Use the worked example above to you solve this problem. find the energy transferred in 1 h by conduction through a concrete wall 1.6 m high, 4.00 m long, and 0.20 m thick if one side of the wall is held at 20°c and the other side is at 5°c.

The energy transferred is 2.93 MJ.

Explanation:

Given that,

Time = 1 h = 3600 s

Area

Width

Temperature

For concrete wall,

The thermal conductivity

k = 1.7 W/mK

Using Fourier's law

Where, A = area

= width

= change in temperature

k = thermal conductivity

Put the value into the formula

The energy transferred in 1 hour

Hence, The energy transferred is 2.93 MJ.

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west