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3 years ago

12

Please help me,its urgent!!

1 answer:

GREYUIT [131]3 years ago

4 0

Test:

Performing a Litmus Test

Result:

Litmus paper gives the user a general indication of acidity or alkalinity as it correlates to the shade of red or blue that the paper turns.

To test the pH of a substance, dip a strip of litmus paper into the solution or use a dropper or pipette to drip a small amount of solution onto the litmus paper.
Blue litmus paper can indicate an acid with a pH between 4 and 5 or lower.
Red litmus paper can show a base with a pH greater than 8.
If a solution has a pH between 5 and 8, it will show little color change on the litmus paper.
A base tested with blue litmus paper will not show any color change, nor will an acid tested with red litmus paper register a change in color.

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Why would a person who weighs 100 lbs. on Earth weigh significantly more on Ju-piter?

Nitella [24]

Answer:

Is a

Explanation:

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3 years ago

Problem #3: 3.6. A diode has wdo = 0.4 µm and φj = 0.85 V. (a) What reverse bias is required to triple the depletion-layer width

Alchen [17]

Answer:

a) 6.8 Volt

b) 1.21Цm

Explanation:

We are given from the question that

The zero -bias depletion layer width( $W_{do}$ ) is 0.4Цm

The built in voltage φj is 0.85V

Now to calculate the reverse voltage( $V_{R}$ ) that would be required to triple the depletion - layer width.

The depletion - layer width ( $W_{d}$ ) of the diode has the formula

$W_{d} = W_{do} \sqrt{1 + \frac{V_{R} }{Qj} }$

For three times of $W_{d}$ we have

$3W_{d} = W_{do} \sqrt{1 +\frac{V_{R} }{Qj} }$

=> $\frac{V_{R} }{Qj} = 3^{2} -1$

=> $V_{R} = 8Qj$

Substituting value of φj

We have

$V_{R} = 8(0.85V)$

= 6.8 V

The required bias voltage $V_{R}$ is 6.8 V

The solution for the b part of the question is uploaded on first image

7 0

3 years ago

The small metal cylinder has a mass of 0.20 kgkg, the coefficient of static friction between the cylinder and the turntable is 0

deff fn [24]

Answer:

velocity of the metal cylinder = 0.343 m/s

Explanation:

Force putting the metal cylinder is given by

F = mv²/r

But this force will balance the frictional force between the metal cylinder and the turntable

The frictional force is given by

μN = μ × mg = 0.08 × 0.2 × 9.81 = 0.15696 N

r = 0.15 m, m = 0.2 kg,

F = mv²/r = 0.2 v²/(0.15) = 1.3333 v²

1.3333 v² = 0.15696

v² = 0.117

v = 0.343 m/s

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3 years ago

An electric pump rated 1.5 KW lifts 200kg of water through a vertical height of 6m in 10 secs: way is the efficiency of the pump

ruslelena [56]

Answer:

80%

Explanation:

Efficiency = Power output / Power input × 100 %

To calculate efficiency we need to find power output of electric pump.

We can use,

Work done = Energy change

Work done per second = Energy change per second

Work done per second = Power

Therefore, Power = Energy change per second

= Change in potential energy of water per second

=mgh / t

= 200× 10×6 / 10

= 1200 W = 1.2 kW

Now use the first equation to find efficiency,

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3 years ago

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MatroZZZ [7]

Answer:

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Explanation:

It would be this because sound travels faster through a solid rather than a liquid.

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3 years ago