P4 Flashcards
Equation for GPE?
mgh
Equation for KE?
½ mv^2
Equation for Resultant force?
mass (kg) × acceleration (m/s2)
What can return journeys be visualized on?
a displacement-time graph.
On a displacement-time graph, what would the displacement be if the vehicle traveled behind its starting speed?
negative.
On a displacement-time, what happens when a vehicle would have returned to its start point?
The displacement would be zero.
When does friction occur?
When two surfaces slide over one another. It acts to oppose the motion.
What does the size of the friction force depend on?
- how hard the surfaces are pushed together (weight of the object).
- the roughness of the surface (rougher surfaces give more friction).
What happens to friction when you increase the applied force?
It will also increase.
What is limiting friction?
When it reaches a maximum value.
What do displacement-time graphs represent?
How the position of an object relative to a fixed point (represented by the origin) changes as time progresses.
What are the forces acting on a car?
- Friction- between the road and the tyres
- Gravity- pulls down the car
- The reaction force from the road pushes on the wheels.
- Air resistance- acts on the front of the car.
What does negative gradient indicate on a displacement-time graph?
That it is moving in the oposite dirextion so it finishes where it started.
What does a slope mean on a displacement-time graph?
Velocity
What does the y-intercept equal to on a displacement-time graph?
Initial displacement.
