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Good day.
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The topic is about newton's second law of motion.
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It states that force or the net force on the object is equal to the product of mass and acceleration.
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Suppose we have a ball which is applied with an upward force of 82 newton and with this much of force, f a applied or f a is applied force, the ball accelerates at a rate of a.
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But if we increase the applied force to 92 newtons the acceleration is found to increase by two times or twice of the original acceleration what we wish to find here is first the weight of the ball and second the value of the acceleration a so let us first consider the free body diagram of the ball so the ball is the ball is is acted by the force applied f .a.
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Going upward and the force by the gravity, which is the ball's weight.
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So that the net force in this case will be, is the vector sum, which is, by the way, the vector sum of the forces acting on the object.
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And since the two forces here act in opposite direction, then the vector sum will be their difference, like f .a.
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Minus w.
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And this is equal to, according to new to second law, ma.
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So we can solve for a here as f -a minus w over m.
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Now we note that m or rather w is equal to mass times the acceleration due to gravity.
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So rearranging to solve for m gives w over g...