An engineering team is testing a spherical underwater sensor of mass M M\,M and volume VVV. The sensor is fully submerged in various calibration liquids of different densities ρ\rhoρ. In each liquid, the sensor is suspended from a tether, and the tension T T\,T in the tether is measured.
A graph is plotted with tension T T\,T on the vertical (yyy) axis and fluid density ρ \rho\,ρ on the horizontal (xxx) axis. Assuming the sensor's density is always greater than that of the calibration liquids, which mathematical equation represents this relationship, where m m\,m and c c\,c are positive physical constants?
y=mxy = mxy=mx
y=c−mxy = c - mxy=c−mx
y=mx+cy = mx + cy=mx+c
y=mxy = \frac{m}{x}y=xm
54 exam-style questions on Edexcel GCSE Physics 15.2 Pressure in fluids, covering 15.2.1 Atmospheric pressure and height, 15.2.2 Pressure in fluids, 15.2.3 Pressure, force and area, 15.2.4 Pressure and depth, 15.2.5 Pressure in liquids: depth and density, 15.2.6 Upthrust, and 15.2.7 Floating and sinking. Each one has a worked solution and a mark scheme showing where the marks go.