A 0.5 kg object is initially at rest on a frictionless surface at a height of 2 meters above the ground. The object is then released and falls freely to the ground.
a) Calculate the potential energy of the object when it is at rest.
b) Determine the kinetic energy of the object when it reaches the ground.
Assume g = 9.8 m/s².
Remember to show all your work and include units in your final answers.
a) To calculate the potential energy of the object, we can use the formula:
Potential Energy = mass * gravity * height
Plugging in the given values:
Potential Energy = 0.5 kg * 9.8 m/s² * 2 m
Potential Energy = 9.8 Joules
Therefore, the potential energy of the object when it's at rest is 9.8 Joules.
b) When the object reaches the ground, all its potential energy is converted into kinetic energy. The formula for kinetic energy is:
Kinetic Energy = 0.5 * mass * velocity²
Initially, the object is at rest, so its velocity is zero. Therefore, the final velocity is also zero when it reaches the ground. Hence, the kinetic energy will also be zero.
Thus, the kinetic energy of the object when it reaches the ground is zero Joules.
Note: The potential energy is converted entirely into kinetic energy due to the conservation of energy principle.