Question

the kinetic energy of a body is 250 find work done to move a body of mass 20 kg up to a height of 5 metres​

Answer 1

Answer:

$w = fs \\ \\ w = mg \: \times s \\ \\ w = 20 \times 10 \times 5 = 1000 \: joules \\ \\ \\ ke = 750 \: \: joules \\ \\ \\ energy \: \: needed = w - ke \\ \\ energy \: = 1000 - \: 250 = 750joules$

Answer 2

Answer:

\begin{gathered}w = fs \\ \\ w = mg \: \times s \\ \\ w = 20 \times 10 \times 5 = 1000 \: joules \\ \\ \\ ke = 750 \: \: joules \\ \\ \\ energy \: \: needed = w - ke \\ \\ energy \: = 1000 - \: 250 = 750joules \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \\ \end{gathered}

w=fs

w=mg×s

w=20×10×5=1000joules

ke=750joules

energyneeded=w−ke

energy=1000−250=750joules