These TS 7th Class Science Important Questions 5th Lesson Heat-Measurement will help the students to improve their time and approach.
TS 7th Class Science Important Questions 5th Lesson Heat-Measurement
Question 1.
Write the differences between heat and temperature.
Answer:
| Heat | Temperature |
| 1. The energy which makes an object appear hot or cold is called heat. 2. Heat is the cause 3. It is measured in calories 4. It is measured with calorimeter |
1. Temperature is the measure of the degree of hotness or coldness of an object. 2. Temperature is the effect. 3. It is measured in degrees 4. It is measured with thermometer. |
Question 2.
Compare the properties of mercury and water.
Answer:
| Mercury | Water |
| 1. It is a metal. 2. It is opaque and shining. 3. Its expansion is uniform. 4. It is a good conductor of heat. |
1. It is a non-metal. 2. It is transparent. 3. Its expansion is non-uniform. 4. It is a bad conductor of heat. |
Question 3.
Write the properties of alcohol as thermometric liquid.
Answer:
- Alcohol can record very low temperatures.
- Its expansion per degree celsius rise in temperature is very large.
- It can be coloured brightly and hence is easily visible.
Question 4.
Describe the structure of clinical thermometer.
Answer:
- Clinical thermometer Consists of a bulb of very thin glass and capillary tube.
- Bulb is filled with pure mercury.
- This capillary tube consists a kink, which prevents mercury level from falling on its own.
- It is marked from 35°C to 45°C in celsius scale and 95°F to 110°F is Fahrenheit scale.
Question 5.
Explain the types of thermometers and their uses.
Answer:
1. Clinical thermometer:
Use: Doctors use it to find out the temperature of our bodies.
2. Thermister thermometer:
Use: It is used to measure the human body temperatures, particularly for infants and children.
3. Digital thermometer:
Use: It is used to measure the human body temperature accurately.
Mercury is not used in this.
4. Laboratory thermometer:
Use: It is used to measure temperature of liquids and objects.
Question 6.
Define ‘temperature’:
Answer:
Temperature is the degree of hotness or coldness of an object.
Question 7.
Fame some questions on Heat-measurement.
Answer:
- Why should we measure heat?
- How heat influences the weather?
- How heat shows its capacity in various sectors?
- Is heat considered the energy resource?
Question 8.
What would happen to clinical thermometer if it is kept in the water that is heated upto 50°C.?
Answer:
Clinical thermometer has the capacity to measure the temperature only upto 45°C of any heated object. If it is kept in the hot water of 50°C, the thermometer cannot withstand that heat and ultimately the bulb of thermometer will break.
Question 9.
When rice is being cooked you can observe the plate jumps on the rice bowl. What concepts do you learn through this observation?
Answer:
Boiled water is being converted to water vapour. The volume of water vapour increases. The increasing volume of vapour tries to go out. In this process the heat in the form of energy lifts the lid up.
Question 10.
How can you prove expansion of liquids on heating?
Answer:
Aim : To prove expansion of liquid due to heat.
Apparatus required : Flat bottom flask, one-holed rubber cork, capillary tube, coloured water, metal trough.
Procedure: A flat bottom flask is taken and filled with coloured water. A cork having a capillary tube is fixed, in the mouth of flask such that the level of water is shown as the flask is placed in a metal trough. Pour boiling water into the trough and carefully observe the level of coloured water.
Observations: Level of coloured water in capillary tube increases.
Result: Liquids expand on heating.
Question 11.
Write the observation you made in the readings of clinical as well as laboratory thermometers.
Answer:
In clinical thermomters, the Fahrenheit reading is from 95°F to 110°F on one side of the capillary tube.
Otherside of the capillary tube has contigrade readings from 35°C to 45°C. In laboratory thermometer, the readings are from —10°C to 100°C.
Question 12.
Observe the diagram and write your answer.
1. What is the name of this instrument?
2. Liquid present in the instrument?
3. Write the names of A, B and C.
4. What do you do with this instrument?
Answer:
1. Clinical thermometer.
2. Mecury
3.
