You swing a 2.2 kg stone in a circle of radius 75 cm. At what speed should you swing it so its centripetal acceleration will be 9.8 m/s^2

so if i do a=w^2 R....

and i plug everything in
so... 9.8 = w^2 (75)
9.8 (-75) = w^2
735 = w^2
Square root (735) and get 27.11

Is this correct cause the book gets 2.7 m/s do i need to move a decimal??

5 answers

... You swing a 2.2 kg stone in a circle of radius 75 cm.
Can you take it from here?
using the a = w^2 R... equation right

well R is going to = 75 cm and we are searching for w^2 so i would put 2.2 kg as A????

2.2 = w^2 (75)
No, mass has nothing to do with it.

9.8m/s^3=v^2/r
and r=.75 m
solve for v.
so... 9.8 = v^2 (.75)
9.8 (.75) = v^2
735 = v^2
Square root (7.35) and get 2.711
Excellent!