Suppose that the nozzle of a fire hose emits a stream of water at a velocity of 30m/s and
a rate of 10kg/s. Assuming that the water in the hose is moving at 10m/s, how much force
does the nozzle exert on the fireman who is holding it?
(A) 300N.
(B) 200N.
(C) 0.
(D) 100N.
Suppose that the nozzle of a fire hose emits a stream of water at a velocity of 30m/s and
a rate of 10kg/s. Assuming that the water in the hose is moving at 10m/s, how much force
does the nozzle exert on the fireman who is holding it?
(A) 300N. --- No.
The change in velocity is 30-10m/s.
Suppose that the nozzle of a fire hose emits a stream of water at a velocity of 30m/s and
a rate of 10kg/s. Assuming that the water in the hose is moving at 10m/s, how much force
does the nozzle exert on the fireman who is holding it?
(B) 200N. --- Yes.
The nozzle exerts 200N on the water, so the water exerts 200N on the nozzle. The fireman must exert
200N on the nozzle to keep it in equilibrium, so the nozzle exerts 200N on the fireman.
Check the other answers.
Questions
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What this question is about
18.4
Suppose that the nozzle of a fire hose emits a stream of water at a velocity of 30m/s and
a rate of 10kg/s. Assuming that the water in the hose is moving at 10m/s, how much force
does the nozzle exert on the fireman who is holding it?
(C) 0. --- No.
Obviously you have never held a firehose.
Suppose that the nozzle of a fire hose emits a stream of water at a velocity of 30m/s and
a rate of 10kg/s. Assuming that the water in the hose is moving at 10m/s, how much force
does the nozzle exert on the fireman who is holding it?
(D) 100N. --- No.
The velocity change is 30-10m/s.