Using regenerative brakes: Engineers designing a braking system for an electric car want  to test the current that the system generates. They drive a car which is fitted with this braking system at different speeds, brake,then measure the voltage generated.Identify the independent and dependent variables in this experiment.Formulate a research question.Predict a suitable hypothesis for the experiment supported by scientific reasoning.

In this experiment, the independent variable is the speed at which the car is driven before braking. This is because the engineers are controlling this variable - they decide at what speed to drive the car.

The dependent variable is the voltage generated by the braking system. This is the variable that the engineers are measuring - it depends on the speed at which the car is driven.

A possible research question could be: "How does the speed at which an electric car is driven affect the voltage generated by its regenerative braking system?"

A suitable hypothesis for this experiment could be: "The higher the speed at which the car is driven, the greater the voltage generated by the regenerative braking system." This hypothesis is based on the principle of regenerative braking, which converts the kinetic energy of the car (which increases with speed) into electrical energy. Therefore, it is reasonable to predict that driving the car at higher speeds will generate more electrical energy, and thus a higher voltage.