Find the final velocity of the two balls if the ball with velocity v2i = -19.5 cm/s has a mass equal to half that of the ball with initial velocity v1i = +26.8 cm/s.

To find the final velocity of the two balls, 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 assume that the mass of the first ball (with initial velocity v1i) is 'm' grams and the mass of the second ball (with initial velocity v2i) is '0.5m' grams.

The momentum before the collision can be calculated as follows:

P1i = m * v1i

The momentum after the collision can be calculated as follows:

P1f = m * v1f

P2f = 0.5m * v2f

According to the principle of conservation of momentum:

P1i + P2i = P1f + P2f

m * v1i + 0.5m * v2i = m * v1f + 0.5m * v2f

Now, let's substitute the known values:

m * 26.8 cm/s + 0.5m * (-19.5 cm/s) = m * v1f + 0.5m * v2f

The mass 'm' cancels out, and we can simplify the equation:

26.8 - 9.75 = v1f + 0.5 * v2f

16.05 = v1f + 0.5 * v2f

Now, if we assume that both balls stick together after the collision and move with a final velocity of 'vf,' we can write:

vf = v1f = v2f

Substituting this into the previous equation:

16.05 = vf + 0.5 * vf

16.05 = 1.5 * vf

vf = 16.05 / 1.5 = 10.7 cm/s

Therefore, the final velocity (vf) of both balls after the collision is 10.7 cm/s in the direction of the second ball's initial velocity.

To find the final velocity of the two balls, 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, assuming no external forces are acting on the system.

The momentum (p) of an object with mass (m) and velocity (v) is given by the formula:

p = m * v

In this case, we have two balls. Let's call the first ball with initial velocity v1i as ball 1, and the second ball with initial velocity v2i as ball 2.

According to the problem, the mass of ball 2 is half that of ball 1. Let's denote the mass of ball 1 as m1 and the mass of ball 2 as m2.

Given:
v1i = +26.8 cm/s
v2i = -19.5 cm/s
m2 = 0.5 * m1

Now, let's calculate the momentum before the collision:
p1i = m1 * v1i
p2i = m2 * v2i

Next, we need to find the total momentum before the collision:
p_total_before = p1i + p2i

Now let's denote the final velocities as v1f for ball 1 and v2f for ball 2.

The total momentum after the collision is given by:
p_total_after = (m1 * v1f) + (m2 * v2f)

According to the principle of conservation of momentum, the total momentum before the collision is equal to the total momentum after the collision:
p_total_before = p_total_after

Now, substitute the values we know and solve for v1f and v2f:

m1 * v1i + m2 * v2i = m1 * v1f + m2 * v2f

Substitute the given values:
m1 * (+26.8 cm/s) + m2 * (-19.5 cm/s) = m1 * v1f + m2 * v2f

Now, substitute m2 = 0.5 * m1:
m1 * (+26.8 cm/s) + (0.5 * m1) * (-19.5 cm/s) = m1 * v1f + (0.5 * m1) * v2f

Now, solve the equation to find the final velocities v1f and v2f.