SCERT Maharashtra solutions for साइंस एण्ड टेक्नॉलोजी पार्ट १ [अंग्रेजी] कक्षा १० महाराष्ट्र राज्य बोर्ड chapter 5 - Heat [Latest edition]

If pressure increases, the melting point of a substance ______.

The vapour content in the air is measured by ______.

Humid and dry nature of air depends on the ______.

Vapours in air condenses to form ______.

When the temperature of water decreases below 4 °C it’s volume _______.

In a region with a cold climate the aquatic animals can survive at 4 °C, because _______.

From the options given below the specific heat of _______ is maximum.

Ice-ball is prepared from shredded ice again. This is the example of _______.

The SI unit of specific heat is _______.

_______ apparatus is used to study the anomalous behaviour of water.

_______ heat is necessary to raise 1 kg of water from 14.5 °C to 15.5 °C.

When ice is converted into water : constant temperature : : before the water evaporates : _______

Relative humidity greater than 60% : humid air : : relative humidity less than 60% : _______

While studying anomalous behaviour of water in Hope’s apparatus, the upper temperature of the thermometer : 0 °C : : lower temperature of the thermometer : _______

The density of water is high at 4 °C : anomalous behaviour of water : : shredded ice converted into solid ice balls : _______

Specific latent heat of vaporisation : J/kg : : specific heat : _______

Find the odd one out and give its explanation.

Find the odd one out and give its explanation.

Find the odd one out and give its explanation.

Define boiling point of a liquid.

What is meant by regelation?

How fog is formed?

What is a dew point temperature?

What does the existence of drops of water on the leaves of a tree in the morning indicate?

Which temperature segment is chosen when determining the unit of heat? Why?

Match the columns.

Match the columns.

Match the columns.

Write the name.

Products obtained when sugar is heated.

Write the name.

The phase in which solid substances are converted into liquid.

Write the name.

The amount of heat absorbed at constant temperature by unit mass of a liquid to convert into gaseous phase.

Write the name.

Conversion of ice into liquid due to applied pressure and the reconverts to ice once the pressure is removed.

Write the name.

The instrument used to study anomalous behaviour of water.

Write the name.

The instrument used to measure the specific heat capacity of a substance using mixture method.

The dew point temperature does not depend on the amount of vapor in the air.

The specific heat capacity of water is 1 cal/g °C.

Right or wrong sentence.

The invisible heat of evaporation is called the conversion of gas into liquid.

Right or wrong sentence.

Use calorimeters to study the inconsistent behaviour of water.

During reheating, ice is converted to water at a temperature of 0 °C.

1 kg of dry air at a temperature of 40 °C can hold a maximum of 49 g of water vapour.

Right or wrong sentence.

Calorimeters are used to measure specific calorific value.

All metals have the same specific heat capacity.

Humidity relative to dew point temperature is 100%.

The unit of absolute humidity is kg/m³.

1 calorie is 4.81 joules.

In cold regions, in winter the pipes for water supply break.

Write scientific reason.

Even if boiling water is constantly heated, its temperature does not rise.

Write scientific reason.

Use a pressure cooker to cook food in cold air.

Write scientific reason.

In the cold regions, snow falls in winter.

Write scientific reason.

The bottom of some steel utensils used for cooking is copper.

Drops of water can be seen accumulating on the glass of vehicles in the early hours of winter.

Write scientific reason.

During winter season, we may have observed a white trail at the back of the aeroplane flying high in the clear sky or sometimes it may not get formed.

Write scientific reason.

Fish can survive even in frozen ponds in cold regions.

Write scientific reason.

Placing a plastic bottle filled with water in the freezing compartment in the freezer can cause the bottle to explode.

Write scientific reason.

Even the wire moves through the ice slab , the ice slab does not break.

Draw a neat and labelled diagram of Hope’s apparatus.

Name the following diagram appropriately.

Observe the following diagram and write the answers to the questions given below.

1. Which process does the graph represent?
2. What is the range of temperature responsible for the behaviour?

Find the amount heat needed needed to raise the temperature of a piece of iron of mass 500gby 20C. (c=0.110cal/g.C)

If water of mass 60 g and temperature 60 ˚C is mixed with water of mass 60 g and temperature 40 ˚C, what will be the maximum temperature of the mixture?

Find the amount of heat needed to raise the temperature of a silver container of mass 100 g by 10°C. (c = 0.056 cal/gT)

Write a short note.

Anomalous behaviour of water

Write a short note.

Specific heat capacity

Write a short note.

Dew point temperature

Write a short note.

Regelation

Which principle is used to measure the specific heat capacity of a substance?

Decide the unit for specific heat capacity.

Explain the following:

In cold regions in winter, the rocks crack due to anomalous expansion of water.

Explain how heat capacity of a solid can be determined by the method of mixture.

What is meant by latent heat?

How will the state of matter transform if latent heat is given off?

What is the role of the anomalous behaviour of water in preserving aquatic life in regions of cold climate?

Explain the following:

How can you relate the formation of water droplets on the outer surface of a bottle taken out of the refrigerator with the formation of dew?

Geeta observed a white trail at the back of aeroplane in a clear sky to answer the question from this incident given below.

1. What will be the effect of relative humidity of the air surrounding the plane?
2. What will be the effect of relative humidity of the air surrounding the plane is low?
3. When the air is dry and humid?

Observe the given picture and answer the following questions.

1. Which property do you understand in this picture?
2. What is the temperature of the water at the surface?
3. What is the temperature below the layer of ice on the surface?

Read this activity and answer the following questions.

1. Take three spheres of iron, copper and lead. the lead of equal mass.
2. Put all the three spheres in boiling water in the beaker for some time.
3. Take the three spheres out of the water.
4. All the spheres will be at a temperature 100 °C.
5. Put them immediately on the thick slab of wax.
6. Note, the depth that each of the sphere goes into the wax.

Questions:

1. Which property is determined from this activity?
2. Give name to that property.
3. Explain the term principal of heat exchange with the help of this activity.

The cold object the hot object enclosed in one box of heat-resistant material.

1. What changes will occur in the two objects when temperature flows from those objects?
2. Which principle can show that the energy exchange takes place between two objects only when kept in isolated system?

Read the passage and answer the questions based on it.

If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both objects attain the same value. In this process, the cold object gains heat energy and the hot object loses heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat-resistant box then no energy can flow from inside the box or come into the box. In this situation, we get the following principle.
Heat energy lost by the hot object = Heat energy gained by the cold object. This is called the ‘Principle of heat exchange’.

1. Where does heat transfer take place?
2. In such a situation which principle of heat do you perceive?
3. How can this principle be explained in short?
4. Measuring the property of which substance this principle is used?

Explain the following temperature vs time graph.