Flashcards in P2.3 & P2.4 Motions And Forces And Momentum, Energy, Work And Power Deck (33):
A runner runs a 400m race on a track. What is his distance and displacement?
On a distance-time graph, what does the gradient of the line show?
How do you calculate speed?
Distance(m) / time taken(s)
How do you calculate acceleration?
Change in velocity / time taken
What are the units for acceleration?
Which of these values is not acceleration?
All of them are acceleration
On a velocity-time graph, what does a straight line show?
What is a vector quantity?
A quantity which has size and direction
What forces can act on an object moving in the air?
When are forces balanced?
When the two forces acting against each other are the same
What factors affect acceleration?
What is the formula for force?
What are the units for force?
What is terminal velocity?
The velocity an object reaches when it falls when it cannot accelerate any further
What are the units for gravitational field strength?
Newtons per kilogram, N/Kg
What is the formula for weight?
Mass*gravitational field strength
What is thinking distance?
The distance that a car moves in the time that it takes a driver to react
What is braking distance?
The distance a car travels between the driver braking and it stopping
What is stopping distance?
Thinking distance*Braking distance
What factors affect thinking distance?
State of the driver eg
What factors affect braking distance?
What is the formula for momentum?
Kg m/s = Kg*m/s
What are crumple zones on a car?
Crumple zones are parts of the front on a car that can crumple on impact, which absorbs some of the energy in a crash
What is the formula for force relating to momentum?
Force = Change in momentum / time taken
F= mv-mu / t
N= kgm/s / s
What is the formula for work done?
Work done = force * distance moved
What is the formula for power?
Power = work done / time taken
P = E / t
W= J / s
What is the formula for Gravitational potential energy?
GPE = mass * GFS * vertical height
GPE= m * g * h
J = kg* N/kg * m
What is the formula for kinetic energy?
KE = 1/2 * mass * velocity2
KE = 1/2 * m * v2
J= 1/2 * kg * m/s2
What Is conservation of energy?
The GPE is the same as KE when it is transferred
How can you calculate distance from a velocity-time graph?
Velocity * time on the area underneath the line on the graph
Why can a space probe travel without fuel?
There is no air in space to slow it down
What is negative acceleration?