Question

NASA's Parker Solar Probe is currently en route to the outer corona of the sun. At its closest approach it will be traveling at 7.00 x 105 km/hr. How fast will it be going in units of mi/s? 5,280 feet = 1 mile

Answer 1

`120.822(mi)/(s)` will be the speed in
`(mi)/(s)`

Step-by-step explanation:

This is a unit conversion problem.

To solve it, we need the equivalences between km and ft, ft and mi and hr and s.

The equivalences are :

`5280 ft=1 mi\\1km=3280.84 ft\\1hr=60 min\\1min=60s`

If
`5280ft=1mi` then

`(5280ft)/(1mi)=1\\(1mi)/(5280ft)=1`

The trick is to multiply by one the speed given until to convert it in mi/s units

`(7.00).10^(5)(km)/(hr).(3280.84ft)/(1km).(1mi)/(5280ft).(1hr)/(60min).(1min)/(60s)=120.822(mi)/(s)`

Notice that km,ft,hr and min have been cancelled.

Be careful of the fraction order.

Multiply by ft/km is different that multiply by km/ft