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The table shows the potential energy and kinetic energy of a skier at two different positions on a hill. Position and Energy Position (above ground) Kinetic Energy Potential Energy 100 meters 0 units 50,000 units 60 meters ? 30,000 units What is the kinetic energy of the skier at a height of 60 meters above ground? 20,000 units, because total energy remains unchanged 80,000 units, because total energy remains unchanged 20,000 units, because total energy of the skier decreases 80,000 units, because total energy of the skier decreases

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Answer:

To determine the kinetic energy of the skier at a height of 60 meters above the ground we need to understand the relationship between kinetic energy (KE) and potential energy (PE).

The total mechanical energy of the skier which includes both potential energy and kinetic energy remains the same at different positions on the hill as long as no external forces such as friction are acting on the skier. This is known as the conservation of mechanical energy.

The equation for total mechanical energy is:

Total energy = Kinetic energy + Potential energy

Let's substitute the given values into the equation for the first position where the skier is at 100 meters above the ground:

Total energy at 100 meters = 0 units (kinetic energy) + 50000 units (potential energy)

Total energy at 100 meters = 50000 units

According to the conservation of mechanical energy the total energy at the second position (60 meters above the ground) should be the same. So by substituting the given values into the equation we can solve for the kinetic energy at 60 meters:

Total energy at 60 meters = Kinetic energy at 60 meters + Potential energy at 60 meters

Total energy at 60 meters = Kinetic energy at 60 meters + 30000 units (potential energy)

Since the total energy remains the same we can write the equation as:

50000 units = Kinetic energy at 60 meters + 30000 units

Kinetic energy at 60 meters = 50000 units - 30000 units

Kinetic energy at 60 meters = 20000 units

Therefore the kinetic energy of the skier at a height of 60 meters above the ground is 20000 units.

User Stanislav Ivanov
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