Motion and Forces Flashcards
Vector Quantity
A quantity that has both magnitude and an associated direction
Scalar quantity
Just size or magnitude
Speed Equation
Average speed = Distance travelled / time taken or V=X/T or to calculate distance travelled by object X = VT
What does a horizontal line on a distance time graph mean?
It means the object has stopped moving and is stationary
Speed from gradient equation
Speed = Distance / Time
Acceleration equation
Acceleration = Change in velocity / Time taken
Define Velocity
Velocity is a constant force that has a direction eg: Car moving at 40mph FORWARDS
Newtons 1st Law
An object remains in the same state of motion unless a resultant force acts upon it.
Newtons second law
F = MA (force = mass x acceleration)
Inertial Mass
Inertial mass is a measure of how difficult it is to change the velocity of an object. You use NEWTONS SECOND LAW
Newtons 3rd Law
Whenever 2 objects interact they exert equal and opposite forces upon each other.
Define Weight
mass x gravity
Momentum calculation
P = MV (p= momentum, mass = m, Velocity = V)
Describe the conservation of momentum
Total momentum before the event = Total momentum after the event (in a closed system)
How do cars minimize the impact in a crash
The force of the collision is equal to the rate of change of momentum. Crumple zones increase the time it takes for the impact to occur, seatbelts stop you from flying out the window and airbags minimize impact by dissipating force through a gas. ALL of them decrease the rate of change of momentum
