Question

An elevator and its load have a combined mass of 1450 kg. Find the tension in the supporting cable when the cab, originally moving downward at 11 m/s, is brought to rest with constant acceleration in a distance of 41 m.

Answer 1

16.4 kN

Step-by-step explanation:

m = 1450 kg, v = 11 m/s, d = 41 m

moving down, decelerate, so acceleration is up

a = v²/(2d) = 11²/(2*41) = 1.48 m/s²

tension = T

T - mg = ma

so

T = m(g + 1) = 1450(9.81 + 1.48) = 16,371 N = 16.4 kN