Question

Review Conceptual Example 7 before starting this problem. A uniform plank of length 5.0 m and weight 225 N rests horizontally on two supports, with 1.1 m of the plank hanging over the right support (see the drawing). To what distance x can a person who weighs 385 N walk on the overhanging part of the plank before it just begins to tip?

Answer 1

0.82 m

Step-by-step explanation:

We are given that

Weight,
`w_1`=225 N

Length,l=5 m

d=1.1 m

We have to find the distance x for which person weighs 385 N walk on the overhanging part of the plank before it just begins to tip.

Half length=
`(l)/(2)=(5)/(2)=2.5 m`

`r=(l)/(2)-d=2.5-1.1=1.4 m`

`w_2=385 N`

When system in equilibrium then

`w_1r=w_2 x`

`225* 1.4=385* x`

`x=(225* 1.4)/(385)`

`x=0.82 m`