Awheel starts from rest and rotates with a constant angular acceleration about a fixed axis. it completes the first revolution 6.0 s after it started. how long after it started will the wheel complete the second revolution?

After 8.5 s

Explanation:

We can use the equivalent suvat equation for rotational motions to find the angular acceleration of the wheel:

where:

is the angular displacement covered during the first 6.0 s (the angle corresponding to one revolution)

is the initial angular velocity

is the angular acceleration

t = 6.0 s is the time

Solving for  ,

Now we want to find instead the time t after which the wheel has completed two revolutions, so the time t at which

Using again the same equation as before and solving for t, we find: