$$200$$ g of water at $$20^\circ$$C and $$300$$ g of water at $$70^\circ$$C are mixed in a calorimeter of negligible heat capacity. Assume no loss of heat. The final temperature is:
1. $$40^\circ$$C
2. $$50^\circ$$C
3. $$60^\circ$$C
4. $$45^\circ$$C
Subtopic: Â Calorimetry |
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Two liquids flow through a heat exchanger and exchange heat energy.
The first liquid has a mass flow rate $$\Big(\frac{dm}{dt}\Big)=r_1,$$ and its temperature rises by $$\Delta\theta_1.$$ For the second liquid, the flow rate $$\Big(\frac{dm}{dt}\Big)=r_2,$$ and the temperature fall is $$\Delta\theta_2.$$ The ratio of their specific heat capacities is:
1.  $$\frac{\Delta\theta_1}{\Delta\theta_2}$$
2.  $$\frac{r_1}{r_2}$$
3.  $$\frac{r_2\Delta\theta_2}{r_1\Delta\theta_1}$$
4.  $$\frac{r_2\Delta\theta_1}{r_1\Delta\theta_2}$$
Subtopic: Â Calorimetry |
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The specific heat capacity of a body depends on:

 1 the heat given 2 the temperature raised 3 the mass of the body 4 the material of the body
Subtopic: Â Calorimetry |
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When $$0.15$$ kg of ice at $$0^\circ \text{C}$$ is mixed with $$0.30$$ kg of water at $$50^\circ \text{C}$$ in a container, the resulting temperature is $$6.7^\circ \text{C}.$$
The heat of fusion of ice is: ($$S_{\text{water}}=4186$$ J kg-1 K-1)
1. $$3.43 \times 10^4$$ Jkg-1
2. $$3.34 \times 10^4$$ Jkg-1
3. $$3.34 \times 10^5$$ Jkg-1
4. $$4.34 \times 10^5$$ Jkg-1

Subtopic: Â Calorimetry |
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