
A planet moves around the sun in nearly circular orbit. It's the period of revolution ‘ ’ upon i) radius ‘ ’ of the orbit ii) Mass ‘ ’ of the sun and iii) gravitational constant ‘ ’. Show dimensionally that .
Answer
404.7k+ views
2 likes
Hint: Law of Gravitation – Every object in the universe attract other object along the line of center for two objects that is proportional to the product of their masses and inversely proportional to the square of the separation between the two objects.
Complete step by step answer:
According to the law of Gravitation,
where is the gravitational force, is the mass of the sun, is the mass of the planet, is the distance between the sun and the planet.
It is stated that the planet moves round the sun in a nearly circular orbit.
Let ,
…(i) where is a dimensionless constant. The dimensions of various quantities are-
, ,
By substituting these dimensionally in equation (i), we get
Equating the dimensions,
, ,
On solving,
, ,
Squaring both sides,
.
Note:
Planets revolve in elliptical orbits around the sun. It is closest to the sun at perihelion and farthest from the sun at aphelion.
Applying Kepler’s Third Law – We assume that the planets revolve in circular orbits around the sun.
where is the centripetal force and is the gravitational force. The centripetal force arises due to the gravitational force.
where is the velocity with which the planet moves in an orbit around the sun.
where is the time period.
Squaring both sides,
Complete step by step answer:
According to the law of Gravitation,
It is stated that the planet moves round the sun in a nearly circular orbit.
Let ,
By substituting these dimensionally in equation (i), we get
Equating the dimensions,
On solving,
Squaring both sides,
Note:
Planets revolve in elliptical orbits around the sun. It is closest to the sun at perihelion and farthest from the sun at aphelion.
Applying Kepler’s Third Law – We assume that the planets revolve in circular orbits around the sun.
Squaring both sides,
Latest Vedantu courses for you
Grade 10 | MAHARASHTRABOARD | SCHOOL | English
Vedantu 10 Maharashtra Pro Lite (2025-26)
School Full course for MAHARASHTRABOARD students
₹31,500 per year
Recently Updated Pages
Master Class 11 Economics: Engaging Questions & Answers for Success

Master Class 11 Business Studies: Engaging Questions & Answers for Success

Master Class 11 Accountancy: Engaging Questions & Answers for Success

Master Class 11 English: Engaging Questions & Answers for Success

Master Class 11 Computer Science: Engaging Questions & Answers for Success

Master Class 11 Maths: Engaging Questions & Answers for Success

Trending doubts
State and prove Bernoullis theorem class 11 physics CBSE

What are Quantum numbers Explain the quantum number class 11 chemistry CBSE

Write the differences between monocot plants and dicot class 11 biology CBSE

Who built the Grand Trunk Road AChandragupta Maurya class 11 social science CBSE

1 ton equals to A 100 kg B 1000 kg C 10 kg D 10000 class 11 physics CBSE

State the laws of reflection of light
