Question

A vase with a mass of 0.800 kilograms falls from a height of 0.750 meters to a position of 0.500 meters above the floor. Ignoring frictional effects, the total mechanical energy at the 0.500 position is _____. 0.00 J less than 5.88 J more than 5.88 J exactly 5.88 J

Answer 1

total mechanical energy = Ек + Ep
Ek = (m·V²)/2
Ep = m·g·h

S = (V² + Vo²)/(2·g)

g = 9,8
m = 0,8 kg
Vo = 0
h = 0,5 m
S = 0,75 - 0,5 = 0,25 m

S = V²/(2·g)
V² /2 = g·S
Ek = (m·V²)/2 = m·g·S
Ek = 0,8·9,8·0,25 = 1,96 J

Ep = 0,8·9,8·0.5 = 3,92 J

E = 1,96 + 3,92 = 5,88 J

Answer 2

Answer:

exactly 5.88 J

Explanation:

Let's calculate the initial total mechanical energy of the vase when it starts its fall, from a height of 0.750 m. At that moment, the vase does not have kinetic energy, but only potential energy. So, its total mechanical energy is given by:

$E=mgh=(0.800 kg)(9.8 m/s^2)(0.750 m)=5.88 J$

When the vase falls and reach the position at 0.500 m, part of this energy has been converted into kinetic energy, However, the total mechanical energy is constant, because there are no frictional effects: therefore, the total mechanical energy at 0.500 m above the floor is still equal to the initial total mechanical energy, 5.88 J.