Nothing wrong with this. They probably wanted just the magnitude of that work.PhizKid said:
You forgot about the friction.
Looks like they used the 3 m distance by mistake.PhizKid said:
Initial mechanical energy + work done by friction = Final mechanical energy
I agree with your answer. Even using their incorrect value for the work done by friction you won't get their answer.PhizKid said:
Work is defined as the transfer of energy that occurs when a force is applied to an object and the object moves in the same direction as the force.
Potential energy is the energy that an object has due to its position or state. It is the energy that can be converted into other forms of energy, such as kinetic energy.
Kinetic energy is the energy an object possesses due to its motion. It is directly proportional to the mass of the object and the square of its velocity.
Potential and kinetic energy are forms of energy that can be converted into each other. When an object is at rest, it has potential energy, and when it is in motion, it has kinetic energy. The total energy of an object is the sum of its potential and kinetic energy.
Understanding these concepts can help in various ways, such as in designing efficient machines, calculating the amount of energy needed for certain tasks, and understanding the behavior of objects in motion. It also helps in understanding and solving real-life problems related to energy and its conservation.