To understand how mechanical energy is converted into electrical energy, we need to consider the principle of electromagnetic induction. This principle is the basis for the operation of generators. A generator works by rotating a coil within a magnetic field, which induces an electric current in the coil as per Faraday's law of electromagnetic induction. This process transforms mechanical energy into electrical energy.
Let's analyze the options given:
- Motors: Motors do the reverse process; they convert electrical energy into mechanical energy.
- Electric Geysers: These devices convert electrical energy into thermal energy for heating water.
- Generators: Generators are specifically designed to convert mechanical energy into electrical energy using the process of electromagnetic induction. Hence, this option is correct.
- Televisions: Televisions convert electrical energy into light and sound energy, allowing viewers to watch and listen to content.
Therefore, the correct answer is generators, as they are the devices that efficiently convert mechanical energy into electrical energy.