When is the zebra moving and when is it not moving

We are measuring the spectra of two hydrogen gas clouds. The laboratory frame wavelength of one hydrogen line is 656.2 nm. Cloud A's emission line wavelength is 660.1 nm and Cloud B's emission line wavelength is 670.1 nm.

Where would you expect to find the center of gravity in a plastic ruler

Lauren's friend asked her to come hang out this weekend with some people from the school tennis team. what question should lauren ask to protect her heath and safety? a) what will we be doing? b) what will you be wearing?

How much time does it take for the water to go from the top to bottom 4.5 m/s 53m?

Which statement describes an atomic nucleus? An atomic nucleus is negatively charged. An atomic nucleus has no electrical charge. An atomic nucleus consists of mostly empty space. An atomic nucleus contains most of the atom's mass.

The football player running toward the goal line has A. Potential energy B. Chemical energy C. Kinetic energy D. Elastic potential energy

If the density of an object is 30 g/cm3 and its volume is 10 cm3, what is its mass in grams?

Explain how atoms are aligned in a magnet in terms of the North and South poles.

Which of the following has the largest gravitational potential energy A. a 10kg dog running down the street at 30mph B. a tightrope walker slowly crossing niagara falls C. a 0.02kg bullet moving down the barrel at 800mph D.

Why does the speed of an object change when a force acts on it?