A acceleration B mass C momentum D velocity
Answer
1-B
because mass has magnitude only
2 The unit of work, the joule, may be defined as the work done when the point of application of a force of 1 newton is moved a distance of 1 metre in the direction of the force. Express the joule in terms of the base units of mass, length and time, the kg, m and s.
A kg m–1 s2 B kg m2 s–2 C kg m2 s–1 D kg s–2
Answer
2-B
Work done = Force*distance
kgms^-2 *m = kgm^2 s^-2
3 Two forces, each of 10 N, act at a point P as shown in the diagram. The angle between the directions of the forces is 120°.
3-B
Using cosine rule: c^2 = a^2 + b^2 +2abcosC
c^2 = 10^2 + 10^2 +2(100)cos 120
C = 10 N
4 Which experimental technique reduces the systematic error of the quantity being investigated?
A adjusting an ammeter to remove its zero error before measuring a current
B measuring several internodal distances on a standing wave to find the mean internodal distance
C measuring the diameter of a wire repeatedly and calculating the average
D timing a large number of oscillations to find a period
4-A
Basic concept that a systematic error can be reduced by checking for zero error.
5 A student makes measurements from which she calculates the speed of sound as 327.66 m s–1. She estimates that her result is accurate to ±3 %.
Which of the following gives her result expressed to the appropriate number of significant figures?
A 327.7 m s–1 B 328 m s–1 C 330 m s–1 D 300 m s
5-C
because 3% of 330 = 10 m/s
and speed of sound = 330 m/s
6 A steel rule can be read to the nearest millimetre. It is used to measure the length of a bar whose true length is 895 mm. Repeated measurements give the following readings.
6-B
Accuracy: closeness of the measured values to the true value
Precision: closeness of measured values.
7 A projectile is fired at an angle α to the horizontal at a speed u, as shown.
7-C
For vertical component: v = u +at
v = usina - gt
and in horizontal component v = u cos a
8-C
In the first 1/3 of the graph, velocity is increasing hence the gradient should be increasing steeply.
In the second 1/3 of the graph, velocity is constant so gradient should be constant, hence a straight line.
In the last 1/3rd of the graph, gradient is decreasing hence line should be least steep.
Areas X and Y are equal. This is because
A the ball’s acceleration is the same during its upward and downward motion.
B the speed at which the ball leaves the surface after an impact is equal to the speed at which it returns to the surface for the next impact.
C for one impact, the speed at which the ball hits the surface equals the speed at which it leaves the surface
.
D the ball rises and falls through the same distance between impacts.
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