Question

A 50 kg box hangs from a rope. What is the tension in the rope if: The box is at rest? The box moves up at a steady 5.0 m/s? The box has vy=5.0 m/s and is speeding up at 5.0 m/s2? The box has vy=5.0 m/s and is slowing down at 5.0 m/s2?

Answer 1

Answer:

(a) $T_{1}=490N$

(b) $T_{2}=240N$

Explanation:

For Part (a)

Given data

The box moves up at steady 5.0 m/s

The mas of box is 50 kg

As ∑Fy=T₁ - mg=0

$T_{1}=mg\\T_{1}=(50kg)(9.8m/s^{2} ) \\T_{1}=490N$

For Part(b)

Given data

$v_{iy}=5m/s\\ a_{y}=-5.0m/s^{2}$

As ∑Fy=T₂ - mg=ma

$T_{2}=mg+ma_{y}\\T_{2}=m(g+ a_{y})\\T_{2}=50kg(9.8-5.0) \\T_{2}=240N$