Topic 2 Flashcards
what is the difference between speed and velocity?
Speed is scalar, and uses distance
velocity is a vector and uses displacement
what is the difference between scalar and vector quantities?
Scalar is only magnitude
vector is magnitude and direction
list the scalar quantities
Time (s) distance (m) temperature (K) speed energy (J) Power (J/s) voltage (v) Resistance (ohm)
list the vector quantities
Displacement (m) velocity acceleration (m/s-2) momentum (Nm) Force (includes weight) (N) moments (Nm)
What is newtons first law?
A resultant force is needed to make an object accelerate or decelerate, if the forces are balanced the object is either stationary or moving at a constant speed
What is newtons second law?
F=ma, tells us how quickly an objects motion will be changed by a resultant force
What is newtons third law?
For every force there is an equal and opposite reaction force
List the needed info for displacement time graphs
If negative on y-axis movement is in the opposite direction
Can see how far an object as moved
Flat line = no movement
Gradient gives velocity (Δs/Δs=v)
List the needed info for velocity time graphs
Flat line = constant velocity Negative is in the opposite direction Slanted lines = acceleration or deceleration Gradient = acceleration (v-u/t=a) Area under the line = distance traveled
Acceleration time graphs
How acceleration changes over time
What must be constant for suvat to work?
Acceleration
Which suvat equation does not contain distance
v=u+at
Which suvat equation does not contain acceleration
s=((u+v)/2)*t
Which suvat equation does not contain final velocity
s=ut+0.5*at^2
Which suvat equation does not contain time
v^2=u^2+2as
