5.6

5.6 Questions (Collins, p.107)

Notes:
ρfresh water = 1,000kg/m3 
g = 10N/kg 
1,000mbar = 1 bar = 100,000Pa 

Q5) ∆p = h × ρ × g 250000- 100000 = h x 1000 150000 = h x 1000 x 10 
150000/ 1000 = 15m 

Q6) ∆p = h × ρ × g 
∆p = 50 x 420 (0.42x 1000 to change it into kg/m3) x 1.4 
∆p = 294000Pa 
1,000mbar = 1 bar = 100,000Pa so 1,600mbar = 1.6 bar = 160,000Pa 
29,400+160,000 = 189,400Pa TOTAL PRESSURE = 189,400Pa or 189.4 kPa 

5.6 Plenary 

· Which diver experiences the greatest pressure? 

∆p = h × ρ × g 
They both experience the same amount of pressure because the height is the same and we assume that the density and the gravitational field strength will be the same in the 2 places. so therefore the pressure must be the same.