Question

A 61 kg skier starts from rest at the top of a 1200 m long trail which drops a total of 227 m from top to bottom. At the bottom, the skier is moving 11 m/s. How much energy was dissipated by friction?

Answer 1

energy dissipated = 132 kJ

Step-by-step explanation:

mass = 61 kg

height drop = 227 m

velocity = 11 m/s

potential energy due to height drop from top to bottom

P.E. = m g h

P.E. = 61× 9.8× 227

P.E. = 135,700 J

kinetic energy =
`(1)/(2)mv^2`

=
`(1)/(2)* 61 * 11^2`

= 3690.5 J

energy dissipated = P.E - K.E.

= 135,700 J -3690.5 J

=132,009.5 J = 132 kJ