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Black_prince [1.1K]
2 years ago
8

1- The preexponential and activation energy for the diffusion of iron in cobalt are 1.1×10-5 m 2 /s and 253,300 J/mol, respectiv

ely. At what temperature will the diffusion coefficient have a value of 2.1×10-5 m 2 /s ?
Engineering
1 answer:
n200080 [17]2 years ago
4 0

The temperature at which the diffusion coefficient have a value of 2.1×10-5 m 2 /s is  -47078 K.

Using the relation;

logD = logDo - Ea/2.303RT

D = diffusion coefficient

Do =  preexponential

Ea = activation energy

R = gas constant

T = temperature

Substituting values;

log(2.1×10-5)= log (1.1×10-5 ) - 253,300/2.303 × 8.314 × T

log(2.1×10-5) -  log (1.1×10-5 ) =  - 253,300/2.303 × 8.314 × T

log[2.1×10-5/1.1×10-5] = - 253,300/2.303 × 8.314 × T

0.281 × (2.303 × 8.314 × T) = - 253,300

T =  - 253,300/2.303 × 0.281 × 8.314

T = -47078 K

Learn more: brainly.com/question/14283892

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If the rotational speed of a pump motor is reduced by 35%, what is the effect on the pump performance in terms of capacity, head
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Answer:

- the capacity of the pump reduces by 35%.

- the head gets reduced by 57%.

the power consumption by the pump is reduced by 72%

Explanation:

the pump capacity is related to the speed as speed is reduces by 35%

so new speed is (100 - 35) = 65% of orginal speed

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which means that the capacity of the pump is also reduces by 35%.

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