Can somebody explain the usage of leverage in trading

if i buy a stock at 50 rs using leverge and it moves to 55 rs… stocks dnt move in a singular direction. in reaching the taget of 55 when can my broker demand extra margin fm me?when the stock dips at 54 rs or in another case…when it moves to 52 rs first then dips to 51 rs and then shoots to 55 rs…?the broker incurs a loss only when the price dips below 50(purchase price)if brokers starts demanding margin for every dip in share price… trading using leverage wd become impossible…

When your order is placed the amount required will be blocked from your account.

the money you lost from your trade will be reduced from your account when your trade is done.