E. Heat Transfer Quiz

What is the formula for the rate of heat flow (q) in one-dimensional heat flow at steady-state conditions?

• q = A k/l (t1 - t2)

• q = A l/k (t1 - t2)

• q = A k l (t1 - t2)

• q = A k/l (t2 - t1)

What is the unit of the coefficient of thermal conductivity (k)?

• Watts

• (m²·K)/W

• w/m·K

• Kelvin

What does the term (t1 - t2) represent in the formula for rate of heat flow?

• Flow path length

• Temperature difference across the flow path

• Coefficient of thermal conductivity

• Area perpendicular to heat flow path

What is the formula for thermal resistance (R)?

• R = 1/c = l/k

• R = c = l/k

• R = 1/c = k/l

• R = c = k/l

What is the formula used to calculate the heat flow per square meter of Wall A?

• A/R (t1 - t2)

• A*R (t1 - t2)

• A/R (t2 - t1)

• A*R (t2 - t1)

What is the formula for the instantaneous heat flow rate according to Fourier's Law?

• q = A/R (t1 - t2)

• Q = q x time

• Q = A/R (t1 - t2) x time

• $ = Q x (electricity cost in $/kilo-Watt hour)

In what units is the total heat flow over time most commonly measured?

• Joules

• kilo-Watt hours

• Calories

• BTUs

What is the formula to calculate the heating cost ($)?

• q = A/R (t1 - t2)

• Q = q x time

• Q = A/R (t1 - t2) x time

• $ = Q x (electricity cost in $/kilo-Watt hour)

What is the formula for calculating total heat loss over time?

• Q = q x time

• Q = A/R (t1 - t2) x Time

• Q = A x R (t1 - t2) x Time

• Q = A/R (t1 + t2) x Time

What is the formula for Annual Heat Loss?

• Q = (A/R) (Degree Days)

• Q = (R/A) (Degree Days)

• Q = (A*R) (Degree Days)

• Q = (A/R) (Days)