Question

A ladder 25 m long is learning against the wall which is perpendicular to the level ground The bottom of the ladder is 7 m from the base of the wall If the top of the ladder slips down 4m how much will the bottom of the ladder slip ?

• A. 7 m
• B. 8 m
• C. 10 m
• D. 4 m

Answer 1

The correct option is B 8 m

Given the length of ladder is 25 m and the and bottom of ladder is 7 m from the base

Then height of ladder from bottom h=$\sqrt{(25{)}^2-(7{)}^2}=\sqrt{625-49}=\sqrt{576}=24$ m

If the ladder slip down 4 m then height =24-4=20m

Then ladder on ground from bottom =$\sqrt{(25{)}^2-(20{)}^2}=\sqrt{625-400}=\sqrt{225}=15$ m

So ladder slip in bottom =15-7=8 m