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प्रश्न
The weight of a person on planet A is about half that on the earth. He can jump up to 0.4 m in height on the surface of the earth. How high he can jump on planet A?
उत्तर
The weight of a person on a planet is half that on the earth,
WA = `1/2 "W"_"E"`
or mgA = `1/2 "mg_E"`
or `"g"_A = 1/2 "g"_E`
Now, as the person jumps, gain in potential energy remains the same.
So, mgAhA = mgE hE
∴ `"h"_A = ("g"_"E""h"_"E")/"g"_"A"`
= `("g"_"E" xx 0.4"m")/("g"_E/2)` (Using (I) nd hE = 0.4 m)
= 0.8m
(Using (i) and hE = 0.4 m)
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