Your answer is here :
The speedometer of a auto mobile measures the speed of the auto mobile
As well speed = distance / time
hope it helps uh
A speedometer or a speed meter is a gauge that measures and displays the instantaneous speed of a vehicle.
God bless you
Explanation: it is used to measure the speed of an vehicle
ᴍᴇᴀsᴜʀᴇ ᴛʜᴇ sᴘᴇᴇᴅ ᴏғ ᴛʜᴇ ᴄᴀʀ
it reads speed in km/h.
hope this will help.