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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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Answer:

To calculate the predicted surface elevation of a 50km thick crust above a surface of 2.5km we are given a density of 3 gram per centimeter cube.

The displacement of the material will be calculated by subtracting the surface elevation of 2.5 km from the 50 km thick crust. Therefore 50-25= 47.5 km.

Thus let the density of the material be Pm

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Therefore: Pm= (50*3)/47.5= 3.16gram per centimeter cube

Thus with an average density of 2.8gram per centimeter cube

50*2.8= (50-x)*3.16

(50-x)= (50*2.8)/3.16

50-x=44.3

x=50-44.3= 5.7

Explanation:

To calculate the predicted surface elevation of a 50km thick crust above a surface of 2.5km we are given a density of 3 gram per centimeter cube.

The displacement of the material will be calculated by subtracting the surface elevation of 2.5 km from the 50 km thick crust. Therefore 50-25= 47.5 km.

Thus let the density of the material be Pm

50*3= 47.5*Pm

Therefore: Pm= (50*3)/47.5= 3.16gram per centimeter cube

Thus with an average density of 2.8gram per centimeter cube

50*2.8= (50-x)*3.16

(50-x)= (50*2.8)/3.16

50-x=44.3

x=50-44.3= 5.7

5 0
3 years ago
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Answer:

A or B you choose

Explanation:

This is called current electricity or an electric current. A lightning bolt is one example of an electric current, although it does not last very long. Electric currents are also involved in powering all the electrical appliances that you use, from washing machines to flashlights and from telephones to MP3 players.

what is an electrical current, amp, ampere Current is the flow of electrons. When a circuit is closed then a current of electrons can flow and when a circuit is open then no current can flow. We can measure the flow of electrons just like you can measure the flow of water through a pipe.

4 0
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The answer is below!!

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