Physics Urgent!!!!!

Mars orbits the Sun at a mean distance of 228 million km, in a period of 687 days. The Earth orbits at a mean distance of 149.6 million km in a period of 365.26 days. All answers should be in the range (0, 2pi)
a) Suppose Earth and Mars are positioned such that Earth lies on a straight line between Mars and the Sun. Exactly 365.26 days later, when the Earth has completed one orbit, what is the angle between the Earth-Sun line and the Mars-Sun line? (in rad)
b) The initial situation in part a) is a closest approach of Mars to the Earth. What is the time between 2 closest approaches? Assume constant orbital speeds and circular orbits for both Mars and Earth. (Hint: when angles are equal) (in days)
c) Another way of expressing the answer to part (b) is in terms of the angle between the line drawn through the Sun, Earth, and Mars in the two closest approach situations. What is that angle? (in rad)


Physics (please help!!!!) - drwls, Friday, April 8, 2011 at 2:12am
a) When Earth has travelled one orbit, Mars will have completed 365.2/687 = 53.2% of an orbit. Mars will be 46.8% of an orbit behinbd Earth. Convert that to radians.

b) Extrapolate to find out how long it takes for Mars to fall 360 degrees behond Earth. That is when a new alignment will occur.

c) Figure out how far (in angle) Earth travels between alignments. It will be more than two complete revolutions. You only want the additional angle beyond two revolutions. (Use the time from part (b)). Convert that to radians.

For part A I got 2.94 rad, not sure if that's right... I still don't get part b... I just used the initial distance I got for Mars after 365.25 days and then multiplyed it by 3 and I got 363 days... I don't think that makes sense... I can't solve part c without part b.

  1. 👍
  2. 👎
  3. 👁
  1. Ok I got the 2 first ones right... 2.94 and my new value for b is 777.... I still cant get the last one, I thought that by multiplying Mars' angular speed and the time I got for part A that was going to be the answer.. I got 7.11 rad but that's wrong....

    1. 👍
    2. 👎
  2. If I substract 2pi from 7.11 I get 0.83... will that be the angle???

    1. 👍
    2. 👎
  3. But 7.11 is just more thatn one complete revolution, then that's not the right anwer?

    1. 👍
    2. 👎
  4. Oh wait, I was using the angular speed of Mars, using the angular speed of Earth I get 13.4 radians and that will be more than two revolutions so the additional angle is 0.798 rad? Is that right?? Please someone answer...

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Science

    In a drawing that represents a scale model of the solar system, the sun is placed at the center and the planets are shown orbiting in circles around it. While in reality Mars is 1.5 AU away from the sun, in the model Mars appears

  2. science

    Solar System Distances Quick Check Question Use this paragraph: In a scale model of the solar system, the sun is placed at the center and the planets are shown orbiting in circles around it. Mars is 1.5 AU away from the sun and in

  3. Physics

    Mars, on average, is 140 million miles from the Sun. 1 mi = 1609 m . Part #1: Express the distance between Mars and the Sun in meters using powers of 10. Express your answer using two significant figures. Answer: d =2.25×10^11 m

  4. Math

    One of Kepler's three laws of planetary motion states that the square of the period, P, of a body orbiting the sun is proportional to the cube of its average distance, d, from the sun. The Earth has a period of 365 days and its

  1. Astro

    A newly discovered planet orbits a distant star with the same mass as the Sun at an average distance of 118 million kilometers. Its orbital eccentricity is 0.5. A.Find the planet's orbital period. B.Find the planet's nearest

  2. Physics

    Halley’s comet orbits the Sun with a period of 76.2 years. a) Find the semi-major axis of the orbit of Halley’s comet in astronomical units (1 AU is equal to the semi-major axis of the Earth’s orbit Physics - drwls,

  3. Science

    In a drawing that represents a scale model of the solar system, the sun is placed at the center and the planets are shown orbiting in circles around it. While in reality Mars is 1.5 AU away from the sun, in the model Mars appears

  4. Math

    The period of revolution of a planet around the sun is the time it takes for the planet to complete one orbit of the sun. The period, P years, is give by Kepler's third law P^2=D^3, where D is the average distance from the sun in

  1. Astronomy

    Venus orbits 0.72 AU from the sun. What is that distance in kilometers?

  2. Math

    One of Kepler's three laws of planetary motion states that the square of the period, P, of a body orbiting the sun is proportional to the cube of its average distance, d, from the sun. The Earth has a period of 365 days and its

  3. Astronomy

    The average distance between the Earth and the Sun is called the astronomical unit (AU), which is about 150 million km (1.5 x 108 km). Jupiter is 780 million km from the sun. a) How far is Jupiter from the sun in astronomical

  4. science

    If Earth is 149.6 million Kilometers from the sun, or 93 million miles away. suppose there was an imaginary road from earth to the sun. If you were in a car traveling 100 km an hour, it would take you 1,490,000 hours or just 170

You can view more similar questions or ask a new question.