On a roller coaster<span>, </span>energy<span> changes from </span>potential<span>to </span>kinetic energy<span> and back again many times over the course of a ride. </span>Kinetic energy<span> is </span>energy<span> that an object has as a result of its motion. All moving objects possess </span>kinetic energy, which is determined by the mass and speed of the object.
List out all the variables that you do know;
acceleration=-9.8 ms⁻¹ (this remains constant on Earth)
Final velocity=?
Displacement (s)= -2.1 m
Initial Velocity(u)=2.5 ms⁻¹
v²=u²+2as
v²=(2.5)²+2(-9.8)(-2.1)
v²=47.41
v=√47.41
v=6.88549 ≈ 6.9 ms⁻¹
Hope I helped :)
