00:01
We are given two different objects and we're comparing centrifugal force.
00:04
So the first one is a string with a ball being attached.
00:06
That's a string.
00:08
We're told the length of the string, which is also the radius of rotation, is 8 meters.
00:13
And we're told the tangential speed is 0 .8 meters per second.
00:19
And the centripetal force experienced is 0 .2 newtons.
00:23
And then we have a rope with a metallic object.
00:26
And the point of this problem is to find the mass of this object.
00:29
We're told the length of the rope, which is also the radius of rotation, is 2 .75 meters.
00:35
And we're given rotational speed, but in revolutions per second, we're told one revolution in 2 .9 seconds.
00:43
So how many radiance is that? that's 2 pi radiance in 2 .9 seconds.
00:48
And so when you multiply, then divide, you get 2 .17 radiance per second.
00:55
And we want to find the mass.
00:58
They also give us another little hint...