18.1
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Revision as of 16:40, 31 January 2010 by 10schrimpa (talk | contribs) (New page: ===1. How much current flows if you connect a 2.34 ohm resistor to a 12.0V battery?=== <br> Use I = V/R <br> I = 12/2.34 <br> I = 5.128A <br><br> ===2. If 0.129 amps of current flow thro...)
Contents
- 1 1. How much current flows if you connect a 2.34 ohm resistor to a 12.0V battery?
- 2 2. If 0.129 amps of current flow through a 45 ohm resistor, what is the power dissipated?
- 3 3. If a current of 345mA flows, how much charge will pass by in one minute?
- 4 4. A 85 ohm heating element is connected to 120V. In what time can the heating element raise the temperature of 2.4kg of water initially at 12C to 85C?
- 5 5. A 1200W heater runs on alternating current with a peak voltage of 134V. What is its resistance?
1. How much current flows if you connect a 2.34 ohm resistor to a 12.0V battery?
Use I = V/R
I = 12/2.34
I = 5.128A
2. If 0.129 amps of current flow through a 45 ohm resistor, what is the power dissipated?
Use P = (I^2)(R)
P = (.129^2)(45)
P = .7488W
3. If a current of 345mA flows, how much charge will pass by in one minute?
Use I = Q/T
Q = (.345)(60)
Q = 20.7C
4. A 85 ohm heating element is connected to 120V. In what time can the heating element raise the temperature of 2.4kg of water initially at 12C to 85C?
Use (V^2)/R = ((m)(c)(delta Temp))/time
120^2/85 = (2.4*4186*(85-12))/t
t = 4329.02, about 4300sec
5. A 1200W heater runs on alternating current with a peak voltage of 134V. What is its resistance?
Vrms=134/(square root of 2)
Vrms=94.7
P=(V^2)(R)
R = (94.7^2)/1200
R = 7.48 about 7.5ohms
