Non-Conservative forces acting on the book are , air resistance, sound and heat. The force acting on the book are gravityvela said:What forces act on the book? Are any non-conservative?
AJKing said:How far has the book traveled?
And what are the equations that tell you velocity under constant acceleration after a certain distance?
vela said:Sound and heat aren't forces. They don't push or pull on the book, right? Air resistance, however, is a force, but you can neglect it. So gravity is the only force acting on the book, and it's conservative. So you can use energy conservation. That means the energy at the initial point is equal to the energy at the final point.
What's the total mechanical energy at the initial point? You already found the potential energy there. What is the book's kinetic energy initially? Add the two together to find the total energy.
At the final point, the book is one meter off the floor. What does the total energy consist of there?
vela said:You got the potential energy at the end almost correct. You have the wrong units.
Energy conservation says that
\begin{align*}
E_i &= E_f \\
KE_i + PE_i &= KE_f + PE_f
\end{align*} So you have the potential energies. What are the kinetic energies?
Thanks bossvela said:No. You have a formula for kinetic energy. Use that. And there are two, one at the beginning and one at the end.
Kinetic energy is the energy an object possesses due to its motion. It is a type of energy that is associated with the movement of an object.
Kinetic energy is calculated by using the formula: KE = 1/2 * mass * velocity^2. This means that the kinetic energy of an object is directly proportional to its mass and the square of its velocity.
The SI unit for kinetic energy is joules (J). It can also be expressed in other units such as kilogram-meter squared per second squared (kg*m^2/s^2) or newton-meters (N*m).
Kinetic energy is the energy an object has due to its motion, while potential energy is the energy an object has due to its position or condition. Kinetic energy can be converted into potential energy and vice versa.
Some real-life examples of kinetic energy include a ball rolling down a hill, a car moving on the road, a person walking, or a satellite orbiting the Earth. Any object that is in motion has kinetic energy.