- Mercury bulb
- construction
- capillary tube.
4. We can measure the body temperature.
Question 13.
Read the paragraph given below. Answer the following questions.
We know that heat is a form of energy that is transferred from an object at higher temperature to the one at lower temperature. When we stand in the sun or near fire, heat energy enters our body and we feel hot. When ice is put on our palm, heat energy moves from our body to the piece of ice.
i. At what circumstances heat is transferred?
Answer:
Heat is transferred from an object at higher temperature to one at lower temperature.
ii. Give an example for transfer of heat energy which occurs in our daily life.
Answer:
When we stand in the sun or near fire, heat energy enters our body and we feel hot.
iii. Heat transfers from one object to another. Hence it is commonly considered what?
Answer:
Heat is a form of energy.
Question 14.
Ganesh recorded the maximum temperature at his village for 5 days in the table.
Answer:
| Day | Date | Max. temperature |
| 1 | 14.05.2018 | 32° |
| 2 | 15.05.2018 | 31° |
| 3 | 16.05.2018 | 31° |
| 4 | 17.05.2018 | 34° |
| 5 | 18.05.2018 | 31° |
Answer the following questions:
1. When was the maximum temperature recorded?
Answer:340 Con 17.05.2018.
2. When was the minimum temperature recorded?
Answer: 31° Con 15.05.2018, 16.05.2018 and 18.05.2018.
3. On which days the temperature was same?
Answer: 15, 16 and 18th of May.
4. Guess what would be the temperature on 6th day?
Answer: More or less.
Question 15.
What is the use of Six’s maximum-minimum thermometer? Draw it and label its parts.
Answer:
The maximum and minimum temperatures of a day are measured by a thermometer called the Six’s maximum minimum thermometer.
Question 16.
Observe the diagram and name the indicated parts and write its use.
Answer:
This is clinical thermometer.
- Constriction
- Mercury bulb
- Capillary tube
- Normal temperature of human body
- Triangular stem
Use : It is used to measure the body temperature.
Question 17.
Observe the diagram and name the indicated parts.
Answer:
This is laboratory thermometer.
Question 18.
Write the advantages of heat energy in our daily life.
Answer:
- We cook food by using heat energy.
- Heat energy emitted from the sun is used as solar power.
- Heat is utilised in boiler for boiling water.
Question 19.
Name some devices or appliances which convert other sources of energy into heat energy.
Answer:
- Water heater boils the bathing water by converting electrical energy into heat energy.
- Cooking stove receives chemical energy from gas and converts it into heat energy.
Choose the correct answer:
I. Conceptual Understanding
Question 1.
Melting point of ice. ( )
A) 0°C
B) 37°C
C) 50°C
D) 100°C
Answer:
A) 0°C
Question 2.
Boiling point of water ( )
A) 0°C
B) 37°C
C) 50°C
D) 100°C
Answer:
D) 100°C
Question 3.
In which season, temperature is very high? ( )
A) Winter
B) Rainy
C) Summer
D) Spring
Answer:
C) Summer
Question 4.
In the following, which is the good conductor of heat? ( )
A) Mercury
B) Water
C) Wood
D) Thermocol
Answer:
A) Mercury
Question 5.
The range of temperature in clinical thermometer is ( )
A) 0°C – 100°C
B) 35°C – 45°C
C) 0°C – 37°C
D) 25°C – 35°C
Answer:
B) 35°C – 45°C
Question 6.
………….. prevents mercury level from falling on its own in a clinical thermometer. ( )
A) Capillary tube
B) hook
C) Stem
D) Kink
Answer:
D) Kink
Question 7.
In the following, which is thermometric liquid ? ( )
A) Water
B) Kerosene
C) Mercury
D) Salt water
Answer:
C) Mercury
Question 8.
First thermometer was invented by ( )
A) Newton
B) Galileo
C) Copernicus
D) Cavendish
Answer:
B) Galileo
Question 9.
