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At the top of a hill that is 4.37 meters high, a 70 kg skate boarder has 3000 1 point

joules of potential energy. What is his speed at the bottom of the hill where
his potential energy is zero?

User SuperJMN
by
4.8k points

1 Answer

1 vote

Answer:

9.26m/s

Step-by-step explanation:

Given parameters:

Height of the hill = 4.37m

Mass of skate boarder = 70kg

Potential energy = 3000J

Unknown:

Speed at the bottom of the hill = ?

Solution:

At the bottom of the hill, the total potential energy is the same as the kinetic energy.

Potential energy = Kinetic energy

mgh =
(1)/(2)mv²

2mgh = mv²

v² = 2gh

v = √2gh

g is the acceleration due to gravity

h is the height

v = √2 x 9.8 x 4.37 = 9.26m/s

User Krishna Kamal
by
4.5k points