Question

give reason and give the law to thse statements

(A) it is easier to push an empty box than the box full of books

(B) it is difficult for a fireman th hold a hose which ejects large amount of water with high velocity

Answer 1

a) It's more difficult to push a box full of books than an empty box because the mass of box full of books is larger and results in larger frictional force ( μ mg )

b) it's difficult for a fireman to hold a hose which ejects large amount of water with high velocity because the change of momentum of fluid exiting exerts a backward force on the hose pipe which is held by the fireman