D as that's the only negative shown out of those choices.
Potential energy = mgh
So, energy gained
= mgh
= 70kg × (9.8m/s²) × 1000m
= 686000 kgm²/s²
= 686000 J
Answer:
No.1 projectile motion
No.2 a bullet being fired from a gun
No.3 5/m2
No.4 0/ms2
No.5 Uniform vertical motion
Answer:
Train wheels and rails are both made of steel, and the steel-steel friction coefficient is around 0.25. As a result, the stopping time and distance will be three to four times that of a car.