The statement is false. Vectors are used to solve projectile motion problems because they allow the analysis of one direction at a time for two-dimensional motion. Scalar quantities can be used to analyze linear motion problem, but not projectile motion.
The gravitional potential energy, relative to the bottom of the giant drop, in joules, is (9800) times (the height of the drop in meters).
That's the PE of the empty car only, not counting any hapless screaming souls who may be trapped in it at that moment.
You should disconnect all wires from the circuit or make sure the switch is off or batteries are out
No, it will only melt if the temperature is lowered. If you compress it, it will change the shape, but it will not change the state it is in (i.e. solid).
