P2.2 The kinetic energy of object speeding up or slowing down Flashcards
When a force causes an object to move through…
A distance work is done
What is the equation for work done?
W = F x d
What does w stand for?
Work done
What is work done measured in?
Joules
What does the d stand for?
The distance moved in the direction of the force in metres
What is transferred when work is done?
Energy
What is power?
The work done or energy transferred in a given time
What is the equation fro power?
E
P = —–
t
What is power measured in?
Watts
What does the E stand for?
The energy transferred in joules
What happens when an object is raised vertically?
Work is done against gravitational force and the object gains gravitational potential energy
What is the equation for change in gravitational potential energy?
Ep = m x g x h
What does Ep stand for?
Change in gravitational potential energy in joules
What does g stand for?
Gravitational field strength in N/kg
What does h stand for?
Change in height in metres
What does the kinetic energy of an object depend on?
Its mass and its speed
What is the equation to find the kinetic energy?
1
Ek = —– x m x v2
2
What does Ek stand for?
Kinetic energy in joules
What does v stand for?
Speed in m/s
What is momentum?
The tendency of a moving object to keep moving in the same direction, it is a property of moving objects
What is the equation for momentum?
p = m x v
What does the p stand for?
Momentum in kilograms metres per second, kg m/s
In a closed system what is the total momentum before an event compared to the total momentum after the event?
Equal / the same
What is the name for when the total momentum is the same before and after?
Conversion of momentum
