A+5+watt+led+bulb+converts+80%+of+t he+power+into+light+photos+of+wavel ength+660+nm. +what+is+the+number+of+photons+emit ted+from+the+bulb+in+one+second??.

Iron reacts with sulfur to form iron sulfide. if 60 grams of iron reacts with sulfur to produce 90 grams of iron sulfide, how much sulfur has been used in the chemical reaction?

Acup of coffee sits on the dashboard of an automobile. the car goes around a sharp curve. even though you hold the cup still, coffee still splashes out. this can best be explained due to a) density. b) friction. c) gravity. d) inertia.

The earth is constantly spinning on its axis, like you might spin a basketball on your finger. it is this spinning of the earth that causes