Why does descending a long grade increase overall stopping distance compared to flat ground at the same speed?

Pick an answer

1. Grade only affects steering, never braking distance
2. Going downhill actually shortens stopping distance, since gravity assists the brakes and adds extra stopping force
3. Stopping distance is not affected by grade at all, only by the vehicle's speed
4. Gravity is adding to the vehicle's momentum going downhill, so the brakes have to work against both speed and the pull of the grade

Correct!

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