Hallar la fuerza se debe aplicar a una palanca de primer género para levantar un peso de 456 kp, cuyos brazos de fuerza y resistencia son: 180 y 36 cm respectivamente:
ALTERNATIVAS:
A) 14,21 kp
B) 229 kp
C) 91,2 kp
D) 76 kp
E) 85 kp

F = 91.2 kp

the correct answer is C

Explanation:

On a first degree lever, the fulcrum (pivot point) is between the weight to be lifted and the force applied. Knowing what force we must apply, write the endowment equilibrium equation.

We will assume that the counterclockwise direction of rotation is positive

             W d₁ - F d₂ = 0

              F = W d₁/ d₂

where

they indicate the value of the weight to lift W = 456 kp and its distance from the fulcrum d₁ = 36 cm; the distance to the applied force (F) is d₂ = 180 cm

let's calculate

            F = 456 36/180

            F = 91.2 kp

therefore the correct answer is C

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