# Homework Help: Conversion methods

1. Sep 15, 2007

### wiskeywiz

cant get around this problem: convert 40km/h to ft/sec.

2. Sep 15, 2007

### cristo

Staff Emeritus
Well, the units are $$\frac{km}{h}$$ so you need to convert the km to feet and hours to seconds, then plug them into that fraction.

3. Sep 15, 2007

### Danger

If you need help in converting the units, Google has a built-in conversion programme. In the search field, you can just enter something like 'how many feet in a kilometer' and it will tell you.
There's also a really awesome converter on line, which someone here in PF was kind enough to provide a link to. Unfortunately, that's on my iBook bookmark list and I'm now on the PC at work. If it doesn't show up before, I'll find it when I get home and post it here.

4. Sep 15, 2007

### wiskeywiz

(40km/1h)x(1mile/1.609344km)=24.85484769m/h ??

5. Sep 15, 2007

### wiskeywiz

aw thats cool. atleast i have an answer to check my work by thanx!

6. Sep 15, 2007

### cristo

Staff Emeritus
Yes, that's correct. Although, a quicker way would be to write 40km in metres, then convert metres to feet (since, I imagine, you know how many metres in a km, but not how many feet in a mile). Then do the same for the time.

7. Sep 15, 2007

### wiskeywiz

so 24.85484769 X 5280 = 131,233.59580ft/hr. ?

8. Sep 15, 2007

### wiskeywiz

and that number divided by 3600sec/hr = 36.45377----ft/sec.

9. Sep 15, 2007

### cristo

Staff Emeritus
Yup, that's correct (but I guess you checked that using google: "40 km/h in feet/s")