How much extra water does a 21.5 ft, 175-lb concrete canoe displace compared to an ultra-lightweight 38-lb Kevlar canoe of the same size carrying the same load?

Respuesta :

Answer:

The volume of the extra water is [tex]2.195 ft^{3}[/tex]

Solution:

As per the question:

Mass of the canoe, [tex]m_{c} = 175 lb + w[/tex]

Height of the canoe, h = 21.5 ft

Mass of the kevlar canoe, [tex]m_{Kc} = 38 lb + w[/tex]

Now, we know that, bouyant force equals the weight of the fluid displaced:

Now,

[tex]V\rho g = mg[/tex]

[tex]V = \frac{m}{\rho}[/tex]                                  (1)

where

V = volume

[tex]\rho = 62.41 lb/ft^{3}[/tex] = density

m = mass

Now, for the canoe,

Using eqn (1):

[tex]V_{c} = \frac{m_{c} + w}{\rho}[/tex]

[tex]V_{c} = \frac{175 + w}{62.41}[/tex]

Similarly, for Kevlar canoe:

[tex]V_{Kc} = \frac{38 + w}{62.41}[/tex]

Now, for the excess volume:

V = [tex]V_{c} - V_{Kc}[/tex]

V = [tex]\frac{175 + w}{62.41} - \frac{38 + w}{62.41} = 2.195 ft^{3}[/tex]