Newton's Laws & Gravitation is one of 9 topics in the Grade 11 Physical Sciences CAPS syllabus, covered across 3 lessons on Study Vault. Below are real practice questions from this topic with full worked answers.
Sample practice questions
Easy
1. The maximum static friction force is calculated using the formula:
fs(max) = mu(s) x N
fs(max) = mu(s) + N
fs(max) = N / mu(s)
fs(max) = mu(s) x m
Answer: fs(max) = mu(s) x N — The maximum static friction force is fs(max) = mu(s) x N, where mu(s) is the coefficient of static friction and N is the normal force.
Easy
2. Which type of friction acts on an object that is already sliding across a surface?
Kinetic friction
Static friction
Normal friction
Tension friction
Answer: Kinetic friction — Kinetic friction, fk = mu(k) x N, acts on an object that is already in relative sliding motion across a surface.
Medium
3. A 6 kg block rests on a horizontal surface with coefficient of static friction mu(s) = 0,4. Using g = 9,8 m.s^-2, calculate the normal force, N, in newtons.
Answer: 58.8 — On a horizontal surface with no vertical applied force, N = mg = 6 x 9,8 = 58,8 N.
