What Forces Keep Objects in Circular Motion?

[mark9159]

You have one screwdriver with a thick handle and one with a thin handle. Which one would be better for opening a stubborn can of paint?

my answer: either screwdriver--they are the same

Which screwdriver would be better for turning a stubborn screw?

my answer: the thick handled screw driver

What force keeps the moon in orbit around the earth?
Choices: a.)centripetal force b.)gravitational force. c)both a and b
my answer: c) both a and b

You turn a corner in your car and slide to the outside edge of the seat. Why does this happen?
my answer: centrifugal force pulls you to the outside.

can someone explain the difference between centripetal and centrifugal forces please?

thank you,

mark

EDIT: one mor question

a coin stays on a turntable because of friction. Part of the friction causes cicular motion. Which direction does the friction point?
Choices: a) foward along the coin's path. b)towards the center of the turntable. c)away from the center of the turntable. d)backward along hte coin's path

my answer:..im not quite sure..could someone explain this to me

 

[Andrew Mason]

What force keeps the moon in orbit around the earth?
Choices: a.)centripetal force b.)gravitational force. c)both a and b
my answer: c) both a and b

Since gravity provides the centripetal acceleration, there is only one force. Gravity. a).

You turn a corner in your car and slide to the outside edge of the seat. Why does this happen?
my answer: centrifugal force pulls you to the outside.

can someone explain the difference between centripetal and centrifugal forces please?

Centripetal force is the force as measured in an inertial (unaccelerated) frame - eg. the road. In order for you to follow the car around the curve, a central force has to be applied to you. If you are going too fast for the friction on the seat to provide that force, you move until the car door provides it.

Centrifugal force is the apparent outward (centre fleeing) force that one feels as measured in the accelerating reference frame (ie the car moving around the curve). As measured in the inertial frame, there is no centrifugal force. There is just inertia and the centripetal force (toward centre).

a coin stays on a turntable because of friction. Part of the friction causes cicular motion. Which direction does the friction point?
Choices: a) foward along the coin's path. b)towards the center of the turntable. c)away from the center of the turntable. d)backward along hte coin's path

Which way does the coin have to accelerate in order to move in a circle? You have said that friction supplies that force. So what direction is the friction force?

AM

 

[wais]

?

Centripetal force is the force that pulls an object towards the center of its circular motion, while centrifugal force is the outward force that appears to push an object away from the center of its circular motion. In reality, centrifugal force is not a true force, but rather an apparent force that arises from the object's inertia wanting to continue in a straight line while the centripetal force keeps it in a circular path.

For the coin on a turntable, the friction points towards the center of the turntable. This is because the turntable is constantly pulling the coin towards the center in a circular motion, and the friction between the coin and the turntable surface resists this motion and creates the necessary centripetal force to keep the coin in its circular path.