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| 1. |
How many 176 ohms resistor in parallel are required, to carry 5 ampere on a 220 volt line? |
| Answer» In n resistors each of resistance R are connected in parallel, then net resistance\xa0Rp is:\xa0{tex}\\frac1{R_p}=\\;\\frac1R+\\frac1R+.........\\;n{/tex} times\xa0{tex}\\;\\frac{1\\;+\\;1\\;+..............n\\;times}R=\\frac nR{/tex}{tex}\\;R_p=\\frac Rn{/tex}\xa0Now {tex}\\;R_p=\\frac VI=\\;\\frac{220}5\\;=\\;44\\;\\Omega{/tex}{tex}\\frac Rn{/tex}= 44 but R = 176 Ω{tex}\\;\\frac{176}n\\;{/tex}= 44 or n = 44 resistors each 176 Ω connected in parallel with result in net resistance of 44 Ω causing a current of 5A to flow through when connected to 220V. | |