M3C5

Question 1

What’s Newton’s first law of motion?

Answer 1

A body will remain at rest or continue to move at a constant velocity until external forces act upon it

Question 2

What’s Newton’s second law of motion?

Answer 2

The resultant force on an object is proportional to the rate of change in momentum, when the change of momentum is in the direction of the force

Question 3

What’s Newton’s third law of motion?

Answer 3

If object A exerts a force on object B then object B will exert and equal and opposite force on object A

• All forces must be of the same type
• All force must be opposite
• All forces must act upon different bodies

Question 4

Define the conservation of momentum

Answer 4

The total momentum before a collision is always equal to the total momentum after the collision, provided that no external force are involved

Question 5

Define linear momentum

Answer 5

The mass of an object multiplied by it’s velocity

Question 6

What’s the equation for linear momentum?

Answer 6

ρ=mv
ρ = momentum (Kg m s^-1 or Ns)
m = mass (Kg)
v = velocity (m s^-1)

Question 7

What are some of the equations we can substitute linear momentum into?

Answer 7

Fd = 1/2mv^2 - 1/2mu^2
Ft = mv - mu
F = force (N)
d = displacement (m)
m = mass(Kg)
v = velocity (m s^-1)
t = time (s)