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A 25 kg mass is thrown from the ground to a height of 50 m. (a) find the kineticenergy of the mass at this height.; (b) find the potential energy of the mass at thisheight. ; (C) find the velocity of the mass when it reach the ground.

User Ricardoorellana
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1 Answer

17 votes
17 votes

Given

m: mass

m = 25 kg

h: height

h = 50 m

Procedure

(a) Kinetic energy is directly proportional to the mass of the object and to the square of its velocity. At this height initial velocity is equal to zero

K = 0 J

(b) The potential energy of any given object is a measurement of its potential to do work, create heat and generate power.


\begin{gathered} U=mgh \\ U=25\operatorname{kg}\cdot9.8m/s^2\cdot50m \\ U=12250\text{ J} \end{gathered}

(c) When the mass reaches the ground all the potential energy is transformed into kinetic energy.


\begin{gathered} (1)/(2)mv^2=U \\ (1)/(2)mv^2=12250J \\ v=\sqrt[]{\frac{2\cdot12250}{25\operatorname{kg}}} \\ v=31.30\text{ m/s} \end{gathered}

User Zontragon
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