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4 years ago

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A piece of glass has a temperature of 72.0 degrees Celsius. The specific heat capacity of the glass is 840 J/kg/deg C. A liquid

that has a temperature of 40.0 degrees Celsius is poured over the glass, completely covering it, and the temperature at equilibrium is 57.0 degrees Celsius. The mass of the glass and the liquid is the same. Determine the specific heat capacity of the liquid

1 answer:

Nezavi [6.7K]4 years ago

5 0

Answer:

741 J/kg°C

Explanation:

Given that

Initial temperature of glass, T(g) = 72° C

Specific heat capacity of glass, c(g) = 840 J/kg°C

Temperature of liquid, T(l)= 40° C

Final temperature, T(2) = 57° C

Specific heat capacity of the liquid, c(l) = ?

Using the relation

Heat gained by the liquid = Heat lost by the glass

m(l).C(l).ΔT(l) = m(g).C(g).ΔT(g)

Since their mass are the same, then

C(l)ΔT(l) = C(g)ΔT(g)

C(l) = C(g)ΔT(g) / ΔT(l)

C(l) = 840 * (72 - 57) / (57 - 40)

C(l) = 12600 / 17

C(l) = 741 J/kg°C

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Answer:

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The buoyant force on an object in water is equal to the weight of water that this object displaces. When this disk is submerged under water, it will displace approximately $\rm 0.0114009\; m^{3}$ of water. The buoyant force on the disk will be:

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The size of this disk's weight is greater than the size of the buoyant force on it when submerged under water. As a result, the disk will sink when placed in water.

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