Question

A 0.5 kg ball falls from a building that is 50 meters high. How much kinetic energy will it

Answer 1

Answer:

First you have to calculate the velocity it will be traveling at when it has fallen halfway, which is 5m in this problem. The kinematic equation V^2=v^2+2gd, where V is the velocity after falling through a certain distance under gravity, v is the initial velocity which is zero here, g is the gravitational acceleration(9.81ms^-2), and d is the distance through which it fell which is 5m here. Once you find the velocity V after falling through the 5m vertical distance or height under gravity, then you use the Kinetic energy equation K.E.=1/2MV^2(Where M is the mass which is 16kg here, and 9.90m/s is the calculated velocity V here) to calculate the instantaneous kinetic energy that the stone will be traveling with at that point. The calculated K.E. works out to be 784.8J(joules). The other way to do it is from energy principles. At the maximum height the potential energy would have been: PE=F•h=mgh=16kg•9.81m/s^2•10m=1,569.6J, hence at half the height the kinetic energy or KE would be half of that value which is 784.8 J, the same as in the earlier calculation. The solution through the energy-method is simpler and faster. Kaiser T, MD.

Answer 2

Answer:

thank you thank you thank you