<span>If you spin fast enough, the impact of the glad will break the blade of grass before it can move out of the way. In the same way that if you kick an empty can, it will move out of the way, but if you shoot it with a gun, the bullet will cut through the can before it can move. Keep in mind a mower blade turns at probably 10,000 RPMs.</span>
To solve this problem we must keep in mind the concepts related to angular kinematic equations. For which the angular velocity is defined as

Where
Final angular velocity
Initial angular velocity
Angular acceleration
t= time
In this case we do not have a final angular velocity, then

Re-arrange for 



Therefore the mangitude of the angular aceleration is 5449.1rad/s²
<span>-(-(-)(-)(-10x))=-5 solve for x</span>
Initial velocity (u) = 0 m/s
Final velocity (v) = 25 m/s
time taken (t) = 10s
acceleration (a) = ?
Now,
Acceleration is rate of change of velocity, so formula is
a = (v - u)/t
a = (25 - 10)/10
a = 15/10
a = 1.5 m/(s^2)
Use this value of a.