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dimulka [17.4K]
3 years ago
7

When a resistor is connected to a 12 volt source, it draws a 185 mA current. what's the resistance? (I said 65 ohms). the same r

esistor connected to a 90 volt source draws a 1.25 amp current. what's the resistance? is it ohmic?
Physics
1 answer:
lyudmila [28]3 years ago
8 0

Resistance-1 = (voltage-1) / (current-1) =

                       (12 V)  /  (0.185 A)  =  64.9 ohms .

Resistance-2 = (voltage-2) / (current-2) =
 
                           (90 V )  /  (1.25 A)  =  72 ohms .

The resistance changed between situation-1 and situation-2 .
How did that happen ?

Power = (voltage) x (current)

Power-1 = (12)  x  (0.185)  =  2.22 watts

Power-2 = (90)  x  (1.25)  =  112.5 watts

The poor resistor dissipated 51 times as much power during
the second trial.  It got all heated up, and its resistance went
through the roof.

Carbon resistors behave nicely and reliably, until you try to
toast bread or light up your bedroom with them.


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V_{avg} = \frac{Final \ position\  - \ Initial \ position}{final \ time\  - \ initial \ time}\\\\V_{avg} = \frac{240km \ - \ 60km}{2hr\  - \ 1hr} \\\\V_{avg} = \frac{180 \ km}{1hr} \\\\V_{avg}= 180 \ km/hr

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The answers are located in each of the explanations showed below

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[\frac{m}{s} ]^{2} =[\frac{m}{s} ]^{2} + 2* [\frac{m}{s^{2} } ]*[m]\\

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[\frac{m^2}{s^2} ]

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2

a) Pascal's principle or Pascal's law, where the pressure exerted on an incompressible fluid and in balance within a container of indeformable walls is transmitted with equal intensity in all directions and at all points of the fluid.

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P1 = F1/A1

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The mosquitoes that can sit on the water.

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Some leaves that remain floating on the surface.

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