The 2 means there are two phosphate ions in a molecule of magnesium phosphate.
20 electrons and 2 valence electrons
is the equation that represents the Joule's law of heating.
<h3>
Explanation:</h3>
Joule's law of heating defines the heat generated by any current flowing conductor is directly proportional to
1. Square of Current (I²),
2. Resistance of the conductor (R)
3. Time for which current is passed (t)
Hence, Heat generated =
.....................(1)
By Ohm's Law, the potential difference (V) across a conductor is directly proportional to the current(I) flowing through it. The constant of proportionality is termed as resistance of the conductor (R).
...............................................(2)
From (2), Current (I) can be rewritten as
........................................................(3)
Substituting (3) in (1), we get

D. This says the path sweeps out equal segments of the elliptical path in equal times (picture a wedge of a pie shaped like an oval)
Answer:
Time of ascent is greater than time of descent.
Explanation:
The gravitational force always acts in the downward direction. The air drag always opposes the motion.
During ascent, the gravitational force and air drag act in opposite direction to the motion where as during descent, only air drag acts in opposite direction to the motion of the ball while gravitational force acts in the same direction. Thus, the time of ascent and descent become unequal with time of ascent being greater than time of descent.