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Help please i have a 17 as a grade :)

Help please i have a 17 as a grade :)-example-1
User Tocco
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1 Answer

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22 votes

Given

A 50kg boy

A 100 kg father

Speed (both) 5 m/s

Procedure

Kinetic energy is a form of energy that an object or a particle has by reason of its motion

For the boy


\begin{gathered} K_b=(1)/(2)mv^2 \\ K_b=(1)/(2)\cdot50\operatorname{kg}\cdot(5m/s)^2 \\ K_b=625J \end{gathered}

For the father


\begin{gathered} K_f=(1)/(2)mv^2 \\ K_f=(1)/(2)\cdot100\operatorname{kg}\cdot(5m/s)^2 \\ K_f=1250J \end{gathered}

Now, let's compare the kinetic energy between father and boy


\begin{gathered} \frac{father^(\prime)s\text{ KE}}{boy^(\prime)s\text{ KE}} \\ (1250J)/(625J) \\ \frac{father^(\prime)s\text{ KE}}{boy^(\prime)s\text{ KE}}=2 \end{gathered}

The father's KE is twice the boy's kinetic energy

Screenshot:

Part 2:

Part 1:

Help please i have a 17 as a grade :)-example-1
Help please i have a 17 as a grade :)-example-2
User Duffp
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