Thermal Energy and Heat Transfer

The video tutorial explains the construction of a heater with a resistor in an aluminum casing, immersed in ethylene glycol. It describes the process of reaching equilibrium temperatures and the application of voltage to the heater. The tutorial then formulates an equation to calculate the change in internal energy of the ethylene glycol and aluminum, using specific heat, density, and volume. Finally, it solves for the time the heater was on, using power, voltage, and resistance, and converts the result from seconds to minutes.

What is the primary material used in the construction of the heater casing?

• Copper

• Aluminum

• Steel

• Plastic

What is the initial equilibrium temperature of the system before the heater is turned on?

• 32 degrees C

• 58 degrees C

• 73 degrees C

• 24 degrees C

Which formula is used to express the change in internal energy?

• mass x velocity

• mass x specific heat x delta T

• volume x density x specific heat x delta T

• pressure x volume

What is the density of ethylene glycol used in the calculations?

• 2.71 grams per cubic centimeter

• 1.11 grams per cubic centimeter

• 0.91 grams per cubic centimeter

• 1.00 grams per cubic centimeter

What is the specific heat capacity of aluminum used in the calculations?

• 905 J/kg°C

• 500 J/kg°C

• 1000 J/kg°C

• 2360 J/kg°C

What is the expression for power using voltage and resistance?

• I^2 x R

• V / R

• V x I

• V^2 / R

What is the final equilibrium temperature of the system after the heater is turned off?

• 32 degrees C

• 73 degrees C

• 24 degrees C

• 58 degrees C

How is the time calculated in the energy balance equation?

• By multiplying power by time

• By dividing energy change by power

• By adding voltage and resistance

• By dividing power by voltage

What is the final calculated time in minutes for which the heater was on?

• 8.14 minutes

• 10.5 minutes

• 5.6 minutes

• 12.3 minutes

What conversion factor is used to change the time from seconds to minutes?

• Subtract 60

• Multiply by 60

• Divide by 60

• Add 60