Respuesta :
Answer:
8.66 m/s and 7.75 m/s
Explanation:
from the question we were given
mass of A = 1900 kg
mass of B = 1500 kg
velocity of B = 17 m/s
direction of A and B after collision = 60 degrees south of east.
and we can get the momentum from the parameters above
momentum = mass x velocity
momentum of car B = 1900 x 17 = 25,500 kgm/s
NOTE: the first diagram shows the cars and the direction they move at, while the second diagram shows the cars and their directions arranged to form a triangle.
The momentum of the cars is the parameter that would be used in calculations for the triangle.
- from the second diagram, to find the momentum of car (A + B) we make use of the trigonometric formula cos θ = (momentum of car B) / (momentum of car (A +B))
therefore momentum of car (A+B) = (momentum of car B) / (cos θ)
momentum of car (A+B) = 25,500 / cos 30
= 29,444.87 kgm/s
recall that momentum = mass x velocity
therefore velocity of (A+B) = mass of (A+B) / momentum of (A+B)
velocity (A+B) = 3,400 / 29,444.87
= 8.66 m/s
- To find out how fast car A was moving we have to find its momentum from the second diagram using Pythagoras theorem.
momentum of A = [tex]\sqrt{momentum of (A+B)^{2} - momentum of B\\^{2} }
momentum of A = [tex][tex]\sqrt{29,444.87^{2}- 25500^{2}}[/tex]
momentum of A = 14,722.44 kgm/s
recall that momentum = mass x velocity
therefore velocity of car A = momentum / mass
= 14,722.44 / 1,900
= 7.75 m/s
