Forces Practice — Newton's Laws Problems
10 problems · instant feedback · full explanations
Forces are about the net push or pull. Before calculating, always ask: what are all the forces, and what is left over after they cancel? That leftover net force is what F = ma talks about.
Q1.
A 6 kg object accelerates at 4 m/s². What is the net force acting on it?
Multiple choice · Easy
Q2.
What does the inertia of an object describe?
Multiple choice · Easy
Q3.
A rocket rises because of which action-reaction pair?
Multiple choice · Medium
Q4.
What net force is needed to accelerate a 6 kg cart at 4 m/s²?
Numerical answer (N) · Easy
Q5.
A 75 kg skater is pushed with a net force of 150 N. What is her acceleration?
Numerical answer (m/s²) · Medium
Q6.
A 20 kg crate slides on a floor with coefficient of kinetic friction μ = 0.3. What is the friction force opposing the slide? (g = 9.8 m/s²)
Numerical answer (N) · Medium
Q7.
True or false: action-reaction force pairs cancel each other out, so nothing can ever accelerate.
True / False · Medium
Q8.
A 70 kg person stands on a scale in an elevator accelerating upward at 2 m/s². What does the scale read? (g = 9.8 m/s²)
Multiple choice · Hard
Q9.
An 8 kg box is pushed right with 50 N while kinetic friction of 18 N opposes the motion. What is the box's acceleration?
Numerical answer (m/s²) · Hard
Q10.
An astronaut travels from Earth to the Moon. What happens to her mass and weight?
Multiple choice · Medium