a ladder of length 1.9 meters leans against the wall.
top end of falls at the rate of 0.345 m/s. how fast is bottom end moving when it is 0.5 m from the wall?
2006-09-27 17:32:14 · 3 answers · asked by ? 3 in Education & Reference ➔ Homework Help
l=lenghth of the ladder
x=distance between bottom end and wall
y=distance between top end and ground
so x^2+y^2=l^2
x^2+y^2=1.9^2
x=.5m
==>.5^2+y^2=1.9^2
==>y=1.833
now we differentiate with respect of time
d (x^2+y^2=1.9^2) /dt
==>2x*dx/dt+2y*dy/dt=0
x=.5
y=1.833
dy/dt=-.345
dx/dt=?
==>2*.5*dx/dt+2*1.833*-.345=0
==>1.265m/s
bottom end speed is 1.265m/s going away from wall.
I know my English is awful but wish it help you.
sorry for my English.
If you correct my writng errors in this solution and mail me or some how aware me of soloution I'll appreciate that.
thanks.
2006-09-28 01:12:20 · answer #1 · answered by Mamad 3 · 0⤊ 0⤋
I think there is some information you are not giving us in this problem. If it is leaning against a wall, how does it fall? Does the wall collapse? At what angle is it leaning? Is the bottom end doing much more than rotating while the top end is falling?
2006-09-28 00:56:50 · answer #2 · answered by Robert B 5 · 0⤊ 0⤋
dont read this cuz ur wasting ur time , i dont know ask ur teacher
2006-09-28 00:34:56 · answer #3 · answered by .................. 4 · 0⤊ 0⤋