Adentist causes the bit of a high-speed drill to accelerate from an angular speed of 1.50 × 10 4 1.50×104 rad/s to an angular speed of 3.35 × 10 4 3.35×104 rad/s. in the process, the bit turns through 2.02 × 10 4 2.02×104 rad. assuming a constant angular acceleration, how long would it take the bit to reach its maximum speed of 6.90 × 10 4 6.90×104 rad/s, starting from rest?

0.32 s

Explanation:

Initial angular speed:

Final angular speed:

Angular rotation:

The angular acceleration of the drill can be found by using the equation:

Re-arranging it, we find , the angular acceleration:

Now we want to know the time t the drill takes to accelerate from

to

This can be found by using the equation

where is the angular acceleration we found previously. Solving for t,