Question

A plank 4.7 m long and weighing 118 N has its left end resting on a block and the other end supported by a rope. The plank is in the horizontal position. If the greatest tension the rope can withstand is 435 N, how far from the block can a 51.0 kg girl walk out on the plank before the rope breaks?

Answer 1

Distance walked by the girl before the rope breaks is : 3.53 m

Given data

Length of plank = 4.7 m

Mass of plank = 118 N

Greatest tension the rope can withstand = 435 N

mass of girl = 51.0 kg

Determine distance walked by the girl before the rope breaks

First step : balance the torque to determine the distance x

mg * x + 118 * 2.35  = 435 * 4.7 ----- ( 1 )

where ; x = distance of the girl from point A , Also 118 N willact on the center of mass of the plank hence ( length of plank / 2 = 2.35 m )

Back to equation ( 1 )

( 51 * 9.81 ) x = 2044.5 - 277.3

therefore : x = 3.53 m

Hence we can conclude that Distance walked by the girl before the rope breaks is : 3.53 m

Learn more about Tension on rope : https://brainly.com/question/24994188