Answer:
4m/s2
Explanation:
acceleration=v-u/t...v=12m/s,u=0m/s,t=3sec
a=12-0/3
=4m/s2
Is there information in the previous question which relates to this one?
Let's call R the value of the resistance of the two resistors. In the first situation, the resistors are connected in parallel, so their equivalent resistance is given by:

which means:

And calling I the current in the circuit, the voltage is given by Ohm's law:

In the second situation, the resistance of each resistor is doubled: R'=2R. So, the equivalent resistance in this case is given by

which means

And the new voltage is given by:

<span>which is twice the original voltage, so the voltage has doubled.
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