Question

a body of mass 1.5 kg thrown vertically upward with the initial velocity 30 metre per second what is potential energy at the end of 3 second

Answer 1

s=ut-1/2g*t∧2
  =30*3-1/2*10*3*3
  =45m
PE=mgh
    =1.5*10*45
    =675J

Answer 2

Hey friend, Harish here.

Here is your answer.
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Given that ,

 $u = 30 m/s$

$mass =1.5 kg.$
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To find,

The potential energy after 3 sec.
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Solution,

$h = ut-\frac{1}{2}gt^{2}$

⇒$h = (30)(3) - \frac{1}{2}(10)( 3)^{2}$

⇒$h = 90 - 45$

⇒$h = 45m$
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Now, We know that ,

$PE = mgh$

⇒$PE = 1.5 (10) (45)$

⇒[tex]PE = 15 (45) [/tex]

⇒$PE = 675 J$
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Hope my answer is helpful to u.