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3 years ago

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Two substances, A and B, initially at different temperatures, come into contact and reach thermal equilibrium. The mass of subst

ance A is 6.01 g and its initial temperature is 20.0 degrees Celsius. The mass of substance B is 25.6 g and its initial temperature is 52.2 degrees Celsius. The final temperature of both substances at thermal equilibrium is 46.1 degrees Celsius. If the specific heat capacity of substance B is 1.17 J/g degrees Celsius, what is the specific heat capacity of substance A

1 answer:

Kaylis [27]3 years ago

5 0

Answer:

The specific heat capacity of substance A is 1.16 J/g

Explanation:

The substances A and B come to a thermal equilibrium, therefore, the heat given by the hotter substance B is absorbed by the colder substance A.

The equation becomes:

Heat release by Substance B = Heat Gained by Substance A

The heat can be calculated by the formula:

Heat = mCΔT

where,

m = mass of substance

C = specific heat capacity of substance

ΔT = difference in temperature of substance

Therefore, the equation becomes:

(mCΔT) of A = (mCΔT) of B

<u>FOR SUBSTANCE A:</u>

m = 6.01 g

ΔT = Final Temperature - Initial Temperature

ΔT = 46.1°C - 20°C = 26.1°C

C = ?

<u>FOR SUBSTANCE B:</u>

m = 25.6 g

ΔT = Initial Temperature - Final Temperature

ΔT = 52.2°C - 46.1°C = 6.1°C

C = 1.17 J/g

Therefore, eqn becomes:

(6.01 g)(C)(26.1°C) = (25.6 g)(1.17 J/g)(6.1°C)

C = (182.7072 J °C)/(156.861 g °C)

<u>C = 1.16 J/g</u>

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6. Low flammability

7. Good lubrication capability

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2 years ago

A 5-mm-thick stainless steel strip (k = 21 W/m•K, rho = 8000 kg/m3, and cp = 570 J/kg•K) is being heat treated as it moves throu

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Answer:

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Explanation:

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$B_i$ < 0.1, thus apply lumped system approximation to determine the constant time for the process;

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3 years ago

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Answer:

c. less than 60 mi/h

Explanation:

To calculate the average speed of the bus, we need to calculate the total distance traveled by the bus, as well as the total time of travel of the bus.

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S = 200 mi

Now, for total time, we calculate the times for both speeds from A to b and then B to C, separately and add them.

Total Time = t = Time from A to B + Time from B to C

t = (100 mi)/(50 mi/h) + (100 mi)(70 mi/h)

t = 2 h + 1.43 h

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Now, the average speed of bus will be given as:

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It is clear from this answer that the correct option is:

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3 years ago

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Answer:

Below see details

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A) It is attached. Please see the picture

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The power that must be supplied to the motor is 136 hp

<u>Explanation:</u>

Given-

weight of the elevator, m = 1000 lb

Force on the table, F = 500 lb

Distance, s = 27 ft

Efficiency, ε = 0.65

Power = ?

According to the equation of motion:

F = ma

$3(500) - 1000 = \frac{1000}{32.2} * a$

a = 16.1 ft/s²

We know,

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As efficiency is given and output power is known, we can calculate the input power.

ε = Pout / Pin

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Pin = 68030.8 / 500 hp

= 136 hp

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3 years ago