Forces and energy Flashcards
When a force causes an object to move through a distance, what is done?
Work is done.
Equation for work done:
W = Fd
Where:
W is work done (J)
F is force (N)
d is distance moved in direction of force (m)
What is transferred when work is done?
Energy.
Power is what?
Work done or energy transferred in a given time.
Equation for power:
P = E/t
Where:
P is power (W)
E is energy (J)
t is time (s)
Gravitational potential energy is what?
The energy that an object has by virtue of its postion in a gravitational field.
Equation for GPE:
Ep = mgh
Where: Ep is GPE (J) m is mass (kg) g is gravitational field strength (N/kg) h is change in height (m)
Kinetic energy of an object depends upon…
…speed and mass of the object.
Equation for kinetic energy:
Ek = (1/2)mv^2
Where:
Ek is kinetic energy (J)
m is mass (kg)
v is speed (m/s)
Momentum is what?
A property of a moving object.
Equation for momentum?
p = mv
Where:
p is momentum (kgm/s)
m is mass (kg)
v is velocity (m/s)
In a closed system, momentum after the event is…
…the same as before the event.
Examples of events with large amounts of momentum.
Collisions
Explosions
