Amachine that promises more energy output than input is? ?

After a car's engine has been running for a while, if you stand near the car's engine you can often feel heat coming from the engine as a result of a. radiation b. convection c. conduction

1. how to locate the image in converging(concave) mirror and diverging (convex) mirror with salt. 2. how to locate the image in a converging (convex) lens and diverging (concave) lens with salt.

Match these items. 1. coulombs __force 2. ohms __emf 3. centimeters __resistance 4. newtons __charge 5. volts __length