Page 16 - 1202 Question Bank Physics Form 4

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CHAPTER 1 22. D When we divide the measured time by 20, the inaccuracy
1
associated with period T due to human reaction will be only 20
of the human reaction time i.e 0.015 to 0.025 s.
Paper 1
23. C The Earth is not a perfect sphere – it’s slightly flattened
1. A Physics is the study of matter and energy as well as phenomena at the poles and bulges out near the equator, so points near
happening around us. the equator are farther from the center of mass. The distance
between the centers of mass of two objects affects the
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2. D Candela (cd) is the base unit for luminous intensity. gravitational force between them, so the force of gravity on an
3. D Thermodynamic temperature is a base quantity. object is smaller at the equator compared to the poles.

4. B S.I. is a worldwide standardisation of measurement units that has 24. C All true except T is directly proportional to l. The correct
2
simplified the work in science, sports, commerce, medicine and relationship is T is directly proportional to l.
other fields.
25. C All true except m is directly proportional to T. The correct
2
5. C Both base and derived quantities may be scalars or vectors. relationship is T is directly proportional to m.
Vector has both magnitude and direction.
26. D A straight line drawn through the maximum number of
6. D 1 N kg = 1 m s , experimental points may not be the best fitted line.
–1
–2
hence 10 000 N kg = 10 000 m s .
–2
–1
7. A All three: velocity, momentum and impulsive force have both Paper 2
magnitude and direction. Section A
8. A All the four quantities do not have direction. 1. (a) Base quantity is physical quantity that cannot be derived from
other physical quantities.
9. D Ampere, pascal, watt and ohm are metric units. (b) (i)
10. A r = m L , Base quantity Derived quantity
–3
hence m = rL . 3
Time Power
11. C All true Temperature Chapter 1
a
12. C The correct equation is p = q + c. (ii)
b Metric system Imperial system
13. C Curve with positive gradient and passing through the origin. watt °F
Answer D shows an inverse-proportionality relationship.
14. A The R line has steeper slope than S. 2. (a) (i) Distance
(ii) Force, charge (any one)
15. A The X line has steeper slope than Y but at p = 0, line Y is above (iii) Force Fr 2
X. (b) Unit for k = Qq
–2
16. A Inverse proportionality: x y = x y , = kg m s × m 2
1 1 2 2 (A s × A s)
2.4 × 25 = 10 × y 2 = kg m s A –2
3
–4
y = 6
2 t + t
π 2
17. C Square both sides, r = ( ) s, if r is plotted against s, the 3. (a) (i) Average time, t = 2 2 1
2
2
ß
π 2
gradient is ( ) . = 22.22 + 22.13
ß
18. B A graph represents the average value of the readings of an = 22.18 s 2
experiment and provides a visual relationship between variables (ii) To reduce the inaccuracy due to human reaction time.
under investigation. (iii) • Set the simple pendulum swings with small amplitude
• Make sure the oscillations are on a vertical plane only.
19. B A line of best fit is a straight line drawn through the maximum 22.18
number of points and balancing about an equal number of points (b) (i) T = 20
above and below the line. = 1.109 s
g
20. A Making an inference means interpreting or explaining factors as (ii) l = ( 4π 2) T 2
a result of an observation for a phenomenon. The ultimate goal ( 981 2
of a problem statement is to transform a generalized problem = 4π 2 ) × (1.109)
into a targeted, well-defined problem; one that can be resolved = 30.56 cm
through scientific research. (iii) The time taken for 20 swings will be much longer
(roughly 2.5 times) because the value of g on the Moon
m
21. A Using y = sx + c, substitute x with V, y with U, s = , and c is surface is 6 times smaller than that on the Earth.
n
U-intercept = m and then rearrange to make V as a subject in the
equation.
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Answer QBank Physics F4.indd 107 10/02/2022 4:03 PM