According to my examination I have confirmed that I do NOT repeat do NOT know this.
F~1/r²
doubling the distance r, Decreases the force by ¼
Answer:
The environmental problems directly related to energy production and Electricity is a secondary energy source that is generated producedfrom primary energy sources:
hope that helps im new so have a good day (:
Missing question: "how much work is done by the teacher?" (found on internet)
Solution:
The work done to move the desk across the floor is equal to

where F is the horizontal force applied to move the desk, and d is the distance covered by the desk. If we use F=20 N and d=5 m, we find the work done:
The average weight of an athlete should be around 60kg so from the information that the athlete can run 100m in 10s, we can calculate that their average speed is 10m/s. Using the kinetic energy formula, Ek = 1/2mv^2 we can calculate the kinetic energy using 60kg as the mass.
(1/2)(60)(10^2) = Ek
Ek= 3000J