CAIE IGCSE Physics Force in Circular Motion
Practise identifying the inward force perpendicular to circular motion and predicting how speed, radius and mass affect the force needed to maintain the path.
- Syllabus
- 2026–2028
- Course
- Physics 0625
Practise identifying the inward force perpendicular to circular motion and predicting how speed, radius and mass affect the force needed to maintain the path.
Fig. 2.1 shows a motorcyclist accelerating along a straight horizontal section of track.

Fig. 2.1
The motorcyclist and motorcycle have a combined mass of 240 kg .
At the end of the straight section, the track remains horizontal but bends to the right, as shown in Fig. 2.1.
When the motorcyclist reaches the bend, she travels around the bend in a circular path at a constant speed.
Explain why there must be a resultant force on the motorcyclist as she travels around the bend.
any two from:
- because there is an acceleration / change in velocity / change in direction / change in momentum (which needs a resultant force)
- motorcyclist accelerates / changes momentum (because velocity / direction changes)
- (resultant) force is perpendicular to the motion (of the motorcycle) OR a ∝F
B2