What is the gravitational potential energy of the obectj

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To find the gravitational potential energy of a 0.7 kg object thrown vertically at 29 m/s, calculate the energy at its highest point using the formula E = 1/2mv^2, considering the initial potential energy as zero. For the 8.9 kg object initially moving at 21 m/s and gaining 1.6 J of energy, the final speed can be determined by accounting for the energy reduction in dynamic energy, applying the equation deltaE = 1/2m(deltav)^2. The final speed is obtained by subtracting the speed reduction from the initial speed. These calculations illustrate the principles of energy conservation and transformation in physics. Understanding these concepts is crucial for solving similar problems.
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hi, please help me figure these problems out. much appreciated.

1. an object of mass .7kg is thrown vertically upwards at a speed of 29 m/s. What is the gravitational potential energy of the obect at the highest point of its trajectory?

2. an object of mass 8.9kg moves with initial speed 21 m/s then interacts with its environment, gaining 1.6J of energy. What is the speed of the object after after the interaction is completed?
 
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1. You have to consider the gravitational potential at the start point as zero. Then the potential at the highest point equals to the dynamic energy of the object or:

E = 1/2mv^2.

2. After the interaction, the dynamic energy is reduced by 1.6J. You can calculate the speed reduction via equ. deltaE=1/2m(deltav)^2. Then the final speed is known by a subtraction
 
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