Answer:
12. 7500 J
gpe = mxgxh
gpe = 150x10x5
= 7500
13. 7500 J
gpe = 2.5x10x300
= 7500
14.
gpe = ke
ke = ½mv²
ke of object 1 = ½x2x2²
ke of 1 = 4
so object 1 has a potential energy of 4 J
ke of object 2 = ½x4x3²
ke of 2 = 18
object 2 has a potential energy of 18 J
15. The person at the top of the stairs has the most potential energy as the greater your distance from the ground (height) the greater your potential energy.
16. The motorbike has a greater KE as it has a higher velocity.