Convert unit measures for a problem from zill

Reuben Brennan

Reuben Brennan

Answered question

2022-03-28

Convert unit measures for a problem from zill book
I have the solution, but I don't understand it, I don't understand the part which implies the conversion of unit measures. I know that I can g=32fts2, but then what? So my questions are:
1. how to compute (convert unit measures) 4pound32fts2 to become 18?
pound is a unit measure for weight, ft is for distance (like meter), s is for time. So, how they (in image) simplify that raport - division?
2. Then, for the next step: I know that ω2=km, with m=18 slug and k=16lbft. But what about this division:
km=16lbft18slug=128lbslugft
And again, how can I make this division? lb and slug are units of measure for weight and ft is for distance. How can I reduce them?

Answer & Explanation

Nunnaxf18

Nunnaxf18

Beginner2022-03-29Added 18 answers

Step 1
As I said in my comment, lb is a measure for weight, i.e., a measure for force, while slug is a measure for mass. The problem is that in common talk we do not make a distinction between them. Given that 1 slug=1 lb s2ft,
it's easy to obtain
Step 2
16lbft18slug=128lbftlb s2ft=1281s2.
As I'm not a physicist myself, I don't know if these are the units to be expected.

cineworld93uowb

cineworld93uowb

Beginner2022-03-30Added 16 answers

Step 1
Were the problem and solution written by different people? There's no need to commit to a new mass unit if you know the relations between weight (Fg), mass (m), gravitational acceleration (g), angular frequency (ω), the spring constant (k), and the period (T):
Fg=mgω2=kmT=2πω.
Step 2
That's because you can eliminate m and ω to get
T=2πFggk 2π4 lbf(32 ft s2)(16 lbf ft1) 0.6 s.
The solution you provided has carelessly lost units.

Do you have a similar question?

Recalculate according to your conditions!

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?