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Two planets A and B are revolving in cir...

Two planets `A` and `B` are revolving in circular orbits around a fixed sun. Time period of the planet `B` is `2sqrt(2)` times that of planet `A`. Find the ratio of solar constant for planet `A` to that of `B`. Neglect gravitational force between the planets.

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To solve the problem, we will follow these steps: ### Step 1: Understand the relationship between time period and radius According to Kepler's third law of planetary motion, the square of the time period \( T \) of a planet is directly proportional to the cube of the radius \( r \) of its orbit around the sun. This can be expressed as: \[ T^2 \propto r^3 \] From this, we can derive the relationship: \[ r \propto T^{2/3} \] ### Step 2: Relate the time periods of planets A and B Let the time period of planet A be \( T_A \) and that of planet B be \( T_B \). According to the problem, we have: \[ T_B = 2\sqrt{2} \cdot T_A \] ### Step 3: Find the radius of planet B in terms of radius of planet A Using the relationship derived from Kepler's law, we can express the radius of planet B in terms of the radius of planet A: \[ r_B \propto T_B^{2/3} = (2\sqrt{2} \cdot T_A)^{2/3} \] Calculating this gives: \[ r_B \propto (2\sqrt{2})^{2/3} \cdot T_A^{2/3} \] Calculating \( (2\sqrt{2})^{2/3} \): \[ (2\sqrt{2})^{2/3} = (2^{1} \cdot 2^{1/2})^{2/3} = 2^{(1 + 1/2) \cdot (2/3)} = 2^{(3/2) \cdot (2/3)} = 2^{1} = 2 \] Thus, we have: \[ r_B = 2 \cdot r_A \] ### Step 4: Find the ratio of the solar constants The solar constant (intensity of sunlight) at a distance \( r \) from the sun is inversely proportional to the square of the distance from the sun: \[ I \propto \frac{1}{r^2} \] Thus, the ratio of the solar constants \( I_A \) and \( I_B \) for planets A and B can be expressed as: \[ \frac{I_A}{I_B} = \frac{r_B^2}{r_A^2} \] Substituting \( r_B = 2r_A \): \[ \frac{I_A}{I_B} = \frac{(2r_A)^2}{r_A^2} = \frac{4r_A^2}{r_A^2} = 4 \] ### Final Answer The ratio of the solar constant for planet A to that of planet B is: \[ \frac{I_A}{I_B} = 4 \]

To solve the problem, we will follow these steps: ### Step 1: Understand the relationship between time period and radius According to Kepler's third law of planetary motion, the square of the time period \( T \) of a planet is directly proportional to the cube of the radius \( r \) of its orbit around the sun. This can be expressed as: \[ T^2 \propto r^3 \] From this, we can derive the relationship: ...
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