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Someone edges the brick off the roof, and it begins to fall. What is the brick’s kinetic energy when it is 35 ft above street level?

User LShi
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The kinetic energy of the brick when it is 35 ft above street level is equal to the potential energy, which is 105.156 J.

Kinetic energy is the energy possessed by an object due to its motion. It is given by the formula KE = 0.5 * mass * velocity^2. To calculate the kinetic energy when the brick is 35 ft above street level, we need to first convert the height to meters. 35 ft is approximately 10.67 m.

The potential energy at this height is given by PE = mass * g * height, where g is the acceleration due to gravity (9.8 m/s^2).

Once we have the potential energy, we can use the principle of conservation of energy to determine that the kinetic energy at this height is equal to the potential energy.

Therefore, the kinetic energy of the brick when it is 35 ft above street level is equal to the potential energy, which is PE = 1 kg * 9.8 m/s^2 * 10.67 m = 105.156 J.

User Joseph Combs
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