Most Important Selected Qs for JEE AdvancedPhysicsMechanical Properties of Fluids
Water is filled in a uniform container of area of cross section A . A hole of cross section area a( A) is made to the wall of container at a height of 20 m above the base. Water streams out and hits a small block placed at some distance from container. With what speed (in ms ⁻¹ ) should the block be moved such that water stream always hits the block before the level of water in the vessel reaches 20 ~m . ( . Given .
Correct answer
1
Step-by-step solution
Velocity of efflux v= 2 g y Range x= 2 g y 2 h g The velocity of the block must be ( d x d t ) . V_b= d x d t = 2 h g 2 g 1 2 y d y d t V_b= h y d y d t .( i ) Using equation of continuity A d y d t =a 2 g y .......(ii) equation (i) and (ii) V_b= h y a A 2 g y V_b= 2 g h a A =20 1 20 =1 ~ms ⁻¹ .