Chemistry # A. Answer the following in not more than 20 words.1. Give one example to show that heat is a form of energy.2. What is temperature? Name the scales used to measure it.3. If the hotness or coldness of a body is relative, how do we measure its degree of hotness?4. Mention three changes that heat causes in substances.5. A steel spoon dipped in a pot of boiling soup for a few minutes becomes too hot to touch. Howdoes heat travel through the spoon?6. How is it that we can hold a match while it is burning?7. How does turning on a heater in a room make the whole room warm?8. How does heat from the sun reach the earth?9. Mention one similarity between heat and light.10. When two bodies are in contact, heat flows from the hotter to the colder body. When does heastop flowing?

1= heat is a from of energy which produces a sensation in our body by way of which we make out whether a body is cold,warm or hot. ex: solar energy and tidal energy

2= There are 3 temparature scales in use (I)= Fahrenheit,( b)= celcius and (3)= Kelvin. Fahrenheit temparature scales is a scale based on 32 for the boling point of water, the interval between the two being divided into 180 parts.

(3)= we measured the hotness or coldness of a body by measuring its temparature and comparing with standard temparature scales.

(4)= 1= change in state, 2= change in temperature, 3= change the length of the object

5= heat travel through the spoon in the process of conduction in the process of conduction heat is transferred through solid so spoon is solid and good conducter of heat.

6= we can hold match while it is burning as we hold only the wooden part of the matchstick. wood is bad conductor of heat and does have wavelength and frequency.

7= when high voltage is passed it produce a large amount of heat the blowser situated in the heater blows this heat which diffuse in the room to make the room hot.

8= The sun heats the earth through radiations.since there is no medium ( like the gas in null our atmosphere) in space radiations is the primary way that heat travels in space.

9= light and heat, both are froms of energy and this energy is acquired from the sun which is the ultimate source of energy.one more similarity is,both light and heat have wavelength frequency

10= The heat stop flow when same quantity of heat will remain in both the bodies.it means equal heat will be in both the bodies.

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