Advertisements
Advertisements
Question
State Kepler's law of orbit and law of equal areas.
Advertisements
Solution 1
Ist law ( Law of orbit ) : The orbital path in the solar system is an ellipse with sun as one focus.
2nd law ( Law of equal area ) : The radius vector joining the centre of the planet to the centre of sun traces out equal area in equal intervals of time.
i.e.The area velocity of the planet is constant
Solution 2
All planet revolves around the sun in the elliptical orbit, the sun as one of its focus.
The line joining sun and planet sweeps the equal area in equal time interval i.e. Areal velocity is constant.
APPEARS IN
RELATED QUESTIONS
Let us assume that our galaxy consists of 2.5 × 1011 stars each of one solar mass. How long will a star at a distance of 50,000 ly from the galactic centre take to complete one revolution? Take the diameter of the Milky Way to be 105 ly
A comet orbits the Sun in a highly elliptical orbit. Does the comet have a constant (a) linear speed, (b) angular speed, (c) angular momentum, (d) kinetic energy, (e) potential energy, (f) total energy throughout its orbit? Neglect any mass loss of the comet when it comes very close to the Sun.
A Saturn year is 29.5 times the earth year. How far is the Saturn from the sun if the earth is 1.50 ×108 km away from the sun?
State Kepler's laws of planetary motion.
Let the period of revolution of a planet at a distance R from a star be T. Prove that if it was at a distance of 2R from the star, its period of revolution will be \[\sqrt{8}\] T.
Identify the law shown in the figure and state three respective laws.

Answer the following question.
State Kepler’s law of the period.
Observe the given figure showing the orbit of a planet moving around the Sun and write the three laws related to it:

The orbit of a planet moving around the Sun
Observe the given figure and answer these following questions.

- What is the conclusion about the orbit of a planet?
- What is the relation between velocity of planet and distance from sun?
- ASB, CSD and ESF relation between areas explain.
The third law of Kepler is also known as the Law of ______.
The earth moves around the sun in an elliptical orbit as shown in the figure. The ratio, `"OA"/"OB"` = x. The ratio of the speed of the earth at Band at A is ______.

Both earth and moon are subject to the gravitational force of the sun. As observed from the sun, the orbit of the moon ______.
If the sun and the planets carried huge amounts of opposite charges ______.
- all three of Kepler’s laws would still be valid.
- only the third law will be valid.
- the second law will not change.
- the first law will still be valid.
If the sun and the planets carried huge amounts of opposite charges ______.
- all three of Kepler’s laws would still be valid.
- only the third law will be valid.
- the second law will not change.
- the first law will still be valid.
The centre of mass of an extended body on the surface of the earth and its centre of gravity ______.
- are always at the same point for any size of the body.
- are always at the same point only for spherical bodies.
- can never be at the same point.
- is close to each other for objects, say of sizes less than 100 m.
- both can change if the object is taken deep inside the earth.
Draw areal velocity versus time graph for mars.
What is the direction of areal velocity of the earth around the sun?
Out of aphelion and perihelion, where is the speed of the earth more and why?
A star like the sun has several bodies moving around it at different distances. Consider that all of them are moving in circular orbits. Let r be the distance of the body from the centre of the star and let its linear velocity be v, angular velocity ω, kinetic energy K, gravitational potential energy U, total energy E and angular momentum l. As the radius r of the orbit increases, determine which of the above quantities increase and which ones decrease.
A satellite is in an elliptic orbit around the earth with aphelion of 6R and perihelion of 2 R where R= 6400 km is the radius of the earth. Find eccentricity of the orbit. Find the velocity of the satellite at apogee and perigee. What should be done if this satellite has to be transferred to a circular orbit of radius 6R ?
[G = 6.67 × 10–11 SI units and M = 6 × 1024 kg]
The maximum and minimum distances of a comet from the Sun are 1.6 × 1012 m and 8.0 × 1010 m respectively. If the speed of the comet at the nearest point is 6 × 104 ms-1, the speed at the farthest point is ______.
How can an ellipse be drawn using pins and thread?
What is at one focus of the elliptical orbit of a planet?
The time taken by a planet to orbit the Sun depends on ______.
