just a couple of questions. my teacher is out of town so i dont wanna bug her. they're multiple choice.
Which of the following is not an example of kinetic energy?
sound
chemical energy
radiant energy
heat
What energy conversion is occurring when energy is given off from the sun?
Nuclear energy is converted to thermal energy.
Nuclear energy is converted to radiant energy.
Radiant energy is converted to thermal energy.
Radiant energy is converted to nuclear energy.
If a measurement is said to be precise, this means that it is
consistent with other measurements that were made.
considered accurate enough to be reported.
close to the correct or accepted value of the measurement.
measured very carefully and can have more sig figs in the value.
Which of the following is not an example of kinetic energy?
sound
chemical energy
radiant energy
heat
What energy conversion is occurring when energy is given off from the sun?
Nuclear energy is converted to thermal energy.
Nuclear energy is converted to radiant energy.
Radiant energy is converted to thermal energy.
Radiant energy is converted to nuclear energy.
If a measurement is said to be precise, this means that it is
consistent with other measurements that were made.
considered accurate enough to be reported.
close to the correct or accepted value of the measurement.
measured very carefully and can have more sig figs in the value.
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I used to be a chemistry teacher, and these are very common questions.
1. Basically, kinetic energy is energy of motion (or energy that is doing work), as contrasted with potential energy, which is stored up energy (or more precisely, energy of position). The way the question is worded tells you that only one answer provided is an example of potential energy. Sound, heat, and radiant energy all involve waves or molecules/atoms moving. Notice I said "moving" so they are kinetic. Chemical energy is stored in the bonds between atoms. Notice here that I said "stored" so it is potential energy.
2. Radiant energy is energy given off from a source as electromagnetic radiation (for example, visible light, ultraviolet, etc.). Nuclear energy is the energy from nuclear reactions in which matter is converted into energy. Thermal energy is just heat (from movement of molecules/atoms).
Ok, so what happens on the sun? Nuclear reactions! So the conversion starts with nuclear energy. So, what happens next? I think this is a bit of a trick question on your teacher's part. As a result of the nuclear reaction, both heat and light (visible and ultraviolet) are given off. So, nuclear is converted into both thermal and radiant energy (as light). So there are two answers to this question.
3. In science, it is important to remember that accuracy and precision are two different things (so the second choice can be rules out). Accuracy is closeness to the correct or accepted value of the measurement (so you can rule that one out). Precision is defined as the closeness of several measurements to each other. A good way to visualize these two concepts is with a dart board (I used to have a student do this in my class with the nerf sticky darts). The dart close to the bullseye is accurate. If the darts are all close together, then the person has good precision (but not necessarily accuracy--they may be far from the bullseye).
Hope this helps to clear up your confusion!
1. Basically, kinetic energy is energy of motion (or energy that is doing work), as contrasted with potential energy, which is stored up energy (or more precisely, energy of position). The way the question is worded tells you that only one answer provided is an example of potential energy. Sound, heat, and radiant energy all involve waves or molecules/atoms moving. Notice I said "moving" so they are kinetic. Chemical energy is stored in the bonds between atoms. Notice here that I said "stored" so it is potential energy.
2. Radiant energy is energy given off from a source as electromagnetic radiation (for example, visible light, ultraviolet, etc.). Nuclear energy is the energy from nuclear reactions in which matter is converted into energy. Thermal energy is just heat (from movement of molecules/atoms).
Ok, so what happens on the sun? Nuclear reactions! So the conversion starts with nuclear energy. So, what happens next? I think this is a bit of a trick question on your teacher's part. As a result of the nuclear reaction, both heat and light (visible and ultraviolet) are given off. So, nuclear is converted into both thermal and radiant energy (as light). So there are two answers to this question.
3. In science, it is important to remember that accuracy and precision are two different things (so the second choice can be rules out). Accuracy is closeness to the correct or accepted value of the measurement (so you can rule that one out). Precision is defined as the closeness of several measurements to each other. A good way to visualize these two concepts is with a dart board (I used to have a student do this in my class with the nerf sticky darts). The dart close to the bullseye is accurate. If the darts are all close together, then the person has good precision (but not necessarily accuracy--they may be far from the bullseye).
Hope this helps to clear up your confusion!