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A small dog is trained to jump straight up a distance of 1.2 m. How much kinetic energy does the 7.2-kg dog need to jump this high? (The acceleration due to gravity is 9.8 m/s².)

85 J
18.2 J
9.8 m/s
There is not enough information.

User Danikaze
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2 Answers

5 votes
The energy required to move some distance while experiencing a force is equal to the force times the distance. Force is equal to mass time acceleration.
formula is 7.2 * 9.8 * 1.2 = 84.67200
if we round of we get 85j
User Channel Cat
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6 votes

Answer;

85 joules

Explanation;

  • From conservation of energy, the kinetic energy at take off equals the potential energy at the top of the jump.
  • Potential energy = kinetic energy
  • Potential energy = mgh , where m is the mass, h is the vertical height and g is the gravitational acceleration.

Therefore; energy = 7.2 × 9.8 × 1.2

= 84.672 Joules

= 85 joules

Thus, the kinetic energy is 85 joules.

User Animekun
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8.5k points