Newton's 1st + 2nd Laws - Paper 1 Flashcards
State Newton’s First Law of Motion
A stationary object will remain stationary and a moving object will continue moving at a constant velocity if the resultant force acting on it is zero
If the resultant force acting on a stationary object is zero, describe its motion
Remains stationary
If the resultant force acting on a moving object is zero, describe its motion
Continues moving at a constant velocity
Define velocity
A vector quantity measuring rate of change of displacement
Displacement - the distance moved in a straight line, in a given direction, from the starting point
Give the equation for Newton’s Second Law of Motion
F=ma
State Newton’s Second Law of Motion
An object’s acceleration is directly proportional to the resultant force acting on it
but inversely proportional to its mass
Give the 5 forms of acceleration as a consequence of a resultant force acting on an object
Starting
Stopping
Speeding up
Slowing down
Changing direction
Define acceleration
Rate of change of velocity
a = Δv/Δt
Give the equation for acceleration with change in velocity
a = Δv/Δt
Which of the 5 forms of acceleration is taken by an object depends on its what?
Initial motion
Define Inertia
The tendency for an object’s motion to remain unchanged
Define Inertial mass
how difficult it is to change an object’s velocity
Give the equation for inertial mass
m=F/a
(rearranged F=ma; Newton’s Second Law)
What does it mean for an object to have a lot of inertia?
It has a strong tendency to resist changes in its motion
difficult to start or stop moving due to its large mass
Give an example of an object which has a lot of inertia
The Moon
It has a large mass and so resists changes to its motion
Define Resultant Force
Sum of all forces acting on an object
You get a resultant force if forces acting on an object are unbalanced
