1) In a two-dimensional tug-of-war, Alex, Betty, and Charles pull horizontally on an automobile tire at the angles shown in the picture. The tire remains stationary in spite of the three pulls. Alex pulls with force FA of magnitude 207 N, and Charles pulls with force FC of magnitude 188 N. Note that the direction of FC is not given. What is the magnitude of Betty's force FB if Charles pulls in (a) the direction drawn in the picture or (b) the other possible direction for equilibrium?
For a, I got 291 N as my answer and it's correct, but I don't know how to get to b.
2) At t1 = 5.00 s, the acceleration of a particle moving at constant speed in counterclockwise circular motion is
a1=(8.00m/s^2)i+(6.00m/s^2)j
At t2 = 6.00 s (less than one period later), the acceleration is
a2=(6.00m/s^2)i-(8.00m/s^2)j
The period is more than 1.00 s. What is the radius of the circle?
I have done this problem over and over and I keep getting 9.12 m, but I know it's wrong.
3 answers