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A horse is tied to a post by a rope. If ...

A horse is tied to a post by a rope. If the horse moves along a circular path always keeping the rope tight, and describes `88` metres when it traces `72^@` at the centre, find the length of the rope.

Text Solution

Verified by Experts

The correct Answer is:
70 m

Let the post be at point P and PA be the length of the rope in tight position. Suppose the horse moves along the are AB so that `angle APB=72^@" and are "AB=88m`
Let r be the length of the rope, i.e., PA = r meters.
Now, `theta=72^@=(72xxpi/182)^R`
`=((2pi)/5)^R`
and `s=88m`
`:. theta=("Are")/("Radius")`
`or (2pi)/5=88/r`
`or r=88xx5/(2pi)=70m`
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