Q What is meant by the term “resultant force”?
Answer: It is the single force that has the same effect as the combined forces acting on a body.
Q Describe linear momentum conservation.
Answer: In the absence of external force, the total momentum of a system remains constant.
Q What happens to the velocity of a body if the net force is zero?
Answer: The velocity remains constant.
Q What is the relationship between mass and inertia?
Answer: Higher mass means greater inertia.
Q How does increasing mass affect momentum?
Answer: Momentum increases proportionally with mass if velocity remains constant.
Q What does the term “reaction force” mean?
Answer: Reaction force is the force exerted by a body in response to an applied force.
Q Why does a ball stop rolling on the ground after some time?
Answer: Due to the force of friction acting opposite to the motion.
Q What is the unit of momentum?
Answer: The SI unit of momentum is \( \text{kg·m/s} \).
Q How is acceleration related to force and mass?
Answer: \( a = F/m \), where \( a \) is acceleration, \( F \) is force, and \( m \) is mass.
Q State one practical application of Newton’s Third Law.
Answer: A rocket moves upward due to the downward expulsion of gases.
Q What does the term “net force” mean?
Answer: The net force is the vector sum of all the forces acting on a body.
Q Explain the term “impact force.”
Answer: Impact force is the high force or shock applied over a short time when two objects collide.
Q Why is a seatbelt necessary in a moving car?
Answer: A seatbelt prevents the passenger from moving forward due to inertia during a sudden stop or collision.
