How To Approach Units and Problem Solving Questions?

AI Thread Summary
When learning physics, understanding the units and physical quantities is crucial for problem-solving. It's acceptable to look up constants and measurements when necessary, as many problems will provide these values. However, memorizing key unit conversions and fundamental constants is beneficial for efficiency. Knowing the meaning of physical quantities and their units is essential for grasping the concepts. Overall, a balance of memorization and reference is recommended for effective learning in physics.
Wiggins2Magic
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Hey everyone,

I'm starting to learn physics on my own and I'm doing the chapter review questions at the end of the chapter. Right now, I'm on units and problem solving. My question to you guys is should I be concerned about actually knowing the exact measurement to solve the problems, or is it okay for me to Google the measurements and then solve them?

Thanks
 
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Wiggins2Magic said:
Hey everyone,

I'm starting to learn physics on my own and I'm doing the chapter review questions at the end of the chapter. Right now, I'm on units and problem solving. My question to you guys is should I be concerned about actually knowing the exact measurement to solve the problems, or is it okay for me to Google the measurements and then solve them?

Thanks

What measurements exactly are you talking about? I am bit confused as to exactly what you are asking for. If you are talking about constants such as the speed of light in a vacuum, then usually the question will tell you what to you use for that value.
 
Can you rephrase the question?

Are you asking if you need to memorise the units for some physical quantities? If that is the question then the answer is yes.

If you are asking do you need to know the value of constants then probably not. Usually the question will give you that value of constants you need or you can look them up.
 
You certainly need to know what the "physical quantity" means and I don't see how you can do that without knowing its units.
 
Some units and constants are worth remembering some are not. It is hard to generalize. Certainly you should know things like 1 km= 1000m and 32°F=0°C. I don't know what books some of you are reading. You mean in such books they say things like "you might need to use pi in this question use the value 3.14" I do not think that is usual.
 
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