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Georgia [21]
3 years ago
11

a cell supplies a current 0.9A through a resistance of 2 ohms and a current of 0.3A through a resistance of 7 ohms. what is inte

rnal resistance
Physics
1 answer:
umka2103 [35]3 years ago
8 0

We model the cell's internal resistance as an additional resistor in the circuit. We will use V = IR to calculate the voltage drops over each resistor for both circuits.

Circuit 1: 0.9A current, internal resistance r, resistor 2Ω

V = 0.9r + 0.9(2) = 0.9r + 1.8

Circuit 2: 0.3A current, internal resistance r, resistor 7Ω

V = 0.3r + 0.3(7) = 0.3r + 2.1

Since V should be the same for both circuits, set the total voltage drops equal to each other and solve for r:

0.9r +1.8 = 0.3r + 2.1

0.6r = 0.3

r = 0.5Ω

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Answer:

f=-1380N

Explanation:

A karate master wants to break a board by hitting the board swiftly with his hand. The master's hand has a mass of 0.30 kg, and as it strikes the board, his hand has a velocity of 23.3 m/s. The master contacts the board for 0.0050 seconds

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solution

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f=m(v-u)/t

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f=force impact

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when you're in your house and hear a car drive by outside, how many different mediums do sound waves from the car engine have to
snow_lady [41]

Answer:

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Explanation:

8 0
3 years ago
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Answer:

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λ is the wavelength of the wave measured using m.

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Explanation:

6 0
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Part A
jasenka [17]

Answer:

answer on the google

Explanation:

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