Please be more specific....simply replacing the breaker with a 20 amp may cause a fire; if the cable is sized for 15 amp and is overloaded. Your 15 amp breaker is probably feeding #14 wire. The use of a 20 amp breaker requires at least a #12 wire be used. Fire hazard if breakers and wiring are not sized correctly.
No. The purpose of an amplifier circuit is to convert a weak signal into a stronger signal; this requires electrical energy.
The circuit element whose purpose is to convert electrical energy into another form of energy is the
The job of the bulb in a circuit is to convert electrical energy to light. It's called the load in the circuit.
Bulbs convert an electrical energy to produce light
I assume you mean electricity not energy. The electrical energy doesn't leave the circuit as such it is converted by a component. E.G. A bulb in a circuit will convert the electrical energy into light and some heat.
The function of an electric motor is to convert electrical energy to mechanical energy for the purpose of doing work.
That will convert the electrical energy into heat energy. Charge is not converted to anything; charge is maintained. What you are describing is called "resistance".
A motor does not provide energy. It converts electrical energy to mechanical energy. From a circuit standpoint, the motor is considered a load (similar to a resistor). Resistors convert electrical energy to heat energy.