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Question
A solid sphere of mass 1 kg rolls on a table with linear speed 2 m/s, find its total kinetic energy.
Solution
Solution:
Given: m = 1kg, v = 2 m/s
To find: Total K.E
`E=1/2mv^2[1+k^2/R^2]`
for a solid sphere, `k^2=(2/5)R^2`
`therefore E=1/2 mv^2[1+(2/5R^2)/R^2]`
`therefore E=1/2xx7/5xxmv^2`
`therefore E=1/2xx7/5xx1xx2^2`
`therefore E=14/5`
`therefore E=2.8J`
The total kinetic energy of the solid sphere is `2.8J`
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