It requires extra power to go uphill, against the pull of gravity.
Going uphill takes more power than going on the flat, so unless you can add more power, you have to trade some speed for power to be able to go uphill.
Generally when we are going up hill because of the gravity pull, more power is needed. So when traveling uphill more power is needed than downhill.
Gravity.
check the air intake
Because it doesn't have enough power to pull itself. All vehicles slow down uphill if you don't feed them more fuel.
It loses power because going uphill is harder then going downhill therefore causing it to use more gas and then making it lose power bit by bit.
If it is an automatic transmission going uphill it will downshift to a lower gear for more torque.
because if you going down hill its faster because its a mountain
cool
you exert more energy going uphill because your muscles strain a bit more but it really depends on the angle
Gravity is trying to push the car down the hill. It takes more power to overcome that push of gravity. Unless you give the car more gas it will slow down.