I am having NiCd batery of 700mAh and also by mistake i purchased NiMH baterry charger. Can i use NiMh charger for charging NiCd baterry.
No, you shouldn't do that.
Don't mix batteries, it's not safe, I personally wouldn't recommend it on the occasion that it may explode and get battery acid all over you and burn you, or you can still try it at your own risk. Try exchanging it or returning it and buying another one, the store would understand.
NiMH batteries are designed for rapid recharging. The same charge current applied to a nicad could easily cause over-heating. Some chargers adapt to either system with a switch, but it appears yours doesn't, so don't. Same goes for using it with non-rechargables, the high charge current will cause fire or explosion.
No. The chemistry of the battery is different and you will damage a NiCad by charging it in a NiMH charger. Some chargers are 'smart chargers' and can charge either. Check and make sure your charger isn't a smart charger. If not, maybe you can take it back and get the right charger.
