First....What
is torque?:
Torque is a twisting force- (it doesn't do any 'work' itself- it
is simple an application of energy).
Work (or 'stuff') happens, when torque is applied and movement occurs.
This motor shaft will make 3 rotations, in the same time the output
shaft makes 5
Gears used: 20 tooth on motor, 12 tooth on output
Gear Ratio: 3:5
Power: 3/5x motor
Speed: 5/3x motor (faster)
This motor shaft will make 1 rotations, in the same time the output
shaft makes 3
Gears used: 24 tooth on motor, 8 tooth on output
Gear Ratio: 1:3
Power: 1/3x motor
Speed: 3x motor (faster)
This is probably the best for speed and power(torque). The robot would be front wheel drive based on that if the nxt is on the back with the wheels the robot would flip or slide down due to the weight on the downhill side of the robot not the uphill side(assuming the track is at 22.5 degress