Question

Water from a fire hose is directed horizontally against a wall at a rate of 69.4 kg/s and a speed of 19.6 m/s. Calculate the magnitude of the force exerted on the wall, assuming the water comes to a complete stop when hitting the car, with no splash-back.

Answer 1

Force, |F| = 1360.24 N

Step-by-step explanation:

It is given that,

Water from a fire hose is directed horizontally against a wall at a rate of 69.4 kg/s,
`(m)/(t)=69.4\ kg/s`

Initial speed of the water, u = 19.6 m/s

Finally water comes to stop, v = 0

To find,

The magnitude of the force exerted on the wall.

Solution,

Let F is the force exerted on the wall. The product of mass and acceleration is called the force exerted. Using second law of motion to find it as :

`F=m(v-u)/(t)`

`F=(-mu)/(t)`

`F=-69.4\ kg/s* 19.6\ m/s`

|F| = 1360.24 N

So, the magnitude of the force exerted on the wall is 1360.24 N.