How much force needed to partialy lift object?

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To calculate the force needed to partially lift an object with evenly distributed weight, the formula involves applying half the total weight at one end while the other end remains grounded. For a uniform object, such as a metal rod, the force required can be derived from the moments of force around the support point. Specifically, the equation mg x L/2 = F x L applies, where m is mass, g is gravitational acceleration, and L is the length of the object. This means that knowing the mass, length, height, and standard gravity allows for precise calculation of the necessary lifting force. Understanding these principles is crucial for applications like push-ups or similar movements.
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Hi,

Imagine you have an object where the weight is equally divided. What would be the formula to calculate the force needed to lift the object up to a distance without lifting it up completely. For example, a push-up, your feet keep touching the ground but you push your self up. How would one calculate that? If the mass, length, height and standard gravity are known?

Thanks in advance
 
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Welcome to the Forum.
If the weight is uniformly distributed along the length of the mass, like a metal rod, for example; then the force you would need to apply to the one end, the other staying on the ground, would be exactly half the weight.
Proof using moments of force about the support point on the ground gives mg x L/2 = F x L where L is the length of the rod.
Diagram can be provided if you want one!
 
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