The answer is B, Law of Kinetic Energy
A and c...............................
Mechanical waves travel the fastest in
solids and liquids because the
molecules are more closely packed together than gases, so energy is transferred
from one particle to another particle faster<span>.</span>
Refer to the diagram shown below.
The given data is
mass, kg Coordinates. m
------------- -----------------
2 (0, 0)
2 (2, 0)
4 (2, 1)
Total mass, M = 2+2+4 = 8kg
Let (x,y) be the coordinates of M.
Then, taking moments about the origin, we obtain
8x = 2*0 + 2*2 + 4*2 = 12
x = 1.5 m
8y = 2*0 + 2*0 + 4*1 = 4
y = 0.5 m
Answer: (1.5, 0.5) m