = 5000 = 333 s and treturn = 5000
15
13.5
= 370 s
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total time = 703 or 704 s or 703.7 s
average speed = 10000 = 14.2 m s−1
703.7
AS and A Level Physics © Cambridge University Press
Chapter 1: Answers to exam-style questions
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