Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
25 Cards in this Set
- Front
- Back
|
Centripetal Acceleration formula?
|
v2/r
|
|
|
What is uniform circular motion?
|
An object moving in a circular path at a constant speed.
|
|
|
What direction is the velocity of an object in uniform circular motion?
|
At a tangent to the circle at that point
|
|
|
Period?
|
Time for one rotation
|
|
|
Speed in circle?
|
(πr^2)/T
|
|
|
Newtons first law?
|
An object at rest will stay at rest and an object in motion will stay in motion unless acted upon by an external net force.
|
|
|
Newtons second law?
|
a=F/m
An objects acceleration is directly proportional to its net force, in the direction of the force, and inversely proportional to it's mass. |
|
|
The force causing acceleration is directed where?
|
Towards the middle of the circle
|
|
|
What causes centripetal acceleration?
|
When a force perpendicular to an object with a constant velocity acts upon an object, remaining perpendicular as the direction changes.
|
|
|
Example of tension force?
|
A boy spinning a yoyo
|
|
|
Example of Frictional force?
|
A car racing around a circular bend
|
|
|
Example of gravitation centripetal force?
|
Moon around earth, earth around sun
|
|
|
Example of normal force?
|
A car turning a banked corner, relying only on normal force.
|
|
|
Name two vertical forces with constant velocity on flat road.
|
Weight of car and Normal force.
|
|
|
Weight?
|
W=mg
|
|
|
Normal force?
|
F= frictional force + horizontal component of normal force
So ma=F + Fsin0 and... (mv^2)/r = Frictional force + Fsin0 |
|
|
Gravitational force
|
F = Gravitation force
(mv^2)/r = (Gm1m2)/r^2 |
|
|
How is T=2πmv/F given?
|
We know that F=mV^2/r so we rearange the equation for r. Then, by substuting r into the equation for the period (T=2πr/v) we find the equation.
|
|
|
Frictional force equation?
|
F=(mv^2)/r
|
|
|
Why is it harder for a car to go faster around a bend?
|
As the speed increases around the curve a larger acceleration is needed and therefore a larger force is required.
|
|
|
Why can a car travel faster around a banked curve?
|
A banked curve allows for a second force (the horizontal component of the normal force) to act upon the car in addition to the frictional force. Because of this there is more force available and hence a greater speed can be achieved.
|
|
|
Name the force forces acting on a car moving forward.
|
Behind: Total resistance force (Drag)
Forwards: Force created by engine Up: Normal force Down: Weight of car (gravity) |
|
|
What causes centripetal acceleration when on a car?
|
When a car in motion turns its wheels, the wheels push against the road, and the road pushes back with a force perpendicular to the direction of the cars velocity. This creates centripetal acceleration!
|
|
|
Explain if grease is on a road where a car is trying to turn?
|
The grease decreases the force acting perpendicular to the cars velocity. Therefore there would be less force available to change the cars direction and the car may slip instead of following the road.
|
|
|
If a car locks its steering a goes around a bend that does not rely on friction, what happens?
|
The car will move towards the bend as the force provided is greater than the force needed to follow the path of the radius.
|
