Answer:

Explanation:
It is given that,
Mass of the grindstone, m = 3 kg
Radius of the grindstone, r = 8 cm = 0.08 m
Initial speed of the grindstone, 
Finally it shuts off, 
Time taken, t = 10 s
Let
is the angular acceleration of the grindstone. Using the formula of rotational kinematics as :



Let
is the number of revolutions of the grindstone after the power is shut off. Now using the third equation of rotational kinematics as :





or

So, the number of revolutions of the grindstone after the power is shut off is 50.
64 miles/hour
Therefore 1/64 hours/mile
68 miles * 1/64 hours/mile (notice how miles cancels out)
Therefore the answer is 68/64 hours = 1.0625 hours = 1 hour 3min and 45sec.
That's false. Mechanical waves (like sound and ocean waves) do
need a medium to travel in, but electromagnetic waves (like radio
and light) don't.
A pH scale goes from 0 - 14.
7 is in the middle so it is neutral