If a rock is thrown in the air, when will it have the greatest potential energy?
I'm thinking the answer is at the highest point because it slows and is just about to head down and accelerate, am I right?
Yes, you are correct. The greatest potential energy of the rock will be at the highest point of its trajectory when it is just about to start descending. At that point, the rock has gained the maximum height and its velocity becomes zero before it starts accelerating downward due to gravity.
Yes, you are correct. The greatest potential energy of a rock thrown in the air occurs at its highest point in the trajectory. As the rock is thrown upwards, it gains potential energy due to its vertical displacement from the ground. At the highest point, the rock has reached its maximum height and possesses the maximum potential energy. At this point, the rock is momentarily at rest before it starts falling back down due to the force of gravity.
Yes, you are correct! The rock will have the greatest potential energy at the highest point of its trajectory when it is just about to change direction and start moving downward. At this point, the rock's velocity is at its minimum, as it momentarily comes to a stop before beginning its descent. As potential energy is dependent on both the height and the mass of an object, the rock will have its maximum potential energy when it is at its highest position in the air.
To calculate the potential energy at any given point, you can use the formula:
Potential Energy = mass × acceleration due to gravity × height
where mass is the mass of the rock, acceleration due to gravity is a constant (approximately 9.8 m/s^2 on Earth), and height is the vertical distance between the rock's position and a reference point (such as the ground).
However, in this specific scenario, you don't need to perform any calculations as the concept of potential energy changing along with the rock's motion is intuitive.