# Anyone good in Physics?

Best101
Posers and Puzzles 08 Dec '07 02:45
1. 08 Dec '07 02:45
I need some help with some formulas. Can someone tell me the formulas for finding Angular Velocity, and Tangental(SP?) Velocity?

These are for Circular Motion problems
2. coquette
08 Dec '07 06:22
I put into my search browser:

angular velocity physics

and hit on a lot of pages. this one was the second:

http://www.euclideanspace.com/physics/kinematics/angularvelocity/index.htm

3. Ramned
The Rams
08 Dec '07 13:08
Originally posted by Best101
I need some help with some formulas. Can someone tell me the formulas for finding Angular Velocity, and Tangental(SP?) Velocity?

These are for Circular Motion problems
Angular velocity and tangential velocity sometimes got confusing.
Ang v is the actual speed you go around the circle; tangential speed is the speed you are going tangential to the circle - for example if you swing a rock and let go, it flies off in a straight line TANGENTIAL to the circle with a tangential velocity.
4. Ramned
The Rams
08 Dec '07 13:18
A 40 kg child takes a ride on a ferris wheel that rotates 4 times / minute and has a radius of 8 m. (A) what is the centripetal acceleration of the child?

Ca = v^2 / r
- you know r
- you need to find the angular velocity: 4 revs/ 60 secs(in a minute) * (2 * pi * 9) (Circumference) = v.

(B) what force does the seat exert on the child at the lowest point of the ride?

Fnet = Fc + Fn. Note that the seat exerts a normal force upward. Fn is equal to mg. Fc is the center seeking force , m(v^2/r).

Fnet = m(v^2/r) + mg
Fnet = 40(v^2 / 9) + (40)(9.8) and solve (you figure v in part a).

(C)What force does the seat exert on the child at the highest point of the ride.

Fnet = mg - Fc (the normal force is now opposite of cf so they subtract...remember Fn = mg).

(D) what force does the seat exert on the child halfway between the top and bottom of the circle.

Now, Fc is pointing to the right towards the center while Fn is still pointing up, forming a right triangle. You must use pythagorean to find the resultant.

Fnet^2 = Fn^2 + Fc^2.
5. AThousandYoung
No1GaveAF*IWasWhite
20 Dec '07 06:39
Originally posted by Ramned
Angular velocity and tangential velocity sometimes got confusing.
Ang v is the actual speed you go around the circle; tangential speed is the speed you are going tangential to the circle - for example if you swing a rock and let go, it flies off in a straight line TANGENTIAL to the circle with a tangential velocity.
Angular velocity is measured in degrees or radians per unit of time; tangential velocity is distance per time.
6. wolfgang59
Mr. Wolf
20 Dec '07 12:48
An object's tangential velocity IS its velocity, which being a vector quantity is constantly changing. When the string breaks on that rock you are swinging around your head it flies off with that velocity.
7. 29 Jan '08 03:13
Originally posted by Best101
I need some help with some formulas. Can someone tell me the formulas for finding Angular Velocity, and Tangental(SP?) Velocity?

These are for Circular Motion problems
e=mc2
8. 31 Jan '08 03:23
Originally posted by wolfgang59
An object's tangential velocity IS its velocity, which being a vector quantity is constantly changing. When the string breaks on that rock you are swinging around your head it flies off with that velocity.
tangential velocity is a vector quantity, but since its direction is always tangent to its position in the circular path it travels, is it at all useful to consider tangential speed (the magnitude of tangential velocity)? i'm not much of a physics guy, just sort of mathematically musing...