When do comets have tails?
A) when they are relatively close to the Sun
B) when they are close to a massive planet like Jupiter
C) only after a collision with a smaller object
D) when they are young
E) Comets always have tails.
A) when they are relatively close to the Sun
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What is the maximum value of the electric field E at 1.5 m from a 102-W light bulb radiating in all directions? (µ0 = 4? × 10^?7 T?m/A, c = 3.00 × 10^8 m/s)
a. 5.2E+1 V/m b. 4.1E+3 V/m c. 2.7E+3 V/m d. 8.5E+2 V/m e. 3.2E+2 V/m
A(n) _______________ can thrive in extreme conditions, such as ice-covered lakes in Antarctica, far underground inside solid rock, amongst the cinders of summits of extinct volcanoes, or in pools of acids
Fill in the blank(s) with correct word
Which was a contribution to astronomy made by Copernicus?
A) The planets move around the Sun in elliptical orbits. B) His theory of gravity accounted for the variable speeds of the planets. C) He laid out the order and relative motion of the known solar system. D) He discovered the Sun was not at the center of the Milky Way. E) His telescope revealed the four moons of Jupiter, a model solar system.
The sidereal month is ________.
A. the time the Moon takes to complete an orbit relative to the background stars B. the time between successive new moons C. the time it takes the Moon to complete an orbit relative to the Sun D. the time it takes Earth to rotate 30 times on its axis E. None of these choices is correct.