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2 years ago

7. A 78-kg skydiver has a speed of 62 m/s at an altitude of 870 m above the ground.

1 answer:

8 0

The kinetic energy, potential energy and total mechanical energy possessed by the skydriver are 1.5 × 10⁵ Joule, 6.7 × 10⁵ Joule and 8.2 × 10⁵ Joule respectively.

To find the answer, we need to know about the expression of kinetic energy and potential energy.

<h3>What are the expressions of kinetic energy and potential energy?</h3>

Mathematically, kinetic energy= 1/2 × mass × velocity²
Gravitational potential energy near the earth surface= mass × g × height on the earth surface

<h3>What's the kinetic energy, potential energy and total mechanical energy of the 78kg skydriver at 870 m on earth surface with 62 m/s velocity?</h3>

Kinetic energy= 1/2 × 78 × 62² = 1.5 × 10⁵ Joule
Potential energy= 78×9.8×870= 6.7× 10⁵ Joule

<h3>What's the total mechanical energy?</h3>

Mechanical energy= kinetic energy+ potential energy
1.5 × 10⁵ Joule + 6.7× 10⁵ Joule = 8.2× 10⁵ Joule

Thus, we can conclude that the kinetic energy, potential energy and total mechanical energy possessed by the skydriver are 1.5 × 10⁵ Joule, 6.7 × 10⁵ Joule and 8.2 × 10⁵ Joule respectively.

Learn more about the kinetic energy, potential energy and mechanical energy here:

brainly.com/question/17051553

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