The method and the results are on the fluid mechanics lab. Do the analysis yourself first, then check the answers below.
Quick answer: Fluids obey a few linked rules: density is mass per volume, pressure rises with depth as P = P₀ + ρgh, buoyant force equals the weight of fluid displaced, continuity says Av is constant in a pipe, and Bernoulli shows that faster flow means lower pressure. These answers go with the AP Physics 1 lab on fluid mechanics: the graph, the calculations, the uncertainties and the conclusion explained, for all 7 analysis questions.
Sample values come from the data table. If your own results are slightly different, check that the line goes through the origin and that your gradient is close to 9.8 × 10³ N/m³. Always show the method before the final number.
Level: AP Physics 1 (algebra-based) · Curriculum: AP P1 Unit 8
B is a difference of two readings, so its absolute uncertainty is ±0.02 N. For 10 cm³: 0.02/0.10 = 20 %. For 50 cm³: 0.02/0.49 = 4 %. Larger objects give a better measurement.
Question 6 Effect of bubbles
Bubbles add displaced volume, so the upward force is larger and Wwater is smaller. B is too large, so the calculated density of water is too high.
Question 7 Salt water prediction
B = ρVg = 1100 × 5.0 × 10⁻⁵ × 9.81 = 0.54 N, which is 10 % larger than in fresh water.
