Force of Gravity
Friction
FBD
UFC
Newton's laws
100
what units does gravity use?
Kg
100
What are the 2 types of Friction?
Static and Kinetic
100
What 2 Forces are always being applied on earth?
Fn and Fg
100
Define UFC
Moving in a circular path at a constant speed.
100
What units are newtons law in?
Newtons(N)
200
What is the basic formula for gravity
Fg=mg
200
What is the coefficient of Friction?
μ
200
What forces are being applied to a book being pushed against a wall?
Up= Ffr
Right=Fa
Down=Fg
Left=Fn
200
UCM equation for speed?
V=2πr/Τ
200
What is newton's first law of motion?
An object at rest remains at rest unless acted on by a non-zero net force.
300
Which direction is gravity being applied on a person standing still?
down
300
Equation for static friction?
Ffs=μs Fn
300
which axis does sinθ follow
x-axis
300
UCM equation for acceleration?
ac⃑= v2/r
300
What is Newton's second law of motion equation?
Fnet=ma
400
Q: If a elevator is standing still and the person inside is 60kg. how would you solve for Fn
Fn=Fg+ma
Fn=mg+ma
Fn=600+609.8
Fn=588N
400
Equation for Kinetic friction?
Ffk=μk Fn
400
X: Facosθ-Ffr=ma
Y: Fn-Fasinθ-Fg=ma
Facosθ-Ffr=ma
Fn=Fasinθ+Fg
400
Q:Find the speed of a person standing on the equator of the Earth, due to the Earth’s rotation on its axis (RE=6,378,100 m)
V=2π(6,378,100)/86400=463.6 m/s
400
What do you need to be able to use newton's 3rd law?
2 forces acting upon each other.
500
Q: If an elevator is going down at 1 m/s^2 and you are 60Kg what is Fn?
Fn=Fg+ma
Fn=mg+ma
Fn=60-1+609.8
Fn=528N
500
Q: push a 10kg box across the floor (μs = 0.7 and μk=0.3). then push the box with 50 N of force, parallel to the floor. Find the force of friction
Ffr=(.7)(10)(10)
Ffr=70n>Fr
500
X: no forces
Y: Fa-Fg-Fn=ma
Fa=Fg+Fn
500
Q:Find centripetal acceleration of a person standing on the equator of the Earth, due to the Earth’s rotation on its axis (RE=6,378,100 m)
ac⃑= 463.6(2)/6,378,100= .0034m/s2
500
A train is traveling at a speed of 30m/s and a car is travelling at 15m/s. If the train and the car collide head on, which will experience more force? Which will experience more acceleration?
Newton’s 3rd law tells us that the two will experience the same force. Newton’s 2nd law tells us that the car will accelerate much more than the train because it is smaller.