What are some indicators of energy transformations?

Explanation:

But you can experience many indicators of energy transformations with your five senses—touch, sight, hearing, taste, and smell. The simplest example is when you observe through sight that something has started to move. Energy is always being transformed when an object speeds up or slows down.

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adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.