contestada

You're heading an international effort to save Earth from an asteroid heading toward us at 13 km/s . Your team mounts a rocket on the asteroid and fires it for 10 min, after which the asteroid is moving at 23 km/s at 26 ∘ to its original path.

In a news conference, what do you report for the acceleration imparted to the asteroid?

Express your answers using two significant figures separated by a comma. Assume that the positive x axis is in the direction of the initial motion of asteroid and y axis is perpendicular to it.

ax=?

ay=?

Respuesta :

Answer:

[tex]a_x=12.8m/s^{2}[/tex]

[tex]a_y=16.8m/s^{2}[/tex]

Explanation:

To solve this problem, we need to make use of Newton's Second Law of motion which states that the rate of change of momentum of an object is directly proportional to the force applied to the body. Mathematically, this is

[tex]F=\frac{\Delta P}{\Delta t}[/tex],

where [tex]F[/tex] is the force applied to the object, [tex]\Delta P[/tex] is the change in momentum and, [tex]\Delta t[/tex] is the time it takes for the momentum to change.

We can simplify this equation remembering that

[tex]F=ma\\\Delta P= P_{f}-P_{i}=mv_{f}-mv_{i}=m(v_{f}-v_{i})[/tex]

where [tex]m[/tex] is the mass, [tex]a[/tex] is the acceleration, [tex]v[/tex] is the velocity and, [tex]i[/tex] and [tex]f[/tex] stands for initial and final, respectively.

Now, Newton's Second Law becomes

[tex]ma=\frac{m(v_f-v_i)}{\Delta t}\\\\\\a=\frac{(v_f-v_i)}{\Delta t}[/tex].

Listing the data we have:

1. [tex]v_{i}=13km/s=13000m/s[/tex]

2.[tex]v_f=23km/s=23000m/s[/tex] at [tex]26^{\circ}[/tex]

3. [tex]\Delta t=10min=600s[/tex].

Considering x-axis:

[tex]a_x=\frac{(v_f_x-v_i_x)}{\Delta t}[/tex]

At the begining, the motion was along the x-axis, and at the end, the asteroid was moving at

[tex]v_f_x=v_f*cos(\theta)=23000cos(26)=20672.26m/s[/tex],

so

[tex]a_x=\frac{(20672.26-13000)}{600}\\\\a_x=12.8m/s^{2}[/tex]

Now, considering y_axis

[tex]a_y=\frac{(v_f_y-v_i_y)}{\Delta t}[/tex].

At the begining, there was no initial velocity, this means [tex]v_i_y=0[/tex]. At the end, the velocity was [tex]v_f_y=v_fsin(\theta)=26000sin(26)=10082.54m/s[/tex], so

[tex]a_y=\frac{(10082.54)}{600}[/tex]

[tex]a_y=16.8m/s^{2}[/tex]