OCR A asks you to apply one equation for motion with uniform (constant) acceleration:
- v is the final velocity in m/s, u is the initial velocity in m/s, a is the acceleration in m/s² and s is the distance in metres.
- Use it when the time is not given. Substitute the known values, then rearrange for the quantity you need.
Quick Check: A car speeds up from 10 m/s to 20 m/s while travelling 75 m with uniform acceleration. Calculate the acceleration.
v² − u² = 2as, so 20² − 10² = 2 × a × 75. That gives 300 = 150a, so a = 2 m/s².
This key facts covers OCR A (J249): Motion with Uniform Acceleration within Newton's Laws of Motion for GCSE Physics. Revise Newton's Laws of Motion in Forces for GCSE Physics with 18 exam-style questions and 15 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 15 of 17 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Newton's Laws of Motion
According to Newton's First Law, what happens to an object when there is no resultant force acting on it?
A spaceship is travelling through deep space far from any planets. The engines are switched off. Explain what will happen to the motion of the spaceship and why.