Question

A car with a mass of 980 kg is initially traveling east toward an intersection with a speed of v_c = 20.9 m/s and a 1500 kg pickup is traveling north toward the same intersection. The car and truck collide at the intersection and stick together. After the collision, the wreckage (car and truck) moves off in a direction of 44.0° above the x-axis.

Determine the initial speed of the truck and the final speed of the wreckage in meters per second.

initial speed of the truck
See if you can write a statement of conservation of momentum in both the x and y direction and then eliminate the final speed of the wreckage in order to determine the initial speed of the truck. m/sfinal speed of the wreckage
The final speed of the wreckage can be determined from either the x or y statement of conservation of momentum. m/s

First guy that tried this got 11.48 as initial and 13.8 as final. - Incorrect

Answer 1

(mm) usino. = 20.9 m/ m = 980kg (mmy) v caso tm= 1500kg Applying conservation of momentum along x-axis me = (m + m) vaso (980) (20.9) = (2480) v cosuu v (980) (20.9) – 20482 (2480) (cosu 4) 1783.96 final wel of wreckage v = 11.48 me Along y-axis mg = (m + m) usino 1500 Ut -(2480) (11.48) (0.6946) VI - 19777.20 1500 ( = 13. 185 m/s Initial vel. ruck