6. Determine the thermal conductivity of a 3m x 4m rectangular wall cavity that is 20 inches thick. The rate of heat transfer is 135 J/s, the inside temperature is 74°F and the outside
temperature is 86°F. Note: The unit for thermal conductivity is.

a)  a = 8m/s^2

b) a = 9.8m/s^2

c) a = 200m/s^2

d) a = 9.8m/s^2

Explanation:

Using the laws of newton:

F = ma

where F is the force, m the mass and a the aceleration

a) Solving for the aceleration:

a = F/m

so, replacing the force and the mass of Blanche, we get:

a = 800N/100kg

a = 8m/s^2

b) By the laws of newton, the sumatory of vertical force for Blanche is equal to:

mg = ma

Where g is the gravity

Then, solving for a:

a = g

a = 9.8m/s^2

c) At the same way, solving for the aceleration:

a = F/m

so, replacing the values of the force and the mass of the shot, we get:

a = 800N/4kg

a = 200m/s^2

d) Then, sumatory of vertical force for the shot is equal to:

mg = ma

where g is the gravity

solving for a:

a = g

a = 9.8m/s^2