College

A skier with a potential energy of [tex]$137,200 J$[/tex] waits on top of a ski jump that is 200 m high. What is the mass of the skier?

A. 20 kg
B. 70 kg
C. 137 kg
D. 686 kg

Answer :

To find the mass of the skier, we can use the formula for gravitational potential energy:

[tex]\[ \text{Potential Energy (PE)} = m \times g \times h \][/tex]

where:
- [tex]\( PE \)[/tex] is the potential energy, which is 137,200 Joules.
- [tex]\( m \)[/tex] is the mass of the skier, which we need to find.
- [tex]\( g \)[/tex] is the acceleration due to gravity, approximately 9.8 m/s².
- [tex]\( h \)[/tex] is the height, which is 200 meters.

We're given all the values except for the mass, so we'll rearrange the formula to solve for [tex]\( m \)[/tex]:

[tex]\[ m = \frac{PE}{g \times h} \][/tex]

Now, substitute the given values into the formula:

[tex]\[ m = \frac{137,200}{9.8 \times 200} \][/tex]

Simplify the calculation:

[tex]\[ m = \frac{137,200}{1,960} \][/tex]

[tex]\[ m \approx 70 \][/tex]

The mass of the skier is approximately 70 kg. Therefore, the correct answer is 70 kg.