Why the hair of a painting brush stick together when taken out of water ?
Because the free surface of water tends to contract.
Because the cohesive force between the molecules of water more in air than in water.
Because the water glues the hair together.
Because the adhesive force between the molecules of water and the molecules of hair is very strong.
Nutritional requirements of a population can be estimated easily by
diet surveys of normal healthy people.
methods involving laboratory animals.
Why is it more comfortable to swim in sea water than in river ?
Becanse sea water is warmer than the river water.
Because sea water is salty.
Because the density of sea water is more than that of river water.
Because sea is much deeper than river.
When a bicycle tube is pumped up, the bicycle pump gets heated. Which of the following is the cause of production of this heat energy ?
Transformation of mechanical energy spent in compressing the air particles against the pressure of air inside.
Transformation of mechanical energy spent in overcoming friction.
Both of these.
None of these.
Why steam causes more severe burns than boiling water ?
Because steam contains a greater amount of heat.
Because the temperature of steam is more than that ~off bboiling water.
Both of these.
None of these.
Which of the two will flow more rapidly down a channel of given slope, mercury or water ?
Mercury will flow more rapidly.
Water will flow more rapidly.
Both mercury and water will take the same time.
It will depend on the material of which the channel is built Of.
A well nourished infant.
doubles its body weight by the end of six months of age.
triples its body weight by the end of one year.
both (o) and (b) -
none of these.
Why does a dead body float in water after some time ?
Because all the gases of the body leave it thus making it lighter than water.
Because the dead body bursts open and becomes lighter than water.
Because the dead body begins to emit foul smelling gases which lift the dead body to the surface of the water. '
Because the dead body swells and becomes lighter than water.
Why does the pressure of air in tyres increase when the vehicle is set in motion 'I
The rotatory motion of the wheels of the vehicle contributes to this increase in pressure.
When the vehicle is in motion, the molecules of the air in the tyres acquire more kinetic energy. This increase in kinetic energy is responsible for the increase in pressure.
Because the tyres suffer a slight contraction when they are in motion.
The temperature increases, air in the tyres expands. . Therefore, there is a slight increase in the pressure of air.
A smoked metal ball, when dipped in water appears to shine brightly. Which of the following phenomena of light is responsible for this ?
Total internal reflection.
Rectilinear propagation of light.
1. World Geography -Test-01
2. World Geography -Test-02
3. World Geography -Test-03
4. Geography of India -Test-01
5. Geography of India -Test-02
6. Geography of India -Test-03
7. Geography of India -Test-04
8. Geography of India -Test-05
9. History of India - Test - 01
10. History of India - Test - 02
11. History of India - Test - 03
12. History of India - Test - 04
13. History of India - Test - 05
14. History of India - Test - 06
15. History of India - Test - 07
Simple Tips To Living Longer
Unstable Countries In The World
Hand Embroidery Designs
Wildlife Sanctuaries and National Parks of India
Benefits of Black berries
Benefits of Nutmeg
Tips to get ready for Foreign Trip
Bring a travel first aid kit
ibuprofen (or other pain killer), decongestant, NyQuil, bandages, hydrocortizone cream. You will not believe how often it will come in handy.