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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 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 & graphsOn an east-positive axis, position changes from -47 m to -35 m in 11 s. Find the signed average velocity. Round to 3 decimal places if needed. Answer in m/s.
m/s
2Motion & graphsA rover travels 294 m in 64 s, then 113 m in 15 s. Find its average speed for both stages. Round to 3 decimal places if needed. Answer in m/s.
m/s
3Forces & equilibriumOn a weightless balanced beam, 52 N acts 5 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
4Forces & equilibriumA 10 kg cart has horizontal forces 89 N right and 73 N left. No other horizontal forces act. Taking right as positive, find its acceleration. Round to 3 decimal places if needed. Answer in m/s².
m/s²
5Energy, work & powerA model device transfers energy at constant power 550 W for 66 s. Find the transferred energy. Round to 3 decimal places if needed. Answer in J.
J
6Energy, work & powerA device receives 990 J and has useful-energy efficiency 15%. Find the useful output energy. Round to 3 decimal places if needed. Answer in J.
J
7Pressure & fluidsA normal force of 37 N acts uniformly over 0.83 m². Find the pressure. Round to 3 decimal places if needed. Answer in Pa.
Pa
8Pressure & fluidsConvert 5000 cm² to square metres.
m²
9Waves & soundA wave has frequency 28 Hz and wavelength 4.9 m. Find its speed. Round to 3 decimal places if needed. Answer in m/s.
m/s
10Waves & sound39 complete oscillations take 13 s. Find the period. Round to 3 decimal places if needed. Answer in s.
s
11Electricity & circuitsA model device uses constant power 525 W for 10 h. Find the energy in kilowatt-hours. Round to 3 decimal places if needed. Answer in kWh.
kWh
12Electricity & circuitsA constant current of 2.9 A flows for 139 s. Find transferred charge. Round to 3 decimal places if needed. Answer in C.
C