Question

Problem 4: Consider the following circuit. If a wire were added to the circuit as shown in the diagram below,

Part (a) Would the current through bulb A increase, decrease or remain the same? Explain your reasoning. EssayAdvanced   : = __________________________________________ Part (b) Would the current through bulb D increase, decrease or remain the same? Explain your reasoning. EssayAdvanced   : = __________________________________________ Part (c) Would the current through bulb C increase, decrease or remain the same? Explain your reasoning. EssayAdvanced   : = __________________________________________ Part (d) Would the current through the battery increase, decrease or remain the same? Explain your reasoning. EssayAdvanced   : = __________________________________________ Part (e) Would the potential difference across bulb A increase, decrease or remain the same? Explain your reasoning. EssayAdvanced   : = __________________________________________ Part (f) Would the potential difference across bulb D increase, decrease or remain the same? Explain your reasoning. EssayAdvanced   : = __________________________________________ Part (g) Would the potential difference across bulb C increase, decrease or remain the same? Explain your reasoning. EssayAdvanced   : = __________________________________________ Part (h) Would the potential difference across the battery increase, decrease or remain the same? Explain your reasoning. EssayAdvanced   : = __________________________________________

Answer 1

let each bulb has resistance R,then when a wire is added in the circuit TD

there is short circuit in this case, so no current flow through bulb A and B eq 2 Equivalent resistance of the circuit decreases so current through battery increases Part (a) current through bulb A decreases, because bulb A is in short circuit condition so no potential difference hence no current but earlier there was flow of current through A, so current decreases Part (b) current through bulb D remains same, there is no change in potential difference across bulb D when wire is added hence current remains same Part (c) Before After current through bulb c increases, because potential difference across bulb c increases when wire is added hence current increases

Part (D) Before R 0.6 After R 0.5R So current through the battery increases Part (e) Before After Potential difference across bulb A decreases

Part (f) Before After Potential difference across bulb D remains the same Part(g) Before After Potential difference across bulb c increases Part(h) battery is ideal having no internal resistance so Potential difference across battery remains the same as before