P2.1 Flashcards
(36 cards)
What’s a force?
A push or pull with direction and a vector
What are balanced forces?
When forces acting on something cancel each other out
What are unbalanced forces?
When the forces acting on something don’t cancel each other out, so it moves away from the greater force
What is an example of balanced forces?
When a person sits on a chair
What is an example of unbalanced forces?
When a person jumps out of a plane and falls towards the ground
What is Newton’s Third Law?
Every action has an equal and opposite reaction
What is resultant force?
When two or more forces act on an object at once
What 3 things do resultant forces do?
Change speed of an object
Change the direction of an object
Change the shape of an object
What is speed?
The rate of change of direction
What is velocity?
Speed with direction
What is acceleration?
The rate of change of velocity
What does velocity have?
Speed
Direction
How do you find the distance in a distance/time graph
Area under the graph
Cut shape into triangles + rectangles
1/2 b*h for triangles
b*h for rectangle
\+ together
= total distance travelled
What is air resistance caused by?
Moving objects pushing air particles out of the way
What is stopping distance?
The time that it takes from a driver to see a stop sign, to when the car has stopped
(thinking distance+braking distance)
What is thinking distance?
The distance that it takes for a driver to react to a stimulus
What factors affect thinking distance?
Increase: Alcohol Fatigue Badly lit roads Distractions (e.g music)
Decreases:
Stimulants
What factors affect braking distance?
Increases:
Icy roads
Worn tires
Amount of people in the car
Decreases:
New roads
What’s braking distance?
The distance travelled by the car when the brakes are on
What type of force do brakes provide for a car?
Backwards
What’s terminal velocity?
When something is falling at a constant speed
What is Hooke’s Law?
The force put on a spring is directly proportional to the extension
What is mass?
A measure of the amount of matter that makes up an object
The same regardless of where you are
What is weight?
A measure of the force acting on your mass caused by a gravitational field
(Changes depending on the gravitational field you’re in)
