Physics 3 -Forces/energy Flashcards
what does velocity take into consideration that speed doesnt
velocity = direction
Distance in a particular distance is called what?
Displacement
Average speed (constant Acceleration) =
2
Gradient on a Distance/time graph =
Velocity
Downhill sections on a distance/time graph is
Going back to original point
Acceleration =
t
On velocity-time graph, flat sections represent what?
Whereas flat sections on distance/time graph represent what?
steady speed
Not moving
Area under a velocity/time graph is what
Distance
Gravitational force on earth is =
10m/s^2
10 N/Kg
Gravity gives an object …. and is different from….
weight
mass
Mass is the same where
Anywhere in the universe
Weight =
mass x gravitational force
m x g
If the resultant force is zero to a car, what will happen?
wont move
if the resultant force is zero to a moving car, what will happen
No change in velocity
A non zero resultant force will always end up producing what
Acceleration
acceleration =
F x a
what is newtons 2nd law
F=ma
what is newtons 3rd law
When two objects interact, the forces they exert on each other are equal and opposite
in terms of friction, the larger the area, the more what
Drag
What two forces are equal at terminal velocity
Resistance force (drag)
Accelerating force (weight)
stopping distance consists of what two things
Braking distance
Thinking distance
Momentum =
Mass x velocity
Kg) x (m/s
Momentum units =
kg m/s
Momentum before =
Momentum after
Force (momentum equation) =
time
When a force moves an object moves, what is transferred and what is done
energy transferred
work is done
Work Done =
Force x Distance moved in the direction of the force
E = F x D
Power =
time
Power is measured in
Watts (J/s)
Kinetic energy depends on both what
Mass + Speed
Ke =
0.5 x Mass x Speed^2
1/2MV^2
Whats the unit of Ke
Joules
If you double the speed, what happens to Ke
quadrouples
If you double the mass, what happens to Ke
Doubles
If you go twice as fast, what happens to stopping distance?
Quadrouples
If you have twice the mass, what happens to stopping distance
Doubles
Gravitaional Potential Energy =
Mass x g x height
falling objects convert GPE into what? What is this negating
KE
GPE can be dissipated into heat (due to air resistance)
