PHYSICS CONNECTION
Maintaining speed requires power
Power measures how quickly a force transfers energy. A vehicle moving at constant speed can still require substantial power to overcome resistance.
P = Fv
Follow the reasoning
- Find the relevant force component along the motion.
- Use the speed at the same instant.
- Multiply them and interpret the result as an energy-transfer rate.
OFFICIAL OCR QUESTIONS
Try it in a past paper 2
Open the question, then use its mark scheme to check your work.
Question 5(b)
Derive power equals force times speed and apply it to a trolley moving up a slope.
Question 6
Resolve the pulling force to calculate motor power at constant speed.
A curated collection checked against the question papers and mark schemes; not a complete past-paper catalogue. Links open official OCR PDFs in a new tab.
ORIGINAL PHYSICSUK QUESTIONS
Put the ideas to work
More practice is on its way
No PhysicsUK question linked yet. New eligible questions appear here as the bank grows.
Specification outcomes (3)
- 3.1.1(a) Define and use displacement, instantaneous speed, average speed, velocity and acceleration.
- 3.3.3(a) Define power, the unit watt, and use P = W / t.
- 3.3.3(b) Use and derive P = Fv from first principles.