Voltage, V = Current, I x Resistance, R (V is directly proportional to I where R is constant of proportionality)
This means that when Voltage is increased, Current increases and when voltage is decreased, current decreases (and the inverse is true). Through all this though, resistance remains constant regardless.
This question can be answered by using conversation of energy.
Explanation:
Note that we take because we are looking for the minimum initial speed for the penguin to reach the top of the second hill. Any other speed more than this will already be enough for him.
