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3 years ago

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A new planet is discovered that has twice the Earth's mass and twice the Earth's radius. On the surface of this new planet a per

son who weights 500 N on Earth would experience a gravitational force of ______.
(A) 125 N
(B) 250 N
(C) 500 N
(D)) 1000 N
(E) 2000 N

1 answer:

Margarita [4]3 years ago

8 0

Answer:

option B

Explanation:

Radius of new planet,R' = 2R

Mass of the earth, M' = 2 M

R and M is the Radius and Mass of the earth.

Weight of the person on earth = 500 N

Weight of the person in the new planet = ?

We know acceleration due to gravity is calculated by using formula

$g = \dfrac{GM}{R^2}$

now, acceleration due to gravity on the new planet

$g' = \dfrac{GM'}{R'^2}$

$g' = \dfrac{G(2M)}{(2R)^2}$

$g' =\dfrac{1}{2} \dfrac{GM}{R^2}$

$g' =\dfrac{g}{2}$

here acceleration due to gravity is half in new planet, so weight will also be half on the new planet.

Weight on the new plane is equal to $\dfrac{500}{2}$ = 250 N

correct answer is option B

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3 0

3 years ago