Answer:
The number of crates is 84580.
Explanation:
mass, m = 30 kg
height, h = 0.9 mm
Power, P = 0.5 hp = 0.5 x 746 W = 373 W
time, t = 1 minute = 60 s
Let the number of crates is n.
Power is given by the rate of doing work.

Compared to the charge on a proton, the amount of charge on an electron is same and has the opposite sign
<h3><u>Answer;</u></h3>
B. constant acceleration.
<h3><u>Explanation</u>;</h3>
- Free fall is the type of motion of a body or an object when only gravity is acting on it.
- <em><u>All objects undergo free fall on the earth surface at the same rate irrespective of their mass. This is because the gravitational field on the surface of the earth 9.8 N/kg, causes and acceleration equivalent to 9.8 m/s/s of any object in free fall motion.</u></em>
- Therefore,<u> the acceleration of any freely falling object near the surface of the earth is 9.8 m/s².</u>