Einstein's equation E = mc2 describes the conversion of mass to energy that occurs during nuclear fusion. If a billion joules of energy are released by this process, how much mass has been consumed? (Recall, a joule is a Nt-m or kg-m2/s2 and the speed of light is ~300 million m/s.)

Astronomers observe huge bubbles of hot gas, some over a thousand light years across, in the Milky Way. What is their cause?

What will be an ideal response?

One year

a) has more sidereal days than solar days. b) has more solar days than sidereal days. c) always has exactly 365 sidereal days. d) is based entirely on Earth's rotation rate.

Consider two transformers. Transformer A has 300 turns on its primary and 500 turns on its secondary. Transformer B has 250 turns on its primary and 1000 turns on its secondary

The same voltage is supplied at the primary of both transformers. The secondary voltage in transformer A has an amplitude V = 50 V. What is the amplitude of the secondary voltage on transformer B? A) 120 V B) 2400 V C) 1200 V D) 60 V E) 240 V

Where groundwater discharges to a stream, the elevation of the water table next to the stream

A) is lower than the surface of the stream. B) is the same as the surface of the stream. C) is higher than the surface of the stream. D) Not enough information given