Question pattern · Knowledge card
Projectile with fluid resistance
Explain resisted motion from the direction of drag relative to velocity. Keep the treatment qualitative unless a resistance model is explicitly supplied.
- Primary skill
- Explain & reason
- Original practice questions
- 2
Connect the ideas
Key relationships and graph reading
- Drag acts opposite to instantaneous velocity
- Acceleration changes as velocity and drag change
- Terminal speed occurs when the resultant force becomes zero
Check your method
Three common mistakes
- Keeping horizontal velocity constant when drag acts.
- Keeping acceleration equal to g throughout resisted fall.
- Treating terminal speed as zero speed.
Original micro-example
Try the idea in miniature
Two identical paper cones fall, but one is opened wider and experiences more drag at the same speed.
Show the short answer
The wider cone has a smaller downward resultant force at that instant, so its downward acceleration is smaller and it approaches a lower terminal speed.
Original practice questions
Practise this question pattern
The pattern describes the reasoning structure. Each link below opens a distinct original practice question.
Medium4 marks
Compare ideal and resisted projectile motion
Explain & reason
Start original questionMedium4 marks
Approach to terminal speed
Evaluate & predict
Start original question