Solving Kinetic Energy: Mass, Velocity, and Jogger's Speed

AI Thread Summary
To solve for the mass of the continent, the volume is calculated as 4200 km on each side and 32 km deep, leading to a mass of approximately 3.58 x 10^14 kg using the given density of 2680 kg/m^3. The kinetic energy (KE) of the continent is then computed using the formula KE = 0.5 * m * V^2, resulting in a value of about 8.6 x 10^12 J. For the jogger, with a mass of 75 kg and the same kinetic energy as the continent, the velocity is determined to be approximately 6.78 m/s. The discussion emphasizes the importance of understanding the relationship between mass, velocity, and kinetic energy in solving these physics problems. Overall, the calculations illustrate the application of fundamental physics equations to real-world scenarios.
anglum
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kinetic energy?

a continent is 4200 km on a side and 32 km deep

its mass density is 2680 kg/m^3
it is moving at an avg speed of 4.8cm/year

what is its mass? answer in units of J

what is its kinetic energy? answer in units of J

a jogger with mass 75kg has the same kinetic energy as the continent... what is his velocity?? answer in units of m/s


i know the KE equation is KE = .5 * m * V^2

i am stuck on what my steps are with this problem... i know if i solve the first part the 2nd and 3rd parts will be easy becuz i plug them into the KE equation
 
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to find the mass of the contintent i would take

Density = mass/volume

2680kg/m^3 = mass / (42000000m * 4200000m * 32000m)

and then solve for mass and that gives me the mass in kg?
 
yes...exactly...then plug in for KE equation
 

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