Stretching of the Universe. An observed distant white dwarf supernova had a redshift of z = 1.7. How does the average distance between galaxies now compare with the average distance between galaxies at the time the supernova exploded?

You notice a very one-dimensional-thinking snail crawling along one rail of a railroad track. naturally, you remove it to a safer place. but before you do, you observe it as it moves from position xi = -92.9 cm to position xf = -64.9 cm along the rail, as measured from a point where one rail abuts the next. what is the snail\'s displacement δx in centimeters?

A110-pound person pulls herself up 4.0 feet. this took her 2.5 seconds. how much power was developed? 0.13 hp 0.32 hp 2.0 hp 3.1 hp

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