00:01
Hi, here in this given problem there are three different questions based upon circular motion.
00:07
In the first one, initial angular velocity of the wheel, let it be represented as omega -i.
00:15
This is given as 6 .75 radian per second, angular acceleration, alpha.
00:26
This is 2 .0 radian per second square.
00:32
Now, the final angular velocity is not given directly.
00:40
It is given in terms of revolutions per minute.
00:44
So for final angular velocity, rate of rotation is 1 rpm.
00:57
Or we can say 1 by 60 revolutions per second so final angular velocity will be given by omega f that is 2 pi into f means this is 2 pi by 60 radian per second or we can say this is it is calculated to be equal to 0 .105 radian per second means the angular velocity is reducing.
01:29
So this acceleration, angular acceleration, actually it should be retardation in negative.
01:36
So using first equation of motion, omega f is equal to omega i plus alpha t.
01:46
So this is 0 .105 is equal to omega i, 6 .75 for alpha minus 2 .0 into t, which we have to and finally this time is calculated to be equal to 3 .3 second.
02:07
Answer for this first problem here.
02:10
And this is the first option which is correct here...