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How much work done in pulling up a block...

How much work done in pulling up a block of wood weighing 2kN for length of 10 m on smooth incline plane at angle `15^(@)` with horizontal ?

A

`9.82`J

B

89 J

C

`4.35` kJ

D

`5.17` kJ

Text Solution

Verified by Experts

The correct Answer is:
D
Force applied for displacing body on smooth incline plane
`F = ma = mg sin alpha = W sin alpha `
Now `sin alpha =sin 15^(@) xx 0.2588`
` F = 0.5176 xx10^(3)N`
` :. "Work W" =F.d `
`= 0.5176 xx10^(3) xx10`
` =5.17 xx10^(3) xx10`
` = 5.17 xx10^(3)J = 5.17 kJ `
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