Four identical metal plates are painted either black or white and have either a dull or shiny surface. They are heated to the same temperature.

Which plate radiates thermal energy at the greatest?
A. the plate that is dull and black
B. the plate that is dull and white
C. the plate that is shiny and black
D. the plate that is shiny and white

How many dots must be added to the symbol to properly represent a standard nitrogen ion? a) 1 b) 3 c) 5 d) 8

Which of the following is an example of motion in two dimensions?

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?