Question

Fill in the blanks with correct word to make the following statement
'True'. (Each correct answer - 1 mark)
1.
The ratio of the magnitude of average velocity to average speed
is.........
During summer, water kept in an earthen pot becomes cool
because of the phenomenon of..........
3. Alloy is mixture of .........
........ is not found in xylem tissues.
2.​

Answer 1

Answer:

1. less than or equal to one.

2. evaporation

3. two or more metals or a metal and a non metal

4. Medullary rays

Answer 2

The blanks are filled with correct word to make the following statement correct:

1. The ratio of the magnitude of average velocity to average speed is never greater than one.

• Velocity can be equal to the speed or it is less than the speed. But, it can not be greater than speed.
• This is why the ratio of velocity to speed will either be equal to one or less than one.

2. During summer, water kept in an earthen pot becomes cool because of the phenomenon of evaporation.

• Earthern pots have numerous minute pores in them.
• Water continuously escapes from these pores as vapour due to evaporation.
• The heat required for the water to convert into vapour is obtained from the remaining water in the pot.
• As a result, the temperature of the water in the earthen pot is lowered and the water becomes cool.

3. Alloy is mixture of two metals or a metal and non-metal.

• Alloy can be composed of two metals as in brass or a metal and a non-metal as in steel.
• Brass is formed of copper and zinc while steel contains iron and carbon.

4. Sieve tube elements and companion cells are not found in xylem tissues.

• Xylem is composed of tracheids, vessels, xylem fibres and xylem parenchyma.
• While phloem is composed of sieve tube elements, companion cells, phloem fibres, and phloem parenchyma.