In the railroad freight yard, an empty freight car of mass m rolls along a straight level track at 1.1 m/s and collides with an initially stationary, fully loaded boxcar of mass 4.3m. The two cars couple together upon collision.

(a) What is the speed of the two cars after the collision?

m/s

I believe it's m1(v1)+4.3(1.1)/m1+4.3 but i don't know what m1 and v1 would be?

m1•v1+ 0 =(m1+m2) •V,

V = m1•v1/(m1+m2) = 1.1•m/5.3m=0.21 m/s

Thank you!

To find the speed of the two cars after the collision, we can use the principle of conservation of momentum. According to this principle, the total momentum before the collision is equal to the total momentum after the collision.

Let's assign some variables to the given information:
m = mass of the empty freight car (in kg)
v1 = initial speed of the empty freight car (1.1 m/s)
4.3m = mass of the fully loaded boxcar (in kg)
vf = final speed of both cars after the collision (in m/s)

Using the principle of conservation of momentum, we can write the equation as:

(m * v1) + (4.3m * 0) = (m + 4.3m) * vf

Since the initial speed of the fully loaded boxcar is 0 (as it is initially stationary), we can simplify the equation to:

m * v1 = 5.3m * vf

Now, let's solve for vf:

vf = (m * v1) / (5.3m)

The "m" cancels out, giving us:

vf = v1 / 5.3

Substituting the given value for v1 (1.1 m/s):

vf = 1.1 / 5.3

Now we can calculate this value:

vf ≈ 0.2075 m/s

Therefore, the speed of the two cars after the collision is approximately 0.2075 m/s.