Considering the definition of kinetic enery, the correct answer is the last option: the kinetic energy of the hammer is 1.72 m/s.
Kinetic energy is a form of energy. It is defined as the energy associated with bodies that are in motion and this energy depends on the mass and speed of the body.
Kinetic energy is defined as the amount of work necessary to accelerate a body of a certain mass and in a position of rest, until it reaches a certain speed. Once this point is reached, the amount of accumulated kinetic energy will remain the same unless there is a change in speed or the body returns to its resting state by applying a force.
Kinetic energy is represented by the following formula:
Ec = ½ mv²
Where Ec is kinetic energy, which is measured in Joules (J), m is mass measured in kilograms (kg), and v is velocity measured in meters over seconds (m/s).
In this case, you know:
Replacing;
Ec = ½ 0.55 kg×(2.5 m/s)²
Solving:
Ec=1.72 J
Finally, the correct answer is the last option: the kinetic energy of the hammer is 1.72 m/s.
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