PHY 150 M7 Momentum Lab Report

Momentum

Activity 1: Elastic Collision with Equal Masses Data Table 1 Table 1A. Cart A before collision. Cart A mass, m (kg) Distance, d (m) Time, t (s) Average time, t (s) Velocity = d/t (m/s) v A 0.0591 kg 0.5 m Trial 1: 0.35 s 0.337 s 0.5 m / 0.337 s = 1.48 m/s Trial 2: 0.33 s Trial 3: 0.33 s Table 1B. Cart A after collision. Cart A mass, m (kg) Distance, d (m) Time, t (s) Average time, t (s) Velocity = d/t (m/s) v A ’ 0.0591 kg 0.00 m Trial 1: 0.27 s 0.250 s 0.00 m / 0.25 s = 0.00 m/s Trial 2: 0.24 s Trial 3: 0.24 s Table 1C. Cart B after collision. Cart B mass, m (kg) Distance, d (m) Time, t (s) Average time, t (s) Velocity = d/t (m/s) v B ’ 0.0582 kg 0.5 m Trial 1: 0.38 s 0.383 s 0.5 m / 0.383 s = 1.305 m/s Trial 2: 0.38 s Trial 3: 0.39 s Calculations for Activity 1. Elastic Collision with Equal Masses Apply the law of conservation of momentum to the two-cart system by calculating the momentum before and after the collision. Helpful equations : Momentum before the collision = 𝑚 𝐴 𝒗 𝐴 + 𝑚 𝐵 𝒗 𝐵 Momentum after the collision = 𝑚 𝐴 𝒗 𝐴 ′ + 𝑚 𝐵 𝒗 𝐵 ′ 𝑚 𝐴 𝒗 𝐴 + 𝑚 𝐵 𝒗 𝐵 = 𝑚 𝐴 𝒗 𝐴 ′ + 𝑚 𝐵 𝒗 𝐵 ′ Percent difference = | first value − second value first value + second value 2 | x 100% 1. Calculate the momentum of the system before the collision (the left side of the equation) and after the collision (the right side of the equation). Before: 0.0591 kg ∗ 1.48 m s + 0.0591 kg ∗ 0.0 m s = 0.087 After: 0.0591 kg ∗ 0 m s + 0.0582 ∗ 1.305 m s = 0.076 2. Calculate the percent difference between the two values. 1 © 2016 Carolina Biological Supply Company

Percent difference = | first value − second value first value + second value 2 | x 100% 1. Calculate the momentum of the system before the collision (the left side of the equation) and after the collision (the right side of the equation). Before: 0.22 kg ∗ 1.90 m s + 0.22 kg ∗ 0.0 m s = 0.418 After: 0.22 kg ∗ 0.53 m s + 0.0582 kg ∗ 2.00 m s = 0.349 2. Calculate the percent difference between the two values. | 0.418 − 0.349 0.418 + 0.349 2 | ∗ 100% = 4.49% 3. Explain any difference in the values before and after the collision. Cart A continued to have velocity after the collision due to the increased mass in relation to cart B. Activity 3: Elastic Collision: Mass Added to Cart B Data Table 3 Table 3A. Cart A before collision. Cart A mass, m (kg) Distance, d (m) Time, t (s) Average time, t (s) Velocity = d/t (m/s) v A 0.0591 kg 0.5 m Trial 1: 0.19 s 0.207 s 0.5 m / 0.207 s = 2.415 m/s Trial 2: 0.21 s Trial 3: 0.22 s Table 3B. Cart A after collision. Cart A mass, m (kg) Distance, d (m) Time, t (s) Average time, t (s) Velocity = d/t (m/s) v A ’ 0.0591 kg -0.10 Trial 1: 0.27 s 0.297 s -0.10 m/0.297 s = -0.0297 m/s Trial 2: 0.31 s Trial 3: 0.31 s Table 3C. Cart B after collision. Cart B mass, m (kg) Distance, d (m) Time, t (s) Average time, t (s) Velocity = d/t (m/s) v B ’ 0.362 kg 0.35 m Trial 1: 0.67 s 0.677 0.35 m / 0.677 s = 0.517 m/s Trial 2: 0.67 s 3 © 2016 Carolina Biological Supply Company

Cart B mass, m (kg) Distance, d (m) Time, t (s) Average time, t (s) Velocity = d/t (m/s) v B ’ Trial 3: 0.69 s Calculations for Activity 3. Elastic Collision: Mass Added to Cart B . Apply the law of conservation of momentum to the two-cart system by calculating the momentum before and after the collision. Helpful equations : Momentum before the collision = 𝑚 𝐴 𝒗 𝐴 + 𝑚 𝐵 𝒗 𝐵 Momentum after the collision = 𝑚 𝐴 𝒗 𝐴 ′ + 𝑚 𝐵 𝒗 𝐵 ′ 𝑚 𝐴 𝒗 𝐴 + 𝑚 𝐵 𝒗 𝐵 = 𝑚 𝐴 𝒗 𝐴 ′ + 𝑚 𝐵 𝒗 𝐵 ′ Percent difference = | first value − second value first value + second value 2 | x 100% 1. Calculate the momentum of the system before the collision (the left side of the equation) and after the collision (the right side of the equation). Before: 0.0591 kg ∗ 2.415 m s + 0.0591 kg ∗− 0.0297 m s = 0.445 After: 0.0591 kg ∗− 0.0297 m s + 0.362 kg ∗ 0.517 m s = 0.185 2. Calculate the percent difference between the two values. | 0.445 − 0.185 0.445 + 0.185 2 | ∗ 100% = 41.27% 3. Explain any difference in the values before and after the collision. a. The increased mass of cart b absorbed the smaller mass of cart a. Questions for Momentum : 1. The law of conservation of momentum states that the total momentum before a collision equals the total momentum after a collision provided there are no outside forces acting on the objects in the system. What outside forces are acting on the present system that could affect the results of the experiments? Outside forces acting on the present system are friction of the traveling surface and differences in mass between objects. 4 © 2016 Carolina Biological Supply Company