Question

Which forces cause changes in the motion of a system?

a) External forces only.

b) Internal forces only.

c) Both internal and external forces.

d) No forces can change the motion of a system.

Answer 1

Both internal and external forces cause changes in the motion of a system according to Newton's laws of motion.

Step-by-step explanation:

According to Newton's laws of motion, both internal and external forces can cause changes in the motion of a system. External forces act on the system from outside, while internal forces act between elements of the system. Only external forces affect the motion of the system, as stated by Newton's first law. Internal forces cancel out and do not contribute to the overall motion of the system.