Explain, why is it difficult for a fireman to hold a hose, which ejects large amount of water at a high velocity?

Explanation

When a fire hose pipe ejects large amounts of water in the forward direction at a high velocity, then the forward going stream of water exerts a backyard reaction force due to which the hose pipe tends to go backward and slips from the hands of fireman. This backward movement of hose pipe make it difficult for a fireman to hold the hose pipe. And the fireman has to hold the hose pipe strongly.