motion
what does motion mean?
the object changing in its positions overtime
A 50 kg skater pushed by a friend accelerates 5 m/sec2. how much force did the friend apply?
250N
Wheels on a skateboard most likely experiences-
Rolling Friction
What is the SI unit used to measure force?
newtons
What law is best described by inertia?
1st
what is the formula for speed
s=d/t
How much force is needed to accelerate a 3kg skateboard to 5m/s2
15N
How does friction affect speed?
more friction decreases speed
As distance between two objects increase the pull of gravity
Decreases
Equal and Opposite
3rd
what is the definition of velocity
rate of change in position
A 20 kg bike accelerates at 10 m/s2. What was the force?
200 Newtons
What are 2 factors that determine the amount of friction between 2 objects?
Force and roughness between surfaces
The force of gravity acting on an object is the object's ______.
weight
A magician pulls a tablecloth out from under dishes and glasses on a table without disturbing them.
newton's 1st law
the measure of how quickly something moves or the distance it moves in a given amount of time is called
speed
A force of 250N is applied to an object that accelerates at a rate of 5 m/sec2. What is the mass of the object?
50kg
Rough surfaces have _________ compared to smoother surfaces.
greater friction
The law of universal gravitation is credited to whom?
newton
A person not paying attention while skateboarding hits a rock. The skateboard stops...they don't.
the law of inertia (1st law)
a vector whose length is the shortest distance from the initial to the final position of a point undergoing motion
displacement
If you increase the mass on an object, its acceleration (a) ____
decreases
Which of these materials do you predict would have the MOST amount of friction
sand paper
The amount of matter in an object is
mass
What Unit do we Measure Force in?
newtons