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Grade 12 · Physics

Grade 12 Physics diagnostic

16 questions on motion & graphs, forces & equilibrium, energy, work & power, momentum & collisions, thermal physics, electricity & circuits and magnetism & induction, plus 2 from Grade 11. Answer what you can, then check your answers to see which topics are secure and what to practise next.

16 questions7 topicsAbout 20 minutesSet 2 of 5

Skip a question if you do not know the answer. It is better than guessing, because it shows what to practise.

1Motion & graphsA cart moves at 23 m/s, then slows at a constant 4 m/s² to rest. Find its braking distance, excluding any reaction distance. Round to 3 decimal places if needed. Answer in m.
m
2Motion & graphsA cart moves along a straight track. Its position is recorded every second: t = 0 s: 1 m; t = 1 s: 3 m; t = 2 s: 7 m; t = 3 s: 13 m; t = 4 s: 21 m. What is its average speed over the 4 seconds?
m/s
3Forces & equilibriumTwo perpendicular forces of 216 N and 405 N act on a point. Find the magnitude of their resultant. Round to 3 decimal places if needed. Answer in N.
N
4Forces & equilibriumA crate on a frictionless surface has two horizontal forces on it: 100 N toward the east and 10 N toward the west. (Vertical forces balance.) What happens to the crate’s motion?
5Energy, work & powerAn ideal linear spring has k = 180 N/m and extension 46 cm. Find the stored elastic energy. Round to 3 decimal places if needed. Answer in J.
J
6Energy, work & powerA constant 19 N force acts through a 24 m displacement. The cosine of the angle between them is 1. Find the work by this force. Round to 3 decimal places if needed. Answer in J.
J
7Momentum & collisionsA 2 kg object has signed velocity -5 m/s on a chosen axis. Find its signed momentum. Round to 3 decimal places if needed. Answer in kg·m/s.
kg·m/s
8Momentum & collisionsMomentum changes by +64 kg·m/s during 50 ms. Find the signed average net force. Round to 3 decimal places if needed. Answer in N.
N
9Thermal physicsMix 8 kg at 29 °C with 2 kg at 65 °C of the same liquid. Assume equal constant specific heat, no phase change, negligible container heat capacity and no losses. Find equilibrium temperature. Round to 3 decimal places if needed. Answer in °C.
°C
10Thermal physicsA 2.6 kg sample with specific heat 900 J/(kg·°C) warms by 38 °C. No phase change or heat loss occurs. Find energy supplied. Round to 3 decimal places if needed. Answer in J.
J
11Electricity & circuitsA theoretical 20 V ideal source supplies parallel ohmic resistors 6 Ω and 3 Ω. Find total source current. Round to 3 decimal places if needed. Answer in A.
A
12Electricity & circuitsIn a theoretical circuit, 35 Ω and 16 Ω are in series across an ideal 37 V source. Find their total electrical power. Round to 3 decimal places if needed. Answer in W.
W
13Magnetism & inductionAn ideal AC transformer has primary 1700 turns, secondary 900 turns and primary voltage 60 V. Find secondary voltage. Paper model only. Round to 3 decimal places if needed. Answer in V.
V
14Magnetism & inductionA 21 cm straight wire carries 3 A perpendicular to a uniform field of 1.4 T. Find magnetic force magnitude. Round to 3 decimal places if needed. Answer in N.
N

From Grade 11

These questions check skills from the grade below, so gaps can be spotted early.

15Forces & equilibrium (Grade 11)On a weightless balanced beam, 110 N acts 1 m left of the pivot. What downward force at 8 m right balances it? Forces are perpendicular to the beam. Round to 3 decimal places if needed. Answer in N.
N
16Electricity & circuits (Grade 11)An ohmic resistor of 74 Ω has potential difference 53 V. Find current. This is a paper calculation, not a construction instruction. Round to 3 decimal places if needed. Answer in A.
A