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Grade 8 · Physics

Grade 8 Physics diagnostic

12 questions on motion & graphs, forces & equilibrium, energy, work & power, pressure & fluids, waves & sound and electricity & circuits. Answer what you can, then check your answers to see which topics are secure and what to practise next.

12 questions6 topicsAbout 15 minutesSet 1 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 rover travels 112 m in 64 s, then 136 m in 66 s. Find its average speed for both stages. Round to 3 decimal places if needed. Answer in m/s.
m/s
2Motion & graphsA robot moves 42 m east and then 10 m west along a straight line. Find the total distance travelled. Round to 3 decimal places if needed. Answer in m.
m
3Forces & equilibriumA mass of 96 kg is in a model gravitational field of 10 N/kg. Find its weight. Round to 3 decimal places if needed. Answer in N.
N
4Forces & equilibriumOn a weightless balanced beam, 29 N acts 7 m left of the pivot. What downward force at 4 m right balances it? Forces are perpendicular to the beam. Round to 3 decimal places if needed. Answer in N.
N
5Energy, work & powerA model device transfers energy at constant power 615 W for 50 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.
J
6Energy, work & powerA 33 kg load is raised vertically by 1 m in a field g = 10 N/kg. Find its gravitational potential-energy gain. Round to 3 decimal places if needed. Answer in J.
J
7Pressure & fluidsA normal force of 349 N acts uniformly over 0.18 m². Find the pressure. Round to 3 decimal places if needed. Answer in Pa.
Pa
8Pressure & fluidsAn object displaces 0.003 m³ of liquid of density 1000 kg/m³ with g = 10 N/kg. Find buoyant force.
N
9Waves & soundAn echo returns after 460 ms. The sound speed in this medium is 340 m/s. Find the distance to the stationary reflector. Round to 3 decimal places if needed. Answer in m.
m
10Waves & sound19 complete oscillations take 27 s. Find the period. Round to 3 decimal places if needed. Answer in s.
s
11Electricity & circuitsAn ohmic resistor of 74 Ω has potential difference 41 V. Find current. This is a paper calculation, not a construction instruction. Round to 3 decimal places if needed. Answer in A.
A
12Electricity & circuitsA model device uses constant power 1850 W for 16 h. Find the energy in kilowatt-hours. Round to 3 decimal places if needed. Answer in kWh.
kWh