Determine the mechanical energy of this object: a 2-kg pendulum has a speed of 1 m/s at a height of 1/2 meter.

A: 1 J
B: 10.8 J
C: 2 J
D: 9.8 J

Respuesta :

the answer is B 10.8 j 

Answer:

The mechanical energy of this object is 10.8 Joules.

Explanation:

Mechanical energy is the sum of kinetic energy and potential energy.

[tex]M.E=P.E+K.E[/tex]

[tex]M.E=mgh+\frac{1}{2}mv^2[/tex]

m = mass of the object

v = velocity of the moving object

h = height at which an object is placed

g = Acceleration due to gravity

We have : m = 2 kg. v = 1 m/s , h = 1/2 m

[tex]M.E=2 kg\times 9.8 m/s^2\times \frac{1}{2}m+\frac{1}{2}\times 2 kg \times (1 m/s)^2[/tex]

[tex]M.E=9.8 J+1 J=10.8 J[/tex]

The mechanical energy of this object is 10.8 Joules.