Question

A frictionless pendulum is made with a bob of mass 19.7 kg. The bob is held at height = 0.934 meter above the bottom of its trajectory, and then pushed forward with an initial speed of 2.93 m/s. What amount of mechanical energy does the bob have when it reaches the bottom?
Elena
According to the law of conservation of energy in frictionless case the total mechanical energy of the pendulum is constant
E = mgh +mv²/2 = 19.7•9.8•0.934 + 19.7•2.93²/2 = …
anonymous
therefore the answer is 265 J