Thursday, March 7, 2013

Science quiz by for std of class 6,7 & 8 at BVM eroor-Round5(Answer as cmnts)

Ans:1.Hard water
2.Multiple reflection
3.Vaccum-Non conducting
6.Air Pressure

1 comment:

Iyer said...

1. Hard Water
2. A Kaleidoscope operates on the principle of MULTIPLE REFLECTION, where several mirrors are placed at an angle to one another, usually 60°.
3. The flask consists of an inner and outer chamber, the space between the chambers is a vacuum.?
4. Egg 1 - The raw egg's centre of gravity changes as the white and yolk move around inside the shell, causing the wobbling motion. Even after you touch the shell it continues moving. This is because of inertia, the same type of force you feel when you change direction or stop suddenly in a car, your body wants to move one way while the car wants to do something different. Inertia causes the raw egg to spin even after you have stopped it, this contrasts with the solid white and yolk of the hard boiled egg, it responds much quicker if you touch it.
5. Law of Inertia (Newton's First Law of Motion).
6. When you heated the can you caused the water in it to boil. The vapor from the boiling water pushed air out of the can. When the can was filled with water vapor, you cooled it suddenly by inverting it in water. Cooling the can caused the water vapor in the can to condense, creating a partial vacuum. The extremely low pressure of the partial vacuum inside the can made it possible for the pressure of the air outside the can to crush it.A can is crushed when the pressure outside is greater than the pressure inside, and the pressure difference is greater than the can is able to withstand. You can crush an open aluminum can with your hand. When you squeeze on the can, the pressure outside becomes greater than the pressure inside. If you squeeze hard enough the can collapses. Usually, the air pressure inside an open can is the same as the pressure outside. However, in this experiment, the air was driven out of the can and replaced by water vapor. When the water vapor condensed, the pressure inside the can became much less than the air pressure outside. Then the air outside crushed the can.