The Total solution for NCERT class 6-12
Explain this statement clearly:
“To call a dimensional quantity ‘large’ or ‘small’ is meaninglesswithout specifying a standard for comparison”. In view of this, reframe thefollowing statements wherever necessary:
(a) atoms are very small objects
(b) a jet plane moves with great speed
(c) the mass of Jupiter is very large
(d) the air inside this room contains a large number of molecules
(e) a proton is much more massive than an electron
(f) the speed of sound is much smaller than the speed of light.
The given statement is true because a dimensionless quantity maybe large or small in comparision to some standard reference. For example, thecoefficient of friction is dimensionless. The coefficient of sliding frictionis greater than the coefficient of rolling friction, but less than staticfriction.
(a) An atom is a very small object in comparison to a soccer ball.
(b) A jet plane moves with a speed greater than that of a bicycle.
(c) Mass of Jupiter is very large as compared to the mass of acricket ball.
(d) The air inside this room contains a large number of moleculesas compared to that present in a geometry box.
(e) A proton is more massive than an electron.
(f) Speed of sound is less than the speed of light.