What is the mass of a pure platinum disk with a volume of 113 cm3? the density of platinum is 21.4 g/cm3

what is the average speed of a person who can run around the track 4 times in 5 minutes? the track is 400 meters long.

A super train is moving along a track at a speed close to the speed of light. you are watching the train from the ground. you observe lightning to strike in two places along the track, a mile apart, at precisely the same time.

How do you think cotton, tobbaco, and other crops were shipped to their destination

A 40.0 kg wheel, essentially a thin hoop with radius 0.810 m, is rotating at 438 rev/min. It must be brought to a stop in 21.0 s. A) How much work must be done to stop it? B) What is the required average power?

Which are causes of desertification? global climate change farming deforestation overgrazing erosion

Explain fully, in your own words, why the temperature during PCR goes through cycles of 94C, 50C, 72C.

4. What is a compound? Name an example.

What is one important role that ocean waters have in heating Earth? absorb and transport solar energy transport nutrients and waste create and emit solar energy wear away rock and soil

Shelly was surprised to learn the dwarf planet Pluto used to be considered a planet. What would have had to be true for Pluto to remain categorized as a planet? Pluto would need to have an atmosphere.

Two uncharged metal spheres, #1 and #2, are mounted on insulating support rods. A third metal sphere, carrying a positive charge, is then placed near #2. Now a copper wire is momentarily connected between #1 and #2 and then removed.