Depending on the construction of your house, you may actually be hearing the water making its way down the drain line. I can hear it in my house sometimes. You may hear it while you're making your "contribution" because as water is added to the bowl, an equal amount is flowing over the trap and down the drain. The same happens after a flush, while the tank is filling. A certain amount of water is being diverted into the bowl to refill it, and once it's full, the excess dribbles down the drain. You're problably hearing it hit the elbow where the pipe goes from vertical to horizontal. Another answer to the problem is that the water from the tank is leaking through the flapper and the flapper needs to be replaced. If you replace the flapper then you need to have a peice of course Wet or dry sandpaper to smooth out the hole that the flapper closes over.
water is turned off ??
Usually not. If toilet has a mixing valve going to it so warm water fills toilet tank and toilet runs constantly, then enough warm water could leak out through toilet to possibly have an effect on water heater.
Depends on how bad it is leaking
Because the flapper is stuck.
check that the toilet stopper has been switched on and check that the strainer inside the toilet inlet is clear of debris
By taking shorter showers and not flushing the toilet
If it is just the toilet that doesn't have water, then the pipes are probably not frozen. If it is the whole house than maybe yes. If you have water at other faucets, look at the toilet and see where the blockage is. Disconnect the supply line under the tank and see if water is coming through the shut off at the toilet if there is one.
It's possible for the running water to wash it, but so would a kitchen faucet
no. repair or adjust your water level valve.
you should try to look in the back of the toilet and search for any clogs in there while you flush it. if that isn't the problem then i don't know what it is
the flapper in tank is not sealing after flush.change flapper.
Sounds like the flap that allows water to enter the bowl from the tank, isn't sealing. If this is true, the water will be constantly running.
Each flush of a toilet uses the same amount of water.