Physics Energy 2 Flashcards
(17 cards)
What is thermal conductivity?
A measure of how well a material conducts energy when it is heated
Higher thermal conductivity results in a higher rate of energy transfer by conduction.
What factors affect the rate of energy transfer by conduction through insulation material?
- Temperature difference across the material
- Thickness of the material
- Thermal conductivity of the material
True or False: A larger temperature difference increases the rate of energy transfer by conduction.
True
Fill in the blank: The thicker the material, the _______ the rate of energy transfer by conduction.
lower
List ways to reduce energy loss in homes.
- Loft insulation
- Energy efficient boiler
- Cavity wall insulation
- Install solar panels
- Double glazing
- Draft excluders
What is the specific heat capacity of a substance?
The amount of energy required to raise the temperature of one kilogram of the substance by one degree Celsius
What is the equation for change in thermal energy?
ΔE = m x c × Δθ
In the equation ΔE = m x c × Δθ, what does ‘m’ represent?
Mass in kilograms, kg
In the equation ΔE = m x c × Δθ, what does ‘Δθ’ represent?
Change in temperature in degrees Celsius, °C
Fill in the blank: Specific heat capacity is measured in _______.
Joules per kilogram per degree Celsius, J/(kg°C)
How do you rearrange the equation ΔE = m x c × Δθ to solve for specific heat capacity (c)?
c = ΔE / (m x Δθ)
What is the specific heat capacity of a material if 4000J changes the temperature of 2kg by 3°C?
667 J/(kg°C)
What is the aim of the specific heat capacity required practical?
Determine the specific heat capacity of one material
What is the independent variable in the specific heat capacity investigation?
Material
What equipment is needed for the specific heat capacity practical?
- Joulemeter
- Immersion Heater
- Metal Block
- Thermometer
List the steps in the method for determining specific heat capacity.
- Measure the mass of the block using a balance
- Measure the starting temperature of the block using a thermometer
- Increase the temperature of the block using an immersion heater
- Measure the energy input using a Joulemeter
- Record the end temperature and calculate the temperature difference
- Use the equation to find the specific heat capacity
What improvements can be made to the specific heat capacity investigation?
- Wrap the block in insulation to minimize heat loss
- Repeat investigation and calculate an average to reduce random error
