8+9 revision Flashcards
What properties do vectors have?
magnitude and direction
What properties do scalars have?
Just magnitude, no direction
Is energy a vector or a scalar?
scalar
Is power a vector or a scalar?
scalar
Is force a vector or a scalar?
vector
Is weight a vector or a scalar?
vector
What is velocity?
speed in a particular direction
What is the formula for (average) velocity?
displacement/ time taken
What is the formula for (average) speed?
distance/ time taken
What is the relative velocity when two objects move in opposite directions?
The sum of the magnitudes of both velocities
What is the relative velocity when two objects move in the same direction
The difference between the magnitudes of the two velocities
How do you find the relative velocity of two objects?
Add the opposite of one velocity to both velocities. The resultant velocity not zero is the relative velocity.
What is the area under a velocity time graph?
The distance travelled
What happens when three forces acting on an object are in equilibrium?
The vectors form a closed triangle when added tip to tail
What is Newton’s first law?
An object will move at a constant velocity unless acted upon by an external force
What is Newton’s second law?
sum of forces = mass x acceleration
F=ma
What is Newton’s third law?
Every action has an opposite and equal reaction
How do you resolve a vector?
Split it into its horizontal and vertical components
When are suvat equations used?
When there is an acceleration and it is constant
What are the suvat equations?
v^2 = u^2+2as
v=u+at
s=ut + 1/2at^2
s=1/2(u+v)t
For which component is suvat used for projectiles?
The vertical (this is where acceleration happens)
When is the velocity 0 in the flight of an object?
At the top of the flight
When is work done?
When a force moves its point of application
What is the formula for work?
force x distance moved in direction of force
W=Fs
