Now, take close notice: just as your profits will be magnified thanks to the margin, so are your losses. If the value of your position increases by 10%, it will increase by 10% of the POSITION value, not your required margin, i.e. 10% of $1,000 (=$100), not 10% of $50 (=$5).
Conversely, if your position loses that same 10%, you will need to set aside used margin of the leveraged value of the position, i.e. $100. Suddenly your equity has dropped far beyond your initial investment.
To ensure you do not enter a negative balance in such a volatile environment, your broker is required by law to send you a margin warning what a specified level and then close off positions to prevent a negative balance.