If the cross-section of a wire of fixed length is doubled, how does the resistance of that wire change? (this is for studying for my semester exam. i got the question wrong on one of my chapter tests so i'm trying to find out what the correct answer was) a. halved b. doubled (i know it's not this cause that was the wrong one) c. unchanged d. quadrupled

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

This question is worth 54 points ! rock falls from a ledge to the ground what energy conversion occurs during this process a potential to kinetic b kinetic to potential c thermal to mechanical d chemical to mechanical

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?