Here is another similar problem that I developed that may be more
politically correct - and more relevant.
Headlights illuminate the road up to 160 ft in front of you. If you are on
a road with stop signs, what is the fastest speed you can drive and still
stop safely at night?
A typical reaction time for braking is 1.5 s (See Traffic Safety and the
Driver by Leonard Evans) and a typical braking acceleration for a car is 17
ft/s2.
Larry Woolf;General Atomics;6995 Flanders Dr.;MS 78-107;San Diego CA
92121-2975; Ph:858-526-8575;FAX:858-526-8568; www.ga.com; www.sci-ed-ga.org
-----Original Message-----
From: Tina Fanetti
Sent: Tuesday, September 24, 2002 10:31 AM
To: PHYS-L@lists.nau.edu
Subject: University Physics
Does anyone here use University Physics by Reese?
I am stuck on this problem, its multiple choice and I can get 3 of th=
e 5 choices :(
Here's the problem if anyone is interested....
Assume that the brakes of your car can slow it with an acceleration o=
f magnitude 6 m/s2. If Homer steps onto the road 50 m in front of yo=
ur car, what is the maximum speed you could be going in order to avoi=
d hitting Homer? Assume that it takes you 0.5 s to hit the brakes an=
d that you have constant acceleration during braking. =20