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3 years ago

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Two AAA-size lithium batteries are connected in series in a flashlight. Each battery has 3.5 volt and 4- Amp-hour capacity. If t

he flashlight is connected to a light bulb with 10 Ohms resistance. How long does it take to drain the batteries?

1 answer:

mafiozo [28]3 years ago

7 0

Answer:

t= 9.79 hr

Explanation:

Given that

V= 3.5 V

Capacity= 4 Amp-hour

We know that

V= IR

V= Voltage

I =Current

R=Resistance

V = I R

The total voltage on the batteries will be 2 V

2 x 3.5 = I x 10

I= 0.7 A

We know that Power P

P = V I

P = 0.7 x 7

P =4.9 W

4 A.h and 12 volt power supply = 4 x 12 = 48 W.hr

So time of drain t

4.9 t = 48

t= 9.79 hr

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b) attached in image

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b) diagram is attached

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|H(F)| in dB = 20log |H(F)|

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Explanation:

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The minimum power supplied to the heat pump is:

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Air at 40C flows over a 2 m long flat plate with a free stream velocity of 7 m/s. Assume the width of the plate (into the paper)

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Complete Question

Air at 40C flows over a 2 m long flat plate with a free stream velocity of 7m/s. Assume the width of the plate (into the paper) is 0.5 m. If the plate is at a co temperature of 100C,find:

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Answer:

$q=1.7845$

Explanation:

From the question we are told that:

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Width $w=0.5$

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