What will be a railroad car's speed when....?

1 ⤊

What will be a railroad car's speed when....?

The railroad car has a mass of 13,500 kg. It travels alone on a level frictionless track with a constant speed of 17.0 m/s. A 5,500 kg additional load is dropped onto the car. What is the car's new speed???

Can't get the answer... please help ASAP. Thanks!!!

2006-12-18 11:36:30 · 2 answers · asked by abc123 1 in Science & Mathematics ➔ Physics

2 answers

Old mass = 13500
New mass = 19000

I would imagine the answer is 17 x 13500 / 19000 = 12.1 m/s to one decimal place.

2006-12-18 11:41:21 · answer #1 · answered by teef_au 6 · 0⤊ 0⤋

this is momentum

which says

m1v1 + m2v2 = m1v1(final) + m2v2(final)

13500(17) + 0 = vf(13500+5500)

vf = 13500(17)/19000

vf=12.07m/s

2006-12-18 12:09:17 · answer #2 · answered by coolchap_einstein 3 · 1⤊ 0⤋