1) When a 12 volt car battery is short circuited with a wire, the current drawn from the battery is 100 amperes. The resistance of the wire is:

2) A battery operating a large flashlight produces a current of 0.6 amperes in a light bulb that has a resistance of 4 ohms. The voltage of the battery is:

Your Answer:

3) A movie projector is equipped with a 0.5 m focal length lens that is positioned 0.405 m in front of the film. The screen must be placed for an image to be in focus is 37.5 m. What is the magnification of the image?

4) A light bulb used in a slide projector draws a current of 8 amperes when operating on 90 volts. The resistance of the light bulb in ohms is: