Because Mars is further from the sun than Earth is, thus the gravitational pull is not as great on Mars as it is on Earth, making us lighter :)
The watts determine the brightness. Watt is the unit of Power. And Power is equal to Voltage x Amps (current). So both the current and voltage determine the brightness.
Answer:
How fast is it going? 29.4 Meters per second
How far has it fallen? 44.1 meters
Explanation: Gravitional Acceleration: 9.8 meters per secnd squared!