Saturday

April 19, 2014

April 19, 2014

Posted by **Steph** on Friday, November 26, 2010 at 5:02pm.

A) What is the magnitudes of the rock's angular acceleration at t=1.60 s?

B) At what time is the magnitude of the rock's acceleration equal to g? (Remember that you need to include both tangential and radial accelerations in computing the magnitude of the rock's acceleration.)

- physics -
**Damon**, Friday, November 26, 2010 at 5:21pmwr = v

a = r dw/dt

1.4 = r dw/dt

dw/dt = angular acceleration = 1.4/r = 2.8/.57

assume constant angular deacceleration

radial acceleration = w^2 r

tangential acceleration = r dw/dt

(we know dw/dt from above)

w r = v = 3 m/s at t = 0

wo = 3/r

w = wo - (dw/dt)t

that gives you w^2 r as a function of time

so when is

(w^2 r )^2 + (r dw/dt)^2 = 9.8^2 ?

- physics -
**Anonymous**, Monday, November 21, 2011 at 11:08pmbig dicks.

- physics -
**...**, Monday, November 28, 2011 at 4:45amwhy does damons answer have to make no sense -_- im sure its right but its so confusing the way its written

**Related Questions**

physics - A rock stuck in the tread of a 57.0 cm diameter bicycle wheel has a ...

Physics - A rock stuck in the tread of a 50.0 cm diameter bicycle wheel has a ...

Physics - A rock stuck in the tread of a 50.0 cm diameter bicycle wheel has a ...

phys - A rock stuck in the tread of a 56.0--diameter bicycle wheel has a ...

Angular Acceleration - A rock stuck in the tread of a 50.0 cm diameter bicycle ...

physics - A bicycle wheel has a diameter of 57.7 cm and a mass of 2.66 kg. The ...

physics - A wheel of radius 0.5 m rotates with a constant angular speed about an...

physics - A bicycle wheel has a diameter of 64.2 cm and a mass of 1.79 kg. ...

physics - If the rotational speed of each wheel is 9 revolution per second, what...

physics - If the rotational speed of each wheel is 9 revolution per second, what...