A machinist turns on the power to a grinding wheel at time t = 0 ...

[azncindy619]

A machinist turns on the power to a grinding wheel at time t = 0 s. The wheel accelerates uniformly from rest for 10 s and reaches the operating angular speed of The wheel is run at that angular speed for 30 s and then power is shut off.
 
  The wheel slows down uniformly at 2.1 rad/s2 until the wheel stops. In this situation, what is the angular acceleration of the wheel between t = 0 and t = 10s? A) 3.8 rad/
  B) 4.6 rad/
  C) 5.3 rad/
  D) 6.1 rad/
  E) 6.8 rad/

Question 2

Physically, the type of energy represented by the water behind a dam is
 
  A) kinetic.
  B) thermal.
  C) chemical.
  D) electromagnetic.
  E) gravitational.

[Sierray]

Answer to Question 1

A

Answer to Question 2

E

[azncindy619]

Thanks for the timely response, appreciate it

[Liddy]

Gracias!