Water runs out of a horizontal drainpipe at the rate of 135 kg/min. It falls 3.1 m to the ground. Assuming the water doesn't splash up, what average force does the water exert on the ground

The average force exerted by the water on the ground is 17.53 N.

Explanation:

Given;

mass flow rate of the water, m' = 135 kg/min

height of fall of the water, h = 3.1 m

the time taken for the water to fall to the ground;

mass of the water;

the average force exerted by the water on the ground;

F = mg

F = 1.789 x 9.8

F = 17.53 N

Therefore, the average force exerted by the water on the ground is 17.53 N.

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form