A region of space that contains no matter

Who was the first person to discover wormholes?

A plant has a weight of 24.5n. what is the mass of the plant

What are the two possible outcomes for a Blue Supergiant

You move a 4 N object 10 meters. Find work

Why is too much exposure to ultraviolet radiation dangerous

A tube, open at only one end, is cut into two shorter (nonequal) lengths. The piece that is open at both ends has a fundamental frequency of 422 Hz, while the piece open only at one end has a fundamental frequency of 666 Hz.

Table tennis the path of a table-tennis ball after being hit and hitting the surface of the table can be modeled by the function h=-4.9t (t-0.42) where h is the height in meters above the table and t is the time in seconds.

A coat rack weighs 65.0 lbs when it is filled with winter coats and 40.0 lbs when it is empty. The base of the coat rack has an area of 452.4 in2.

An initially stationary object experiences an acceleration of 6 m/s2 for a time of 15 s. How far will it travel during that time?

How was helium first discovered? mining of the radioactive element uranium using spectral analysis of the Suns' emission spectra o hubble obtaining samples from explosions off the surface of the sun deep sea mining off the coast of Texas