Does a light bulb with a greater wattage have a greater brightness

The focal length of a relaxed human eye is approximately 1.7 cm. when we focus our eyes on a close up object, we can change the refractive power of the eye by about 16 diopters. (a) does the refractive power of our eyes increase or decrease by 16 diopters when we focus closely? explain. (b) calculate the focal length of the eye when we focus closely.

Give an example in which the electrical energy changes to light energy

If you put a helium-filled balloon in the refrigerator, what will happen?