An ore car of mass 35000 kg starts from rest and rolls downhill on tracks from a mine. at the end of the tracks, 17 m lower vertically, is a horizontally situated spring with constant 5.3 × 105 n/m.

Explanation:

Given

mass of car

Vertical displacement

spring constant

Considering we need to find out compression in the spring when it reaches to ground

Here Gravitational potential Energy is converted to kinetic energy which finally converts to Elastic Potential Energy

suppose x is the compression in spring

Potential Energy=mgh

Elastic potential energy

what type of charge does it have? negative

object 2 because all the other ones are wrong