Question

a 20 - kg barrel is rolled up a 20 - m ramp to the back of a truck whose floor is 5.0 m above the ground. what work is done in loading one barrel into the truck?
4900 j
980 j
impossible to tell because velocity not given
19,600 j

Explanation:

Step1: Calcular la fuerza gravitacional

La fuerza gravitacional \(F = mg\), donde \(m = 20\space kg\) y \(g= 9.8\space m/s^{2}\). Entonces \(F=20\times9.8 = 196\space N\).

Step2: Calcular el trabajo

El trabajo \(W = F\times h\), donde \(h = 5.0\space m\). Entonces \(W=196\times5=980\space J\).

Answer:

980 J