Respuesta :
Answer: The correct answer is A) Use an inclined plane of 8 m
Work :
Work is defined as force applied to an object to move it to some distance . It is calculated as product of force and displacement .
W = F* d
Where : W =work (N-m) F = force (N) d = displacement (m)
When a body is lifted , work can be expressed as :
W = m*g*h ( h = height )
Also force due to gravitation can be given as
F = m* g
where :
g = gravitational acceleration ([tex] 9.8 \frac{m}{s^2} [/tex]
Hence Work can be written as : W = F * h
Given :
Force on load due to gravitation = 100 N Height = 2 m
Force applied = 25 N displacement = ?
Work done to lift the load to 2 m = F * h
= 100 N * 2 m = 200 N-m
Plugging W = 200 N-m in work formula
W = F* d
200 N-m = 25 N * d
Dividing both side by 25 N
[tex] \frac{200N-m}{25 N} = \frac{25 N * d}{25 N} [/tex]
d = 8 m
Hence, to lift the load using 25 N , the inclined plane of 8 m can be used .