Sure, that's how the sport started. Don't expect to be able to go as fast, or to drop as high as the riders on full sus bikes though.
Sam Hill
When you're braking hard, trying to climb a steep hill or turning hard.
If you pedal very fast then you may lose control
it depends on how on how fast you petal and how fit you are
Yes, there are four basic types of mountain bikes. There are cross-country, all-mountain, free-ride, and down-hill mountain bikes. All-mountain is the recommended mountain bike for rocky terrain.
find a DH bike and ride down a DH track signal hill is a good place to start! (dunedin, NZ)
A hill is hard to get up and a pill is hard to get down
The duration of The Englishman Who Went Up a Hill But Came Down a Mountain is 1.65 hours.
Cycle down a hill.
Coasting.
Momentum is the product of mass and velocity which infers motion taking place. If the bike was moving then yes it would make it go downhill. The real culprit would be gravity if the bike was not already in motion. The hill is an incline and the bike is being pulled by gravity down that incline.
Same reason as walking up stairs is hard - you have to overcome gravity.