contestada

A 6.0-kg object, initially at rest in free space, "explodes" into three segments of equal mass. Two of these segments are observed to be moving with equal speeds of 20 m/s with an angle of 60° between their directions of motion. How much kinetic energy is released in this explosion?

Respuesta :

Answer:

[tex]Q = 2000 J[/tex]

Explanation:

As we know that the 6 kg object was at rest initially

So here since net force on the system is zero

so the momentum of the system will always remains conserved

so we can say

[tex]0 = P_1 + P_2 + P_3[/tex]

now we know that

[tex]P_1 = P_2 = P[/tex]

and the angle between the two objects is 60 degree

so we can say

[tex]\vec P_1 + \vec P_2 = \sqrt{P_1^2 + P_2^2 + 2P_1 P_2cos60}[/tex]

[tex]\vec P_1 + \vec P_2 = \sqrt{P^2 + P^2 + 2P^2(0.5)} = \sqrt3 P[/tex]

now we can say that the speed of the third mass will be

[tex]v_3 = \sqrt 3 (20) m/s[/tex]

now the total kinetic energy released in this system is given as

[tex]Q = \frac{1}{2}mv_1^2 + \frac{1}{2}mv_2^2 + \frac{1}{2}mv_3^2[/tex]

[tex]Q = \frac{1}{2}(2)(20^2) + \frac{1}{2}(2)(20^2) + \frac{1}{2}(2)(20\sqrt3)^2[/tex]

[tex]Q = 2000 J[/tex]