The refrigerator has a freezer near its top. This is because the frezeer at the top makes the air near it cool. The cold air being more dense, comes down, while the less dense warm air rises from the lower part. Thus the convection currents formed in a refrigerator keeps the lower part of the refrigerator cool. . . .
If a moving body travels unequal distance in equal intervals of time, its motion is said to be non-uniform. . . .
If a moving body travels equal distance in equal intervals of time, its motion is said to be uniform motion. Thus for the uniform motion, the speed of the moving body remains constant. . . .
A drill used by a carpenter has both the rotatory as well as the translatory motions Carpenter's saw has the translatory as well as the oscillatory motion, as it moves down while oscillating A ball rolling on the ground has the rotatory motion as well as the translatory motion as it moves on the ground. The earth rotates about its axis (rot . . .
A body can have more than type of motion. Such a motion is called mixed motion. Example: The wheels of a moving train have both the translatory as well as the rotatory motions. . . .
The motion which does not repeat itself after the regular interval of time is called non-periodic motion. Example: A footballer running on a field Application of breaks in a moving vehicle A ball rolling down the ground gradually slows down and finally stops. motion of tides in the sea. . . .
A motion which gets repeated after a regular interval of time is called the periodic motion Example: The earth completes one round about the sun in nearly 365 days and this motion is repeated after every 365 days. The moon revolves around the earth and completes one round in nearly 27 days and then repeats its motion. For a normal person he . . .
It is also an oscillatory motion with the difference that in vibratory motion, A part of the body always remains fixed and the rest part moves to and fro about its mean position. During the vibratory motion, the shape and size of the body changes. Examples: When we breath, our chest expands and contracts. This motion is the vibratory motion. . . .
The to and fro motion of a body from its rest position (or mean position) is called the oscillatory motion. Example: The motion of a swing. The motion of the pendulum of a wall clock represent the oscillatory motion In this motion , the bob of pendulum from its rest position moves to one side, comes back to th . . .
Ariel modifications of stem Certain stems modify aerially to perform various functions. Tendril (for support) : stem forms thread like leafless branch called tendril. It coils around any object near it and helps the plant to climb up. Ex. Grapevine, gourd. Thorn (for protection) : stem modified into hard, point like small structure called th . . .
Sub aerial modification of stem Some stems which are weak and green grow horizontally on the surface of soil. Runner- it is soft, thin slender branch which creeps on ground. Ex. Doob grass and wood sorrel. Stolon- it grows upward above the ground to some distance, then bend down to the ground. Ex. Mint, wild strawberry Offset- it is li . . .
A body is said to be in rotatory motion. If it moves about a fixed axis Example: The blades of a fan A spinning top A spinning wheel or a potter's wheel A merry-go-round rotation of the earth about its own axis A rotatory motion is different from a translatory motion, because in rotatory motion, different parts of the obj . . .
The motion of a body along a circular path is called circular motion. Circular motion is a special type of curvilinear motion in which the distance of a moving object from a fixed point(called the centre) does not change. example: Motion of a car around a circular path Motion of earth around the sun Motion of moon around the earth . . .
If a motion of a body is along a curved path it is said to be the curvilinear motion example: The motion of a cycle while taking a turn on the road. A car moving along a curved path. . . .