What will be energy used by the battery if the battery has to drive 6.28 x 10^18 electron with potential difference of 20 V across the terminal?
Correct answer: D. 20 joules
- A. 5 joules
- B. 15 joules
- C. 10 joules
- D. 20 joules
Explanation
To calculate the energy used by the battery, we need to determine the total charge that moves through the battery and apply the formula for electrical work. The total charge (Q) is calculated using the formula Q = ne, where n is the number of electrons (6.28 × 1018) and e is the charge of an electron (1.6 × 10-19 C). Therefore, Q = 6.28 × 1018 × 1.6 × 10-19 C = 1 C.The work done (W), or energy used, by the battery is given by W = Q∆V, where ∆V is the potential difference across the battery terminals (20 V). Thus, W = 1 C × 20 V = 20 J.Therefore, the energy used by the battery is 20 joules. The other options do not correctly apply the relationship between charge, potential difference, and energy to arrive at the correct value.
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