सामंतवाद का Earth सपषट कीजिए?
Answers
Explanation:
1.
2.
3.
ng questions in brief.
In which direction does the transfer of heat normally take place?
What is the cause of heat generation in the following situations:
(a) We apply brakes on our fast moving car.
(b) People often jump up and down to feel warmer in cold weather.
State two types of physical changes that may take place when a substance is
heated.
In what way(s) does a clinical thermometer differ from an ordinary thermometer?
State the mode/different modes, of heat transfer, in the following situations.
(a) A paper cup, full of hot soup, lying on a table.
(b) Cooking vegetables in a pan.
(c) Melting of a chocolate bar, in the school bag, on a hot day.
4.
5.
(d) Cooking food in a microwave oven.
6.
What is meant by sea breeze? When does it occur?
Kavitha a ten year old girl is very fond of sweets. She eats chocolates and sweets
quite frequently every day. On account of this, she developed problem of tooth
decay with toothache. Her elder brother Akshay, a student of class X, noticed the
problem of his sister and advised her not to take much sweets. He also advised her
to clean her teeth with tooth paste twice daily. Kavitha followed the advice of her
elder brother and started cleaning her teeth with the tooth paste in the morning
before meal and in the night after the meal. The condition of her teeth improved
day by day.
Answer the following questions
a) Why did Kavitha develop tooth decay and toothache?
b) What is the nature of the tooth pastes usually used by us?
c) How does the brushing of teeth after meal help in fighting tooth decay?
d) Is it necessary to brush our teeth after eating even when not eating sweets
at all?