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I just need to know the equations for both of these-From what height would a compact car have to be dropped to have the same kinetic energy that it was when being driven at 30 m/s?-B) write an equation and answer what height the car would have to be dropped from.

1 Answer

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Given data

*The given speed of the compact car is v = 30 m/s

*The value of the acceleration due to gravity is g = 9.8 m/s^2

The expression for the height of the car is given by the conservation of energy as


\begin{gathered} U_p=U_k \\ mgh=(1)/(2)mv^2 \\ h=(v^2)/(2g) \end{gathered}

Substitute the known values in the above expression as


\begin{gathered} h=((30)^2)/(2*9.8) \\ =45.91\text{ m} \end{gathered}

Hence, the height of the car would have to be dropped them is h = 45.91 m

User Andy Long
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