Advertisements
Advertisements
प्रश्न
Solve the following problems:
Equal heat is given to two objects A and B of mass 1 g. Temperature of A increases by 3°C and B by 5°C. Which object has more specific heat? And by what factor?
उत्तर
\[s = \frac{∆ Q}{m ∆ T}\]
Let Q cal of heat is given to both A and B.
For body A,
\[s_1 = \frac{Q}{1 \times 3} = \frac{Q}{3} \text {cal }g^{- 1} {}^o C^{- 1}\]
For body B,
\[s_2 = \frac{Q}{1 \times 5} = \frac{Q}{5} \text { cal } g^{- 1} {}^o C^{- 1}\]
Now,
\[\frac{s_1}{s_2} = \frac{\frac{Q}{3}}{\frac{Q}{5}} = \frac{5}{3}\]
\[ \Rightarrow s_1 = \frac{5}{3} s_2\]
Thus, specific heat capacity of body A is more than body B and by a factor of \[\frac{5}{3}\].
APPEARS IN
संबंधित प्रश्न
Given below are observations on molar specific heats at room temperature of some common gases.
| Gas |
Molar specific heat (Cv) (cal mol–1 K–1) |
| Hydrogen | 4.87 |
| Nitrogen | 4.97 |
| Oxygen | 5.02 |
| Nitric oxide | 4.99 |
| Carbon monoxide | 5.01 |
| Chlorine | 6.17 |
The measured molar specific heats of these gases are markedly different from those for monatomic gases. Typically, molar specific heat of a monatomic gas is 2.92 cal/mol K. Explain this difference. What can you infer from the somewhat larger (than the rest) value for chlorine?
Find the time taken by a 500 W heater to raise the temperature of 50 kg of material of specific heat capacity 960 J kg-1K-1, from 18°C to 38° C. Assume that all the heat energy supplied by the heater is given to the material.
How will rise in sea level affect population in coastal countries?
What is carbon tax?
(i) State whether the specific heat capacity of a substance remains the same when its state changes from solid to liquid.
(ii) Give one example to support your answer.
104g of water at 30°C is taken in a calorimeter made of copper of mass 42 g. When a certain mass of ice at 0°C is added to it, the final steady temperature of the mixture after the ice has melted, was found to be 10°C. Find the mass of ice added. [Specific heat capacity of water = 4.2 Jg–1°C–1 ; Specific latent heat of fusion of ice = 336 Jg–1; Specific heat capacity of copper = 0.4 Jg–1°C–1] .
The substances like water which have ........... Heat capacity warm up more slowly than substances like iron which have .......... heat capacity.
m kg of a substance of specific heat capacity s J/kg °C is heated so that its temperature rises from θ1°C to θ2°C. Write down the expression for the heat Q supplied.
Give two reasons as to why copper is preferred over other metals for making calorimeters.
Some heat is provided to a body to raise its temperature by 25°C. What will be the corresponding rise in temperature of the body as shown on the Kelvin scale?
A substance is in the form of a solid at 0°C. The amount of heat added to this substance and the temperature of the substance are plotted on the following graph:
If the specific heat capacity of the solid substance is 500 J/kg °G, find from the graph, the mass of the substance.
A piece of iron of mass 2.0 kg has a thermal capacity of 966 J/°C. What is its specific heat capacity in S.I. units?
Write the name.
The amount of heat absorbed at constant temperature by unit mass of a liquid to convert into gaseous phase.
Read this activity and answer the following questions.
- Take three spheres of iron, copper and lead. the lead of equal mass.
- Put all the three spheres in boiling water in the beaker for some time.
- Take the three spheres out of the water.
- All the spheres will be at a temperature 100 °C.
- Put them immediately on the thick slab of wax.
- Note, the depth that each of the sphere goes into the wax.
Questions:
- Which property is determined from this activity?
- Give name to that property.
- Explain the term principal of heat exchange with the help of this activity.
Numerical Problem.
What could be the final temperature of a mixture of 100 g of water at 90 °C and 600g of water at 20°C.
At same temperature and pressure of an ideal gas, ____________.
Two cylinders of equal height and radius are made of copper and aluminum. Which of them conducts heat faster?
Match the columns:
| Column ‘A’ | Column ‘B’ |
| The SI unit of specific heat capacity | (a) Jkg−1°C−1 |
| (b) kg/m3 | |
| (c) calorie |
Give one example where high specific heat capacity of water is used as heat reservoir.
