Newton's Laws
What is Newton’s First Law?
This law says an object at rest stays at rest unless acted on by an unbalanced force.
What is the formula for speed?
Distance divided by time
This quantity measures how far an object travels regardless of direction.
distance
a push or pull exerted on an object in order to change the motion of the object; has size and direction.
force
The equation for Newton’s Second Law.
F=ma (force = mass x acceleration)
How is veolcity different from speed?
Velocity differs from speed because it includes direction.
This quantity measures the change in position from start to finish and includes direction.
displacement
quantity that has just a number
scalar
Newton’s Third Law says forces always come in these.
Action and reaction. Every action has an equal and opposite reaction.
A car travels 120 m in 6 s. Find its speed.
v=120 / 6 =20 m/s
Which can be negative: distance or displacement
displacement
a quantity that has both size and direction.
vector
A 10 kg object accelerates at 2 m/s². Find the force.
10 x 2 = 20N
A car speeds up from 10 m/s to 30 m/s in 5 seconds. Find the acceleration.
a= (30-10) / 5 = 4 m/s^2
A student walks 5 m east and then 5 m west, ending where they started. What is their displacement?
0 m
a location to which another location is compared
reference point
Why do passengers lurch forward when a car suddenly stops?
inertia
An object moving at 20 m/s slows to 5 m/s in 3 seconds. Find the acceleration.
a=(5-20) / 3 =−5 m/s^2
A runner completes one full lap around a 400 m track and ends at the starting point. The distance and displacement are.....
400 m distance and 0 m displacement
the combination of all the forces acting on an object.
net force