IB Physics HL A.2.2 Applications of Newton’s Laws
Practise analysing coupled blocks, frictional forces and multi-stage motion with Newton’s laws.
- Syllabus
- First assessment 2025
- Course
- Physics HL
- Level
- HL
Practise analysing coupled blocks, frictional forces and multi-stage motion with Newton’s laws.
A girl on a sledge is moving down a snow slope at a uniform speed.

After leaving the snow slope, the girl on the sledge moves over a horizontal region of snow. Explain, with reference to the physical origin of the forces, why the vertical forces on the girl must be in equilibrium as she moves over the horizontal region.
gravitational force/weight from the Earth «downwards» reaction force from the sledge/snow/ground «upwards» no vertical acceleration/remains in contact with the ground/does not move vertically as there is no resultant vertical force
Marking guidance:
Allow naming of forces as in (a)
Allow vertical forces are balanced/equal in magnitude/cancel out