Final answer:
A fan is the object that transforms electrical energy into energy of motion (mechanical energy) by using an electric motor to spin the fan blades.
Step-by-step explanation:
The student has asked which object is transforming electrical energy into energy of motion, also known as mechanical energy. The devices listed are a fan, a speaker, a light cooktop, and a general reference to an iStock 2018 photo.
The electric motor within the fan converts electrical energy into mechanical energy, which results in the rotation of the fan blades and the consequent movement of air. This transforming of electrical energy into mechanical energy is not seen in speakers, which convert electrical energy into sound energy, or light cooktops, which convert electrical energy into heat.
An electric motor is a device that executes this type of energy transformation efficiently. Hence, a fan is the correct answer as it uses an electric motor to convert electrical energy into kinetic energy – the energy of movement.