To understand how the energy of the water differs between the two drops in river A (the waterfall) and river B (the hydroelectric dam), we can analyze the potential and kinetic energy at each location.
-
Potential Energy:
- The potential energy (PE) of water at the top of both drops is determined by its height above the base of the drop and is calculated using the formula PE = mgh (where m is mass, g is gravitational acceleration, and h is height). Since the drops in both rivers have the same height, the potential energy at the top of the drop would be the same in both cases.
-
Kinetic Energy:
- When the water falls, it converts its potential energy into kinetic energy (KE), which is calculated using KE = 1/2 mv^2 (where m is mass and v is velocity). The difference between the waterfall and the hydroelectric dam lies in how that kinetic energy is utilized:
- In river A (the waterfall), as water falls, it converts its potential energy into kinetic energy, leading to a high velocity at the bottom of the drop.
- In river B (the hydroelectric dam), the water flows through turbines that convert that kinetic energy into mechanical energy to generate electricity, which may result in a more controlled release of water and potentially lower velocity at the bottom compared to the waterfall.
- When the water falls, it converts its potential energy into kinetic energy (KE), which is calculated using KE = 1/2 mv^2 (where m is mass and v is velocity). The difference between the waterfall and the hydroelectric dam lies in how that kinetic energy is utilized:
Given these points, we can determine the following:
- The potential energy of the water would be the same at the top of the drop in both river A and river B.
- The kinetic energy of the water would likely be greater at the bottom of the drop in river A (the waterfall) due to the free fall and lack of energy loss to turbines compared to river B where the energy is converted to generate electricity.
Thus, the correct response would be:
The kinetic energy of the water would be greater at the bottom of the drop in the waterfall river A than at the hydroelectric dam in river B.