Advertisements
Advertisements
प्रश्न
Give an example of a constant which has no unit.
उत्तर
Reynold's number is a constant which has no unit.
APPEARS IN
संबंधित प्रश्न
The volume of a cube of side 1 cm is equal to ______ m3
The surface area of a solid cylinder of radius 2.0 cm and height 10.0 cm is equal to ______ (mm)2.
A vehicle moving with a speed of 18 km h–1covers ______ m in 1 s.
Explain this statement clearly:
“To call a dimensional quantity ‘large’ or ‘small’ is meaningless without specifying a standard for comparison”. In view of this, reframe the following statements wherever necessary:
- Atoms are very small objects
- A jet plane moves with great speed
- The mass of Jupiter is very large
- The air inside this room contains a large number of molecules
- A proton is much more massive than an electron
- The speed of sound is much smaller than the speed of light.
A new unit of length is chosen such that the speed of light in vacuum is unity. What is the distance between the Sun and the Earth in terms of the new unit if light takes 8 min and 20 s to cover this distance?
A famous relation in physics relates ‘moving mass’ m to the ‘rest mass’ m0 of a particle in terms of its speed v and the speed of light, c. (This relation first arose as a consequence of special relativity due to Albert Einstein). A boy recalls the relation almost correctly but forgets where to put the constant c. He writes:
`m = m_0/(1-v^2)^(1/2)`
Guess where to put the missing c.
Fill in the blank by suitable conversion of unit:
1 kg m2s–2= ______ g cm2 s–2
Fill in the blank by suitable conversion of unit:
G= 6.67 × 10–11 N m2 (kg)–2= ______ (cm)3s–2 g–1
Young’s modulus of steel is 1.9 × 1011 N/m2. When expressed in CGS units of dynes/cm2, it will be equal to (1N = 105 dyne, 1m2 = 104 cm2)
During a total solar eclipse the moon almost entirely covers the sphere of the sun. Write the relation between the distances and sizes of the sun and moon.
