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QNEET-2024-Ph-75: NEET 2024 Physics - Class 11 NEET-2024-Ph-75 Solution: The mass of a planet is \( {1}{10}\)th that of the earth and…
The mass of a planet is th that of the earth and its diameter is half that of the earth. The acceleration due to gravity on that planet is:
Multiple Choice Options
- A 19.6 m s _ 2
- B 9.8 m s _ 2
- C 4.9 m s _ 2
- D 3.92 m s _ 2
Step-by-Step Verified Solution
The acceleration due to gravity (g) on a planet is given by the formula:
g = G M R 2
where:
G G is the universal gravitational constant,
M M is the mass of the planet, and
R R is the radius of the planet.
In this question, we know that:
The mass of the planet M p M p _ is 1 10 10 1 _ of the mass of the earth M e M e _ , so M p = M e 10 M p _ = 10 M e _ _ .
The diameter of the planet is half that of earth. Since the diameter is twice the radius, a diameter half that of earth implies the radius R p R p _ is also half the radius of the earth R e R e _ . Therefore, R p = R e 2 R p _ = 2 R e _ _ .
Using the formula for acceleration due to gravity and substituting the above information:
g p = G M p R p 2 = G M e 10 ( R e 2 ) 2
Simplify the expression:
g p = G M e 10 _ 4 R e 2 = 4 10 G M e R e 2
Knowing that G M e R e 2 G R e 2 _ M e _ _ is the acceleration due to gravity on Earth g e � 9.8 m / s 2 g e _ � 9.8 m/s 2 , we substitute this value into the equation:
g p = 4 10 _ 9.8 m / s 2 = 3.92 m / s 2
Thus, the acceleration due to gravity on the planet is 3.92 m / s 2 3.92 m/s 2 , which corresponds to:
Option D: 3.92 m / s 2