Gravity Physics
A spherical non rotating planet has a radius R and a uniform density throughout its volume. Suppose a narrow tunnel were drilled through the planet along one of its diameters as shown in the figure below, in which a small ball of mass m could move freely under the influence of gravity. Let r be the distance of the ball from the center of the planet. Suppose the ball is dropped into the tunnel from rest at the planet's surface.
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F. Write an equation that could be used to calculate the time it takes the ball to move from point P to the center of the planet.
SOLUTION MISSING: Unfortunately the author of this youtube video removed their content. You may be able to find a similar problem by checking the other problems in this subject. If you want to contribute, leave a comment with the link to your solution.Related Problems
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B. Determine the height of the track at point x. It is known that the roller coaster has a velocity of 30 m/s at x.
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B. Assume the block is released at height h = 6.0 R, what are the magnitude and direction of the horizontal force competent acting on the block at point Q?