This physics problem tests your understanding of fundamental physical laws and their applications. The step-by-step solution below breaks down the problem using relevant equations and physical reasoning.
ScanSolve AI Answer
Here are the solutions to the problems. 7. Step 1: Identify the given values and the formula for resistance. Given resistivity () = 1.9 × 10^-8 \, · m. Given length (L) = 20 \, m. Given resistance (R) = 0.4 \, . The formula relating resistance, resistivity, length, and cross-sectional area (A) is: R = (L)/(A) Step 2: Rearrange the formula to solve for the cross-sectional area (A). A = (L)/(R) Step 3: Substitute the given values into the rearranged formula and calculate A. A = (1.9 × 10^-8 \, · m) × 20 \, m0.4 \, A = 1.9 × 10^-8 × 200.4 \, m^2 A = 38 × 10^-80.4 \, m^2 A = 95 × 10^-8 \, m^2 A = 9.5 × 10^-7 \, m^2 The cross-sectional area of the conductor is 9.5 × 10^-7 \, m^2. Problem 2 (Circuit with three resistors): Step 1: Calculate the total resistance for resistors in series. Given resistors: R_1 = 2 \, , R_2 = 4 \, , R_3 = 6 \, . For resistors in series, the total resistance (R_total) is the sum of individual resistances: R_total = R_1 + R_2 + R_3 R_total = 2 \, + 4 \, + 6 \, R_total = 12 \, Step 2: Use Ohm's Law to find the total current. Given total voltage (V) = 12 \, V. According to Ohm's Law, V = I R_total, where I is the total current. I = (V)/(R_total) I = 12 \, V12 \, I = 1 \, A The current flowing through the circuit is 1 A. Problem 3 (Circuit with two resistors in parallel): Step 1: Calculate the equivalent resistance for resistors in parallel. Given resistors: R_1 = 3 \, , R_2 = 6 \, . For resistors in parallel, the reciprocal of the equivalent resistance (R_eq) is the sum of the reciprocals of individual resistances: (1)/(R_eq) = (1)/(R_1) + (1)/(R_2) (1)/(R_eq) = (1)/(3 \, ) + (1)/(6 \, ) (1)/(R_eq) = (2)/(6 \, ) + (1)/(6 \, ) (1)/(R_eq) = (3)/(6 \, ) (1)/(R_eq) = (1)/(2 \, ) R_eq = 2 \, Step 2: Use Ohm's Law to find the total voltage applied to the circuit. Given total current (I_total) = 4 \, A. According to Ohm's Law, V = I_total R_eq, where V is the total voltage. V = (4 \, A) × (2 \, ) V = 8 \, V The voltage applied to the circuit is 8 V. That's 2 down. 3 left today — send the next one.