Question

23. Water coming out of horizontal pipe of Cross section with Speed v strikes a smooth vertical wall normally and rebounds with same speed. If density of water is d what is force on wall? (a) av^2 (b) 2av^2d (c) avd (d) 2avd 24. A stream of water flowing horizontally with a speed of 15ms^–1 gushes out of a tube of cross-sectional area 10^–2 m^2 and hits at a vertical wall nearby. What is the force exerted on the wall by the impact of water, assuming it doesn’t rebound. (a) 2250 N (b) 4500 N (c) 1250 N (d) 2500 N

Answer 1

Answer:

2250 is your answer ..............

Answer 2

Answer:

= 10^-2 m^2

# Solution-

Mass of water coming out of the pipe per second is calculated by,

dm/dt = A×v×ρ

dm/dt = 10^-2 × 15 × 1000

dm/dt = 150 kg/s

Here, water does not rebound, hence

Force = change in momentum per unit time

Force = dm/dt × v

Force = 150 × 15

Force = 2250 N

Force exerted on the wall will be 2250 N.

Explanation: