A stream of water flowing horizontally with a speed of 15 m s - 1 gushes out of a tube of cross-sectional area 10 - 2 m 2 and hits a vertical wall nearby. The force exerted on the wall by the impact of water (assuming it does not rebound) is

Step-by-step solution

If the velocity of the stream be v (say) . In 1 second , the distance travelled = v . ∴ The volume of water hitting the wall per second, V = v a Where, a is the cross-sectional area. ⇒ V = 15 m / s × 10 - 2 m 2 [ ∴ Given, v = 15 m/s , a = 10 - 2 m 2 ] ⇒ V = 15 × 10 - 2 m 3 / s Mass of water hitting the wall per second, m = v o l u m e × D e n s i t y = 15 × 10 - 2 × 10 3 = 150 kg / s [ ∵ Density of water = 1000 kg / m 3 ] Initial momentum of the water hitting the wall per second = m × v = 150 × 15 = 2250 kg m / s 2