A person exercising in the gym lifts a heavy load of mass 50kg through a distance of 0.75m in 0.5 seconds
(a) If the strength of gravity is 9.8 N/kg what is the lifting force in Newtons the person must use ?
(b) What is the work done in joules by the person in lifting the weight with this force?
(c) What is the power output of the person in joules per second ?
* explanations where needed would be so helpful as I want to understand when i need to do it for real
(a) If the strength of gravity is 9.8 N/kg what is the lifting force in Newtons the person must use ?
(b) What is the work done in joules by the person in lifting the weight with this force?
(c) What is the power output of the person in joules per second ?
* explanations where needed would be so helpful as I want to understand when i need to do it for real
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(a) By the formula: force = mass * acceleration ; F = 50 * 9.8 ; F = 490N
(b) By the formula: work done = force * distance ; E = 490 * 0.75 ; E = 367.5J
(c) By the formula: power = energy / time ; P = 367.5 / 0.5; P = 735W
The general trick to these questions is just to apply the formulas (and rearrange if necessary) with the information you are given.
(b) By the formula: work done = force * distance ; E = 490 * 0.75 ; E = 367.5J
(c) By the formula: power = energy / time ; P = 367.5 / 0.5; P = 735W
The general trick to these questions is just to apply the formulas (and rearrange if necessary) with the information you are given.