A firecracker in a coconut blows the coconut into three pieces. Twopieces of equal mass fly off south and west, perpendicular to eachother, at 18 m/s. The third piece has twice the mass asthe other two.Part 1What is the speed of the third piece? (Answer in 2 sig figs andm/s)Part 2What is the direction of the third piece? (Answer in 2 sig figs anddegrees north of east)

Respuesta :

Answer:

1. 13 m/s

2. [tex]45^{\circ}[/tex] north of east

Solution:

As per the question:

Velocity of the two pieces with equal masses, 'm', v = 18 m/s

Mass of the third particle, M = 2m

Now,

To calculate the speed of the third piece

We know that:

Mass 1 flies off to South and mass 2 to West

Now, by the conservation of momentum in the x and y direction:

[tex]Mv'_{y} = mv[/tex]

[tex]2mv'_{y} = 18m[/tex]

[tex]v'_{y} = 9\ m/s[/tex]

Similarly,

[tex]Mv'_{x} = 18m[/tex]

[tex]v'_{x} = 9\ m/s[/tex]

The resultant velocity of the third piece:

[tex]v' = \sqrt{v'_{x}^{2} + v'_{y}^{2}} = \sqrt{9^{2} + 9^{2}} = 12.73\ m/s[/tex] ≈ 13 m/s

Now,

The direction of the third piece can be calculated as:

[tex]tan\theta = \frac{v'_{y}}{v'_{x}}[/tex]

[tex]\theta = tan^{- 1}(\frac{9}{9}) = 45^{\circ}[/tex] in the north of east direction.