Dynamics

Question 1

Mass

Answer 1

🔹A measure of the amount of matter in an object.

Question 2

Weight

Answer 2

🔹the force of gravity acting on an object.

🔹the effect of a gravitational field on an object.

🔹 Vector quantity.

Question 3

Newton’s first law of motion

Answer 3

🔹It states that a body will remain at rest or move with constant motion, unless acted on by a resultant force.

Question 4

Newton’s second law of motion

Answer 4

🔹It states that a resultant force acting on a body will cause a change in momentum in the direction of the force.

🔹The rate of change of momentum is proportional to the magnitude of the force.

Question 5

Newton’s third law of motion

Answer 5

🔹If body A exerts a force on body B then body B will exert a force on body A of equal magnitude but in the opposite direction.

🔻must act on different objects
🔻must be the same type of force

Question 6

The principle of conservation of momentum

Answer 6

The total momentum of a closed system remains constant provided that no external force acts on it.

Question 7

How do you know if a collision is elastic or inelastic?

Answer 7

🔹 If it’s kinetic energy before and after a collision is conserved it is elastic and if it isn’t conserved than it’s inelastic collision.

🔹Most of the times in elastic collisions objects move in opposite directions and in inelastic collisions, they stick together after collision.