00:01
This problem has been given that there is a wheel and with respect to the wheel, there is a torque of 72 newton's meter that's acted upon this wheel, provided that the moment of inertia of this wheel is 162 kilograms meter square.
00:20
And we have to determine that as the wheel starts from rest, how much time will it take in order to make 26 complete revolutions? here we know that one revolution it accounts for two pi angular displacements covered so for 26 revolutions the angular displacement that this wheel would have gone through will be 26 times 2 pi that's 52 pi radiance so that becomes the angular displacement which is 52 pi radiance and we have to determine the time provided that the initial angular velocity was zero radiance per second and from this value of the torque and moment of inertia, we can compute the angular acceleration.
01:07
So according to the relation torque equals i times alpha, where alpha is the angular acceleration, we can get the angular acceleration by dividing the torque with the value of moment of inertia.
01:20
And when we divide 72 with 162, we can get the angular acceleration as 0 .44 radiance per second square approximately.
01:30
So we take this value of angular acceleration and we relate all these parameters that we have here.
01:37
So according to the expression, theta equals omega -not t plus half alpha t square.
01:44
Let's use this equation and put the values that we have here...