<span>The
formation of the Solar System began 4.6 billion years ago with the
gravitational collapse of a small part of a giant molecular cloud. Most
of the collapsing mass collected in the center, forming the Sun, while
the rest flattened into a proto-planetary disk out of which the planets,
moons, asteroids, and other small Solar System bodies formed.
Hope it helped
</span>
1. All the relevant resistors are in series, so the total (or equivalent) resistance is the sum of the resistances of the resistors: 20 Ω + 80 Ω + 50 Ω = 150 Ω [choice A].
2. The ammeter will read the current flowing through this circuit. We can find the ammeter reading using Ohm's law in terms of the electromotive force provided by the battery: I = ℰ/R = (30 V)(150 Ω) = 0.20 A [choice C].
3. The voltmeter will measure the potential drop across the 50 Ω resistor, i.e., the voltage at that resistor. We know from question 2 that the current flowing through the resistor is 0.20 A. So, from Ohm's law, V = IR = (0.20 A)(50 Ω) = 10. V, which will be the voltmeter reading [choice F].
4. Trick question? If the circuit becomes open, then no current will flow. Moreover, even if the voltmeter were kept as element of the circuit, voltmeters generally have a very high resistance (an ideal voltmeter has infinite resistance), so the current moving through the circuit will be negligible if not nil. In any case, the ammeter reading would be 0 A [choice B].
Answer: 
Explanation:
Given
Charge discharged 
time taken 
Current is given as rate of change of discharge i.e.
Therefore, the average current is
The formula of the kinetic energy is:
where m is a mass of the object, v is speed of the object at the moment of time. So we have:
The answer is
2000 Joules.
