phil is trying to reduce the resistance of a 12-volt device that uses 3 amps of electricity . His goal is 3 ohms of resistnace. by how many ohms does he need to reduce the resistance of the device to achieve his goal? if the resistnace is lowered to 3 ohms, how many amps of current will there be?
i need help fast
** please explain
2006-12-11 13:46:09 · 5 answers · asked by lex 1 in Science & Mathematics ➔ Engineering
18 i think dont know i am only in the 5 grade
2006-12-11 13:48:32 · answer #1 · answered by brownsuagr569 2 · 0⤊ 1⤋
One of the implications of Ohm's law states that Ohms = Volts/Amps. He currently uses 12/3 or 4 ohms. Reducing his device by one ohm will do it.
2006-12-11 13:52:31 · answer #2 · answered by claywlong 2 · 0⤊ 0⤋
You're going to need to use ohm's law here. Ohm's law is the equation V=IR where V is volts, I is the current (in amps), and R is the resistance (in ohms).
V=IR
12=3(R)
R=4 ohms
So, he needs to reduce the resistance by one ohm. (4-1=3 ohms)
V=IR
12=I(3)
I=4 amps in the new circuit
Hope that helps you and good luck!!
2006-12-11 13:52:42 · answer #3 · answered by moleman_992 2 · 0⤊ 0⤋
Voltage = Current x Resistance (V = I * R), so R = V/I and 12V / 3A = 4 ohms currently. To lower total resistance to his target of 3 ohms, he must reduce resistance 1 ohm.
Once lowered, I = V/R = 12V / 3 ohms = 4 amps.
2006-12-11 14:28:58 · answer #4 · answered by roynburton 5 · 0⤊ 0⤋
The initial R:
V=IR so 12=3xR R=4
so he needs to reduce it by 1 ohm.
Now 12=Ix3 so I=4 amps
2006-12-11 13:50:35 · answer #5 · answered by scubamasterme 3 · 0⤊ 0⤋