Question
FOR CIRCUITS PART 2 POTENTIAL DIFFERENCE Previously, we developed a model to account for the behavior of simple circuits in which bulb brightness can be used as an indicator of amount of current through that bulb. In this tutorial, we extend this model to include the concept of potential difference. Current and resistance I. Review: The circuits at right contain identical batteries bulbs. The boxes labeled X and Y represent differen unknown elements. (Assume there are no batteries in is observed that the bulb on the left is brighter than the bulb on the right. A. current through the bulb grearerthan, less than or equal o the current through the unknown element? B. In each circuit, is the current through the bulb greater than, less than, or equal to the current through the battery? Based on the observation of the relative brightnesses of the bulbs, is the resistance of element X greater than, lear than or equal to that of element Y? Explain. IL Batteries in series Auk a tutorial instnuctor for the
Explanation / Answer
i) The bulb on the left is brighter implies that it gas got more wattage than that in right
P = I V = I^2 R
A)The current in left circuit is greater than that in right. Since the value of P = VI is greater for X and V is same in both
B)The current in the left circuit is greater.
C)The resistance of bulb Y is greater than that of X. Since P = I^2 R = V^2/R, so more the resistance less the power and brightness.
