yes they will turn freely in neutral but still kind of hard to turn due to rear end gears.
you should raise the rpm of the motor (not too much though) and when at the light, put the car in neutral. this reduces the drivetrain resistance, allowing the motor to spin more freely
Provided the heater is of a low wattage it should not affect normal running of the car
The car's differential gear will transfer power equally to both drive wheels, and if one has no friction at all (sand, water, or not touching ground) it will spin freely. In loose mud or water, both wheels will spin.
It depends on your car, but should be very obvious.
How long it takes a car heater to warm up depends on the temperature outside. In cold weather the heater can take several minutes to warm up.
Heater core is probally leaking. Should be located under dash on passenger side.
check to make sure the belt tensioner is functional if not it needs to be replaced
Do you mean where on a car is a block heater install or who do you take the car to to install?
in a spin or a slide in vehicle you should turn into the slide so if car is sliding to the left,steer to the left oversteer and you will slide or spin the other way causing what is called fish tailing might also take your foot off the gas,BUT do not hit the brakes
Kinetic Energy helps the car wheel spin...
If your asking about a heater core for a car. you pretty much have to pull the engine to get at it. as it is part of the system, it should get flushed out when you flush the system.