P8 Forces Flashcards
What is inertia
When an object resist changes in its state of motion
What is a scaler
Physical quantities that have size/magnitude but no direction
What is a vector
Physical quantities that have size/magnitude and direction
What are contact forces
Two object must interact to create a contact force
What are non-contact forces
They dont need to directly touch to interact to ceate a force
What are some non contact forces
Magnetic force, electrostatic force, gravitational force
What are contact forces
Friction, air resistance , stretching
What are some scalar quantities
Temperature, mass, speed, time and volume
What are some vector quantities
Resultant Force, acceleration, displacement, momentum, velocity
What is newtons first law
Inertia, an object remains in the same state of motion unless a resultant force acts on it
What is resultant force
The single force that replaces all the forces acting on an object by adding them together
What is newtons 2nd law
Resultant force = mass x acceleration
What is newtons 3rd law
When 2 object interact , they exert an equal and opposite reaction
What is displacement
A distance an object moves , measured in a straight line from start to end point
What 3 things can a force do
Make an object change shape, motion and state of rest
Speed is
Distance / time
Force is
Mass X acceleration
Velocity is
Displacement / time
If forces are balanced on a stationary object
The object remains stationary
If forces are balanced on an object already in motion
The object stays at a constant velocity
If forces are unbalanced on a stationary or non stationary object
That will result in acceleration or deceleration
What is moments
A moment is the turning effect of a force
What is a pivot
Where something rotates around
How do you calculate moments
Force X distance
What are pulleys and gears
Simple machines to transmit rotational forces also to increase or decrease rotational force
How do you calculate moment by using gears
Moment = force X gear radius
What happens when you use gear 1 on a bike
There is a high turning effect and a low speed
What happens when you use gear 6 on a bike
There is a low turning effect and high speed
What is a gear
A gear is used to transfer motion from one place to another
What is a lever
A lever is a wooden or metal rod which it used to move an object
