Texting and Driving

Physics of Paying Attention

Stopping DistanceReaction time Lab

SCENARIO

• Imagine your traveling in a car at 68mi/hr and you look away for one second to [change the radio station / check a text message / to look at the pretty trees / or any reason], why is it a bad idea to do this?

Physics

1. Distance traveled in a second.2. Human Reaction Time3. Breaking Distance.

Distance Traveled

1. 68mi/hr is the same as 100ft/s.

So in that second you travel 100 feet!

€

68mi

1hr∗5,280 ft

1mi∗1hr

60min∗1min

60s=100 ft

1s

Reaction Time

1. Perception time (recognize the danger)

2. Reaction time (decide what to do)

3. Action time (pushing the break pedal).

You are moving 100ft/s while this is going on!

1s = 100 more feet

Breaking DistanceWORK AND KINETIC ENERGY

(KE = ½ mv2) (W=Fd)

Breaking Distance

1. At 68mi/hr its about 250ft.2. This assumes:

--roads are dry --your tires are in optimal shape

--your breaks are good.

Stopping Distance 68mi/hr

1. 100 feet (looking away for a second).2. 100 feet (thinking and reacting).3. 250 feet (breaking distance).

450 total feet to stop!

Stopping Distance 35mi/hr

1. ~50 feet (looking away for a second).2. ~50 feet (thinking and reacting).3. ~60 feet (breaking distance).

160 total feet to stop!