How to Calculate Energy to Push an Object 100 km Without Knowing Its Mass?

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Calculating the energy required to push an object 100 km into the air from Earth is feasible even without knowing its mass. The initial velocity needed is 1400 m/s, and while the equations for kinetic energy (E = 1/2 * m * v^2) and gravitational potential energy (E = mgh) both involve mass, they can be rearranged to estimate energy based on assumed mass values. Without a specific mass, exact energy calculations are impossible, but estimations can be made using average weights of similar objects. Ultimately, while precise calculations are limited by the unknown mass, approximations can provide useful insights.
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Is it possible to figure how much energy it takes to push an object with a unknown mass 100 km in the air from earth? I was able to figure the inital velcity required to do so which is 1400 m/s. Any ideas?
 
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You'd need the mass...Both in the expression of KE & gravitational potential energy (or work done by gravity forces) the mass of the moving body appears...

Daniel.
 


It is certainly possible to calculate the amount of energy required to push an object 100 km in the air from Earth, even without knowing the mass of the object. This can be done using the equation E = 1/2 * m * v^2, where E is the energy, m is the mass, and v is the velocity.

In this case, since we know the initial velocity required (1400 m/s), we can rearrange the equation to solve for mass: m = 2 * E / v^2. However, without knowing the mass, we cannot determine the exact amount of energy needed. We would need to make an assumption about the mass in order to calculate the energy required.

Alternatively, we could also use the equation E = mgh, where m is the mass, g is the gravitational acceleration (9.8 m/s^2), and h is the height (100 km). Again, without knowing the mass, we cannot calculate the exact energy required. However, we could estimate the mass based on the average weight of similar objects and use that to determine the energy needed.

In conclusion, while it may be challenging to calculate the exact amount of energy needed without knowing the mass, it is still possible to make an estimation or approximation using equations and assumptions.
 
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