Answer:
a. 2873540 seconds are 1.11 days.
b. 215 km/hr= 59.72 m/sec
c. 58.2 km/sec = 93.66 mph
d. 68.45 [tex]\frac{lbm}{ft^{3} }[/tex]= 1097.135 [tex]\frac{kg}{m^{3} }[/tex]
e. 1.362 g/cm= 0.0915 lbm/ft
Explanation:
To convert units, the simplest is to use The Rule of Three, which allows you to work with proportions, such as these cases.
In the case a) : To convert to months, you must first convert to minutes.
60 sec ⇒ 1 minute
2873540 sec ⇒ x
[tex]x=\frac{2873540*1}{60} [/tex]
So x=47892.33 minutes
In the same way, and knowing that 1 hour is 60 minutes, you can know that:
60 minutes ⇒ 1 hour
47892.33 minutes ⇒ x
[tex]x=\frac{47892.33*1}{60}[/tex]
x=798.205 hours
Now, knowing that 1 day is 24 hours and applying the same method, you can know that: 798.205 hours= 33.26 days
And finally, knowing that 1 months have 30 days and applying the same method, you can know that: 33.26 days= 1.11 days
So, you can say that 2873540 seconds are 1.11 days.
Case b):
In first place, you can convert km to m:
1 km ⇒ 1000 m
215 km ⇒ x
x=[tex]798.205=\frac{215*1000}{1}[/tex]
x= 215000 m
And now you have to convert the hour to minutes:
1 hour ⇒ 60 minutes
And: 1 minute ⇒ 60 seconds
60 minutes ⇒ x
[tex]x=\frac{60*60}{1}[/tex]
x=3600 seconds
So 1 hour= 3600 seconds
Now both unit changes are combined.
[tex]215 \frac{km}{hr} = \frac{215000 m}{3600 sec}[/tex]
The result is 215 km/hr= 59.72 m/sec
Case c):
To convert from kilometer per second to kilometer per hour, and knowing that 1 hour= 3600 seconds (case b), you:
3600 sec ⇒ 1 hour
1 sec ⇒ x
So 1 sec= 0.00027 hr
By multiplying the value in kilometers per second by 0.00027, you get 0.0162 km/h
Now you know that 1 km= 0.621371 milla, so using The Rule of Three you can do the unit conversion and you get that 58.2 km/sec = 93.66 mph
Similar to the previous cases, case d) and e) can be resolved.
You have to know that:
1 lbm ⇒ 0.4536 kg
1 [tex]ft^{3}[/tex] ⇒ 0.0283 [tex]m^{3}[/tex]
1 lbm ⇒ 453.6 g
1 ft ⇒ 30.48 cm
So, the results are:
68.45 [tex]\frac{lbm}{ft^{3} }[/tex]= 1097.135 [tex]\frac{kg}{m^{3} }[/tex]
1.362 g/cm= 0.0915 lbm/ft