The normal temperature of human body. ( )
A) 34°C
B) 35°C
C) 36°C
D) 37°C
Answer:
D) 37°C
Question 10.
In the following thermometers, which does not contain mercury?
A) Digital
B) Clinical
C) Laboratory
D) Six’s maximum – minimum
Answer:
A) Digital
II. Asking Questions and Making Hypothesis
Question 11.
Boiling point : 100°C :: melting point : …. ? ( )
A) 0°C
B) 30°C
C) 50°C
D) 100°C
Answer:
A) 0°C
Question 12.
Find the odd one out. ( )
A) Six’s minimum – maximum thermometer
B) clinical thermometer
C) Digital thermometer
D) laboratory thermometer
Answer:
C) Digital thermometer
Question 13.
The boiled water at 100°C is tested with clinical thermometer. Then the instrument ( )
A) detects the temperature
B) is broken
C) finds out boiling point
D) all the above
Answer:
B) is broken
Question 14.
Thermometer works on the principle ( )
A) matter contracts on heating
B) matter detaches on heating
C) matter spreads on heating
D) matter expands on heating
Answer:
D) matter expands on heating
Question 15.
Before using clinical thermometer, we should ( )
A) move it for working
B) jerk it to adjust the mercury
C) jerk it to adjust the temperature
D) expand it to adjust the mercury
Answer:
B) jerk it to adjust the mercury
Question 16.
Rubbing your palms generates ( )
A) rubbing energy
B) smooth energy
C) heat energy
D) kinetic energy
Answer:
C) heat energy
Question 17.
The apparatus used for showing the experiment that liquids expand on heating is ( )
A) cork
B) capillary tube of thermometer
C) water
D) all the above
Answer:
V. lnformatíon Skills and Projects
Question 18.
One of the following home appliances is not used as heat generating one ( )
A) Tea flask
B) Iron box
C) Stove
D) Water heater
Answer:
A) Tea flask
Question 19.
This is not useful as clinical thermometer ( )
A) Digital thermometer
B) Thermister thermometer
C) Lab thermometer
D) A and B
Answer:
C) Lab thermometer
Question 20.
The following belongs to heat occurrence ( )
A) fire damp in winter
B) standing in the sun
C) rubbing hands
D) all the above
Answer:
D) all the above
VI. Communication through Drawing and Model Making
Question 21.
The given picture is (i) ……………. and it is used for (ii) ……………. ( )
A) i – Diabetic thermometer, ii – children and infants
B) i – thermister thermometer, ii – children and infants
C) i – thermister thermometer, ii – adults and infants
D) i – Digital thermometer, ii – infants and old people
Answer:
B) i – thermister thermometer, ii – children and infants
Question 22.
In the given picture of clinical thermometer name the part that is indicated as number – 4 ( )
A) Constriction
B) Mercury bulb
C) Capillary tube
D) Reading
Answer:
D) Reading
Question 23.
The given picture shows the experiment that proves ( )
A) liquids expand on cooling
B) liquids contract on heating
C) liquids expand on heating
D) liquids contract on cooling
Answer:
C) liquids expand on heating
VI. Application to Daily Life and Concern to Bio Diversity
Question 24.
Only because of this, solar power plants are established ( )
A) tire furnaces
B) sun light
C) rains
D) winds
Answer:
B) sun light
Question 25.
The purpose of laboratory thermometer is to measure the temperature of ( )
A) liquids
B) solids
C) gases
D) A, B and C
Answer:
D) A, B and C
Question 26.
This is advisable regarding use of clinical thermometer ( )
A) It is not for measuring objects
B) k is to be kept away from sun light
C) It should not be brought near flame
D) All are correct
Answer:
D) All are correct
Question 27.
The constant temperature at which ice melts is called of ice. ( )
A) Boiling point
B) Melting point
C) Freezing point
D) All the above
Answer:
B) Melting point
Question 28.
The constant temperature at which water starts boiling is called of water. ( )
A) Boiling point
B) Melting point
C) Freezing point
D) Latent point
Answer:
A) Boiling point