Page 40 - Science Class 07

B. Fill in the blanks.
1. _______ is a measure of the average heat or thermal energy of the par cles in a substance.

2. The heat that a body possesses is directly related to ___________ energy.
3. The ___________ to kine c energy involved, the ho er the body is.
4. We can know the hotness of a body with the help of a ___________ .

5. The Kelvin scale was designed by ___________ in 1848.
6. ___________ can take place in vacuum as well as in air.
C. Write True or False.
1. Heat energy can be transformed in other form of energy.

2. When an object is heated the molecules present in it start moving or vibra ng.
3. All the objects on the earth have certain amount of heat.
4. The celsius scale is divided into 100 equal parts.

5. Convec on takes place in liquid and gases.
D. Very short answer ques ons.
1. What happens when we heat water?
2. Who discovered that heat can be transformed into mo on?
3. Why cannot we define cold?
4. What do you mean by temperature?
5. Name any three scales of temperature measurement.
6. Name any three ways through which heat is transferred.

7. What is radia on?
8. Why the inner wall of the bo le in a thermos flask has silver coa ng?
E. Short answer ques ons.
1. Describe any two scales of temperature measurement.
2. What is a clinical thermometer?
3. What is conduc on?
4. Differen ate between conductors and insulators.

F. Long answer ques ons.
1. What do you understand by heat? Explain.
2. Write the structure of thermometer.
3. Write a short note on convec on.
4. Write about the construc on and working of a thermos flask.

Project
Project
Project ActivityActivityActivity
Project Activity
Take a clinical thermometer and measure the body temperature of your family members and note
down on a paper. Before taking temperature you should shake the thermometer properly.

HOTSTSTS
HO
HO
HOTS
A. Why do people wear white clothes in summer while black in winter?
B. Why a gap is le between two consecu ve iron lining of the railway track.

40 Science-7