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solaris123
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I concluded that ((mv^2)/r)-(mg) was equal to the normal force but the answer says its equal to ((mv^2)/r)-(2mg). Could someone explain why to me please?
"A half sphere of radius r is fixed to a horizontal floor. The inner surface is smooth. A small ball of mass m is at the bottom of the sphere and is given a velocity v. The initial velocity v is sufficiently large so that the small ball reaches point Q at the height r. Find the magnitude of the normal force exerted by the sphere on the ball when the ball passes through point Q. The acceleration due to gravity is equal to g."
Possible answers
(a) (mv^2)/r: not the answer because it doesn't account for gravity
(b) ((mv^2)/r)-(mg): my answer because it accounts for gravity
(c) ((mv^2)/r)-(2mg): the right answer but no clue why
(d)-(h): Other answers which use the kinetic energy formula and thus are not relevant
"A half sphere of radius r is fixed to a horizontal floor. The inner surface is smooth. A small ball of mass m is at the bottom of the sphere and is given a velocity v. The initial velocity v is sufficiently large so that the small ball reaches point Q at the height r. Find the magnitude of the normal force exerted by the sphere on the ball when the ball passes through point Q. The acceleration due to gravity is equal to g."
Possible answers
(a) (mv^2)/r: not the answer because it doesn't account for gravity
(b) ((mv^2)/r)-(mg): my answer because it accounts for gravity
(c) ((mv^2)/r)-(2mg): the right answer but no clue why
(d)-(h): Other answers which use the kinetic energy formula and thus are not relevant
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