BMST - Basic Math and Science Newton's Laws of Motion Questions and Answers 3 — Questions and Answers
Question 1: A 5 kg box is pushed with a net force of 20 N. What is its acceleration?
- 2 m/s²
- 4 m/s² (Correct answer)
- 100 m/s²
- 0.25 m/s²
Correct answer: 4 m/s²
By Newton's Second Law, a = F/m = 20/5 = 4 m/s².
Question 2: Which of Newton's laws explains why a rocket accelerates when it expels gas?
- First Law
- Second Law
- Third Law (Correct answer)
- Law of Gravity
Correct answer: Third Law
The rocket expels gas backward (action) and is pushed forward (reaction), illustrating Newton's Third Law.
Question 3: A car traveling at 30 m/s comes to a sudden stop. A passenger continues to move forward. This is best explained by:
- Newton's Third Law
- Newton's First Law (Correct answer)
- Newton's Second Law
- The law of friction
Correct answer: Newton's First Law
Newton's First Law states an object in motion stays in motion unless acted upon by an external force.
Question 4: Two objects, one with mass 2 kg and one with mass 8 kg, experience the same net force. Which has the greater acceleration?
- The 8 kg object
- The 2 kg object (Correct answer)
- Both have equal acceleration
- Cannot be determined
Correct answer: The 2 kg object
Since a = F/m, the smaller mass (2 kg) produces a greater acceleration for the same force.
Question 5: A person pushes a wall with 50 N of force. According to Newton's Third Law, the wall pushes back with:
- 25 N
- 100 N
- 50 N (Correct answer)
- 0 N
Correct answer: 50 N
Newton's Third Law states action and reaction forces are equal in magnitude but opposite in direction.
Question 6: An object at rest on a table has zero net force acting on it. This is consistent with which law?
- Newton's Third Law only
- Newton's First Law (Correct answer)
- Newton's Second Law only
- None of Newton's laws
Correct answer: Newton's First Law
Newton's First Law states that an object at rest remains at rest when the net force is zero.
Question 7: A 10 kg object accelerates at 3 m/s². What net force is acting on it?
- 3.3 N
- 13 N
- 30 N (Correct answer)
- 0.3 N
Correct answer: 30 N
By Newton's Second Law, F = ma = 10 × 3 = 30 N.
BMST - Basic Math and Science Newton's Laws of Motion Questions and Answers 3
A 5 kg box is pushed with a net force of 20 N.
What is its acceleration?