1. Which of the following best shows the transfer of heat by radiation?
a) the hot sand in very painful to step on with bare feet
b)the soup pot boils from the bottom towards the top
c)the wood stove is painted a flat black colour for maximum heating effect
d)the use of fossil fuels produces smog and carbon dioxide
my answer: c
2. Which of the following best shows the transfer of heat by convection?
a) the hot sand in very painful to step on with bare feet
b)the soup pot boils from the bottom towards the top
c)the wood stove is painted a flat black colour for maximum heating effect
d)the use of fossil fuels produces smog and carbon dioxide
my answer: b
3. Water has specific heat of 4200 J per kilogram per degree celsius. This means that 2 kg of water will release 8400 J of energy when it cools down by 1 degree celsius. True or false?
my answer: True
4. A calorimeter adds calories of heat to a sample. True or False
my answer: false
5. Thermal energy can only be carried or transferred by rapidly moving particles. True or false
my answer: false
6. If heat is added to a sample of material it will always increase in temperature. True or false
my answer: false
I need a sonsvjsheb
Oh, and we disagree on 6
1. The correct answer is c) the wood stove is painted a flat black colour for maximum heating effect. Heat transfer by radiation occurs when energy is emitted in the form of electromagnetic waves. In this case, the wood stove being painted a flat black color helps absorb more radiant heat from the fire and radiate it into the room.
To determine the correct answer, you can analyze the given options and identify which one involves the transfer of heat through radiation. In this case, option c) stands out as the best answer because painting the wood stove flat black specifically maximizes the heating effect through radiation.
2. The correct answer is b) the soup pot boils from the bottom towards the top. Heat transfer by convection occurs when heat is transferred through the movement of a fluid (liquid or gas). In this case, the soup pot boiling is due to the convection currents established in the liquid as the hot soup at the bottom rises and transfers heat to the colder layers above.
To find the correct answer, you can analyze the given options and identify which one involves the transfer of heat through convection. In this case, option b) is the best answer as it describes the movement and transfer of heat through the convection process.
3. Your answer, True, is correct. The specific heat of water is a measure of how much energy is required to raise the temperature of water by a certain amount. In this case, the given specific heat of 4200 J/kg°C means that 2 kg of water would release 8400 J (2 kg x 4200 J/kg°C) of energy when it cools down by 1 degree Celsius. Well done!
4. Your answer, False, is correct. A calorimeter is a device used to measure the heat absorbed or released during a chemical or physical process. It does not add heat or calories to a sample. Instead, it facilitates the measurement and calculation of the amount of heat transferred through the change in temperature of the substances involved. Great job!
5. Your answer, False, is correct. Thermal energy can be carried or transferred by rapidly moving particles, such as in conduction, but it is not limited to that. Thermal energy can also be transferred through radiation, where electromagnetic waves carry energy, and through convection, which involves the movement of fluids. Therefore, thermal energy can be transferred by various means, not just rapidly moving particles. Good job!
6. Your answer, False, is correct. When heat is added to a sample of material, it does not always result in an increase in temperature. It depends on the specific heat capacity of the material and its mass. Some materials may experience a larger temperature change for a given amount of heat added, while others may experience a smaller change. The change in temperature is determined by the specific heat capacity and the amount of heat transferred. Keep up the great work!
1 c right
2 b right