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A 20 g ball of clay traveling east at 5.5 m/s collides with a 55 g ball of clay traveling north at 2.0 m/s. What is the speed of the resulting 75 g ball of clay? Express your answer with the appropriate units. v = ______ What is the direction of the resulting ball of clay? θ = _____

User VilleKoo
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We can use conservation of momentum to solve this problem. The total momentum before the collision is given by:

p_before = m1 * v1 + m2 * v2

where m1 = 20 g = 0.02 kg, v1 = 5.5 m/s to the east, m2 = 55 g = 0.055 kg, and v2 = 2.0 m/s to the north. We can resolve the velocity of the second ball into its east and north components:

v2_east = 0

v2_north = 2.0 m/s

So we have:

p_before = 0.02 kg * 5.5 m/s + 0.055 kg * 2.0 m/s = 0.2215 kg·m/s to the east + 0.11 kg·m/s to the north

After the collision, the two balls stick together and move off in some direction at some speed v. The total momentum after the collision is given by:

p_after = (m1 + m2) * v

where m1 + m2 = 0.075 kg.

Since momentum is conserved, we can equate p_before and p_after:

p_before = p_after

0.2215 kg·m/s to the east + 0.11 kg·m/s to the north = 0.075 kg * v

To solve for v, we can take the magnitude of both sides of the equation:

sqrt[(0.2215 kg·m/s)^2 + (0.11 kg·m/s)^2] = 0.075 kg * v

v = sqrt[(0.2215 kg·m/s)^2 + (0.11 kg·m/s)^2] / 0.075 kg

v = 3.27 m/s

So the speed of the resulting ball of clay is 3.27 m/s. To find its direction, we can use trigonometry. Let θ be the angle between the direction of motion of the resulting ball and the eastward direction. Then we have:

tan(θ) = (0.11 kg·m/s) / (0.2215 kg·m/s)

θ = tan^(-1)[(0.11 kg·m/s) / (0.2215 kg·m/s)]

θ = 25.2 degrees north of east

So the direction of the resulting ball of clay is 25.2 degrees north of east.

User Marc Intes
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