A roller coaster car is going 27 m/s when it reaches the base of a big drop. If it got all of its speed by rolling downhill, how high was the hill where the roller coaster started?

1 Answer
A08
Jan 29, 2018

Let the hill be #h# m high, #m# is mass of roller coaster car.
#:.# Potential energy at the top of hill#=mgh#
Using Law of conservation of energy all the Potential energy has been converted to car's Kinetic energy as it reaches the base of the big drop.
If #v# is cars velocity at the base of drop, equating PE to KE we get

#mgh=1/2mv^2#

Inserting given values and taking #g=9.81" ms"^-2#, we get

#9.81h=1/2(27)^2#
#=>h=(27)^2/(2xx9.81)=37.16" m"#, rounded to two decimal places

Related questions
Impact of this question
418 views around the world
You can reuse this answer
Creative Commons License