An engineer is testing the density of five different solid polymer spheres, A, B, C, D, and E, to determine their suitability for marine equipment.
The engineer plots the density of each sphere on a bar chart:
The spheres are placed into a container filled with an unknown liquid mixture. The engineer observes that:
- Spheres A and C float.
- Spheres B, D, and E sink.
Explain why some solid spheres float and some sink when placed in a liquid.
Use the bar chart to estimate the range of the density of the liquid mixture used.
The engineer has access to five pure liquids in the laboratory:
| Liquid | Density (kg/m3\text{kg/m}^3kg/m3) |
|---|---|
| Hexane | 650 |
| Ethanol | 790 |
| Pure Water | 1000 |
| Glycerol | 1260 |
| Bromoform | 2890 |
In which of these liquids would all five spheres (A, B, C, D, and E) float?
A pressure sensor in a water reservoir is lowered from a depth of 4.5 m to a depth of 12.5 m.
Calculate the change in pressure experienced by the sensor.
Use the gravitational field strength g=9.8 N/kgg = 9.8\text{ N/kg}g=9.8 N/kg and the density of water ρ=1000 kg/m3\rho = 1000\text{ kg/m}^3ρ=1000 kg/m3.