- #1
lignocaine
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Hi everyone.
Im studying basic physics for my anaesthesia primary exams and came across the subject of work. I am however finding some difficulty grasping the concept of work done against gravity. The example given in my literature for work done against gravity is the following:
lifting an apple of 102grams 1m vertically will require 1joule of energy.
here it is explained that because the apple exerts a downward force of 1N (0.102kg x 9.8m/s) that an equally opposite force of 1N will need to be exerted upwards to move the object against gravity.
But, if 1N is exerted in an upward direction, the apple will remain still in your hand because the net forces acting on the apple are zero.
So in order to move the apple against gravity, a force of greater than 1N will have to be exerted by your hand.
An example would be using a force of 1.5N over a distance of 1m which would effectively yield a force of 0.5N acting upwards and if this example is used, the work done to move the apple would be 0.5N x 1m = 05J
If a higher upward acting force was used, then the resulting work done to move the object 1m would be even higher
So, the work done to move a fixed mass object 1m against gravity can vary depending on the net force acting on the object?
Is my logic flawed and if yes, where?
Im studying basic physics for my anaesthesia primary exams and came across the subject of work. I am however finding some difficulty grasping the concept of work done against gravity. The example given in my literature for work done against gravity is the following:
lifting an apple of 102grams 1m vertically will require 1joule of energy.
here it is explained that because the apple exerts a downward force of 1N (0.102kg x 9.8m/s) that an equally opposite force of 1N will need to be exerted upwards to move the object against gravity.
But, if 1N is exerted in an upward direction, the apple will remain still in your hand because the net forces acting on the apple are zero.
So in order to move the apple against gravity, a force of greater than 1N will have to be exerted by your hand.
An example would be using a force of 1.5N over a distance of 1m which would effectively yield a force of 0.5N acting upwards and if this example is used, the work done to move the apple would be 0.5N x 1m = 05J
If a higher upward acting force was used, then the resulting work done to move the object 1m would be even higher
So, the work done to move a fixed mass object 1m against gravity can vary depending on the net force acting on the object?
Is my logic flawed and if yes, where?