An answer key for the ZIMSEC Ordinary Level Physics (4023/1) Specimen Paper
multiple-choice questions is provided below:
Answer Key
Question Correct
Option
Topic / Explanation
1
C
The SI unit of temperature is Kelvin (K).
2
B
Magnitude $= \sqrt{6^2 + 8^2} = \sqrt{100} = 10\text{ N}$.
3
D
Acceleration is highest where the gradient of the $v-t$ graph is
steepest.
4
A
At terminal velocity, weight equals air resistance, so net force and
acceleration are zero.
5
D
Air resistance increases non-linearly with speed, causing
acceleration to decrease non-uniformly.
6
C
Transitions between high and low-pressure systems signal shifts
in weather patterns.
7
B
Increasing the perpendicular distance from the pivot produces a
greater turning effect (torque).
8
A
Momentum $= m \times v = 60\text{ kg} \times 5\text{ m/s} =
300\text{ kg\,m\,s}^{-1}$.
9
A
Gaining height increases gravitational PE; accelerating increases
KE.
10
C
$20,000\text{ g} = 20\text{ kg}$. Work Done $= mgh = 20\text{
kg} \times 10\text{ m/s}^2 \times 10\text{ m} = 2,000\text{ J}$.
11
B
Lubricants reduce friction, diminishing wasted thermal energy
and elevating efficiency.
12
B
A single moveable pulley features a theoretical mechanical
advantage of 2.
13
A
Gluing (solvent welding or specialized adhesives) is appropriate
for bonding plastics.
14
D
Triangles are rigid structures that do not deform easily under load
stresses.
15
A
Brass is on the outside of the curve, meaning it expands more
than iron upon heating.
16
B
Shiny, silvered surfaces are poor emitters and excellent reflectors
of infrared radiation.
17
B
Boyle's Law states $P \propto \frac{1}{V}$, creating a straightline graph through the origin for $P$ vs $\frac{1}{V}$.
18
C
Multiple cylinders enhance physical performance dynamics but
do not dictate computer presence.
19
D
Better engine design translates chemical energy to work with less
waste, yielding higher fuel economy.
20
B
Time period $T = 2.0\text{ s}$. Frequency $f = \frac{1}{T} =
\frac{1}{2.0} = 0.50\text{ Hz}$.
21
D
The sound travels to the seabed and back (total distance $= 2d$),
so $\text{speed} = \frac{2d}{t}$.
22
B
Light rays bending as they exit water into air create a shallow
virtual image due to refraction.
23
A
Electrical power is given by the product of potential difference
and current ($P = VI$).
24
C
Top branch $= 4\,\Omega$ in parallel with bottom $2\,\Omega
\implies 1.33\,\Omega$. Total $= 1.33\,\Omega + 2\,\Omega =
3.33\,\Omega$.
25
C
$t = \frac{Q}{I} = \frac{10\text{ C}}{2\text{ A}} = 5.0\text{
s}$.
26
C
$R = \frac{V}{I} = \frac{12\text{ V}}{4\text{ A}} =
3.0\,\Omega$.
27
C
Iron is a ferromagnetic material and is strongly attracted to
permanent magnetic fields.
28
D
Electromagnets generate a magnetic force to attract a mechanical
armature, flipping switches.
29
B
Shrinking the loop surface area lowers the total magnetic flux
linkage and decreases generated EMF.
30
D
Stepping up voltage drops current, reducing heat loss ($I^2R$)
across long-distance lines.
31
B
Commutators reverse loop current direction every half-turn to
maintain unidirectional rotation.
32
C
Escaping electrons absorb thermal energy to break free as moving
particles with kinetic energy.
33
C
Moving toward Y elongates the tapped wire section, increasing
resistance and its shared voltage drop.
34
A
The top diode is forward-biased (Y turns ON); the bottom diode
is reverse-biased (Z stays OFF).
35
A
Actuators are mechanical output devices that transform input
energy into physical movement.
36
C
Continuous operational uptime is a manufacturing advantage, not
a drawback.
37
C
Control systems function as the robot's brain, processing logic
and running program code.
38
A
In neutral atoms, the number of electrons matches the atomic
proton number (bottom subscript $= 11$).
39
D
Isotopes share the same lower proton number (92) but have
varying mass numbers ($238$).
40
B
$6\text{ years} = 3\text{ half-lives}$. Remaining mass $=
100\text{ g} \times (\frac{1}{2})^3 = 12.5\text{ g}$.
If you would like to prepare further, tell me if you want to focus on:



Formulas and calculations for electricity or mechanics questions.
Comprehensive circuit analysis rules for parallel and series structures.
A breakdown of logic systems and robotics topics.