Question

it is difficult for a Fireman to hold hose give reason

Answer 1

Yup Yup

You just have to remember Newton's third law. Water leaves the hose and great pressure (to reach far), and area of hose is less ( increases the pressure P=F/A inverse relation). So basically hose pushes the water with considerable force (F= PA).

And the water pushes the hose back! (Newton said so)

You can try it at home, take you garden pipe. And turn it on. But your pipe is a little sort , so you can't reach you plants.

Now what do you do to increase the range of water?

You SQUEEZE the opening, reducing the area, increasing the pressure. You will feel the pipe pushing your hand back.

Or just leave you pipe be, it will swirl like a snake! To calm it down, you need force.

'Nough said.

Hope this helped