T = (v-0)/a
t = (45.5)/(9.8)
= 4.64m/s.
hope this helps :)
For some reasons, no. If the driver looks focused and has experience, then it would be okay. Again, it could be dangerous if you bump into the truck, it would cause damage to you and your passengers.
Mostly, I would agree with 'No'. :)
The energy stored in motion is called kinetic energy.
