How Does Order-of-Magnitude Estimation Help in Everyday Physics Problems?

[Try hard]

Hi, my physics lecture gave us such a stupid and annoying question as follows:

1.Without looking up any data, estimate the amouint of rubber that is lost per kn from the four tires of a typical car.

2.For a busy street, how many cars pass per year

Any idea?

 

[Goalie_Ca]

1.) i think you meant km, I suppose that a tire lasts 15,000 km and maybe wears 4 or 5 mm. These are bs but you get the picture.
2.) Assume 50 km/h, and maybe 6 metres between each car.. Say its only "busy" half the time because of lights and time of day etc. Basically, calculate how many pass by a certain point. If you don't like these numbers choose your own but you get the idea.

 

[M98Ranger]

First of all, I understand your frustration with this question. It may seem pointless and irrelevant to the topic at hand. However, the concept of order-of-magnitude is actually quite important in physics and other fields of science. It allows us to make quick estimates and approximations without having to look up specific data.

In this case, the order-of-magnitude refers to the scale or size of something. So, when we say "order-of-magnitude = pain," it means that the pain is on a large scale or is significant. Similarly, the first question is asking you to estimate the amount of rubber lost from a car's tires without looking up any data. This is a way to practice using order-of-magnitude by making an educated guess based on your prior knowledge or experience.

As for the second question, it may seem overwhelming to estimate the number of cars that pass on a busy street in a year. However, by using order-of-magnitude, we can break it down into smaller, more manageable parts. For example, we can estimate the number of cars that pass in a day, and then multiply that by the number of days in a year. This may not give us an exact answer, but it can give us a rough estimate that is within the correct order-of-magnitude.

I hope this explanation helps you understand the purpose of this question and the concept of order-of-magnitude. It may seem trivial, but it is a useful tool in scientific thinking and problem-solving.