GCSE Physics: Forces and Motion 1 — Questions and Answers
Question 1: What is Newton's First Law of Motion?
- An object remains at rest or in uniform motion unless acted on by a resultant force. (Correct answer)
- Force equals mass times acceleration.
- Every action has an equal and opposite reaction.
- The acceleration of an object is proportional to the net force applied.
Correct answer: An object remains at rest or in uniform motion unless acted on by a resultant force.
Newton's First Law states that an object will stay at rest or continue moving in a straight line at constant speed unless a resultant (unbalanced) force acts on it.
Question 2: A car of mass 1,000 kg accelerates at 3 m/s². What is the resultant force acting on it?
- 333 N
- 1,003 N
- 3,000 N (Correct answer)
- 300 N
Correct answer: 3,000 N
Using F = ma: F = 1,000 kg × 3 m/s² = 3,000 N.
Question 3: Which of the following is a vector quantity?
- Speed
- Mass
- Temperature
- Velocity (Correct answer)
Correct answer: Velocity
Velocity is a vector quantity because it has both magnitude and direction, unlike speed which only has magnitude.
Question 4: A ball is dropped from rest and falls 5 m. Using g = 10 m/s², what is its speed just before hitting the ground?
- 5 m/s
- 10 m/s (Correct answer)
- 50 m/s
- 100 m/s
Correct answer: 10 m/s
Using v² = u² + 2as: v² = 0 + 2 × 10 × 5 = 100, so v = 10 m/s.
Question 5: What does the gradient of a distance-time graph represent?
- Acceleration
- Speed (Correct answer)
- Force
- Momentum
Correct answer: Speed
The gradient (slope) of a distance-time graph gives the speed of the object at that point.
Question 6: When two ice skaters push off each other, they move in opposite directions. This demonstrates which law?
- Newton's First Law
- Newton's Second Law
- Newton's Third Law (Correct answer)
- The Law of Conservation of Energy
Correct answer: Newton's Third Law
Newton's Third Law states that for every action there is an equal and opposite reaction, which causes both skaters to move apart.
GCSE Physics: Forces and Motion 1
What is Newton's First Law of Motion?