Chapter 10 - Forces and motion Flashcards
What is Newton’s first law?
An object will remain at rest or continue at a constant speed in a straight line unless there is an unbalanced force acting upon it.
What is Newton’s second law?
F=ma
What is Newton’s third law?
For every action there is an equal and opposite reaction.
What is weight?
The force acting upon an object due to gravity.
What is the strength of gravity on Earth?
9.8 N/kg
What is the terminal velocity of an object?
When the frictional force on an object is equal and opposite to its weight.
What is the resultant force when an object is moving at terminal velocity?
Zero.
Unit for momentum.
kg m/s
What is the conservation of momentum?
The total momentum before an event is equal to the total momentum after
What is the formula for the conservation of momentum?
m1 x v1 = m2 x v2
Is momentum a vector or scaler quantity?
Vector
What happens when 2 vehicles collide?
They exert equal and opposite forces on each other and their total momentum is unchanged.
What is the formula for impact force?
impact force = change in momentum/impact time
What is Hooke’s law?
The extension of a spring is directly proportional to the force applied, as long as its limit of proportionality is not exceeded.
