Describing motion Flashcards
What is the acceleration of gravity?
All falling objects accelerate at the same rate (not counting friction of air resistance). Downward velocity increases by 10m/s with each second of falling.
What is the acceleration of gravity on earth?
10 m/s^2
What is velocity?
Speed and direction
What is speed?
The rate at which an object moves
Speed = distance/time –> units of m/s
What is acceleration in general?
Any change in velocity. Units of speed/time (m/s^2)
What is momentum?
Momentum = mass x velocity
- Only way to change an objects momentum is to apply a force to it
What is net force?
A net force changes momentum and generally means an acceleration (change in velocity)
What is angular momentum?
Rotational momentum of spinning or orbiting an object
What is mass?
the amount of matter in an object (this doesn’t change in space)
What is weight?
the amount of matter and forces applied to an object (this can change in space)
What happens in free fall?
You are weightless
Why are astronauts weightless in space?
There is gravity in space, however weightlessness is due to a constant state of free fall
What does force cause?
Change in momentum, which produces acceleration
How did Newton change our view of the universe?
Realized the same physical laws that operate on earth also operate in the universe
What is Newton’s first law of motion?
An object moves at constant velocity unless a new force acts to change its speed or direction
