### How JustAnswer Works:

• Ask an Expert
• Get a Professional Answer
• 100% Satisfaction Guarantee

## Ask The Geezer Your Own Question

The Geezer, Successful careers
Category: General
Satisfied Customers: 1387
Experience:  Retired Civil Engineer, USC Professor & Realtor, financier
2837397
Type Your Question Here...
The Geezer is online now

# how long would it take a tractot trailer

### Resolved Question:

how long would it take a tractot trailer combination weighing 80,000lbs to stop going down a 8% grade
Submitted: 7 years ago.
Category: General
Expert:  The Geezer replied 7 years ago.
The exact answer would depend on the condition of the unit's brakes, whether or not the pavement is dry, and whether or not there were any sand or gravel on the road.

You would also have to specify the speed at the time the brakes were applied.

But a reasonable estimate of the stopping distance, using a typical highway speeds, on FLAT ground, would be:

30 mph - 100 feet
60 mph - 426 feet
65 mph - 525 feet

http://www.truck-accident-lawfirm.com/CM/Resources/Trucking-Accidents-Collision.asp

From my Highway Engineering classes at USC many years ago, the increase in stopping distance for such a grade is in the range of 5-10%. This gives the following estimates:

30 mph - 110 feet
60 mph - 450 feet
65 mph - 575 feet

These estimates do NOT include the driver's reaction time, and assume that the brakes have not been overheated by immediately prior overuse.
The Geezer, Successful careers
Category: General
Satisfied Customers: 1387
Experience: Retired Civil Engineer, USC Professor & Realtor, financier
The Geezer and 45 other General Specialists are ready to help you

### JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

### What Customers are Saying:

• Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
< Last | Next >
• Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
• This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex Los Angeles, CA
• Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult. GP Hesperia, CA
• I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, NC
• Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around. Esther Woodstock, NY
• Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know. Robin Elkton, Maryland
• He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here. Diane Dallas, TX

• ### Ron

#### Satisfied Customers:

21772
23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs
< Last | Next >

### Ron

#### Satisfied Customers:

21772
23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs

### Dr. Y.

#### Satisfied Customers:

18773
I am fellowship trained specializing in general urology and reconstructive urology.

### John

#### Satisfied Customers:

13453
Appliance repair business owner for over 43 years.

### Tina

#### Satisfied Customers:

8681
JD, BBA Over 25 years legal and business experience.

### dermdoc19

#### Satisfied Customers:

3944
30 years practice in general and cosmetic dermatology

### Dr. Pat

#### Satisfied Customers:

3463
25+ years working primarily or exclusively with birds

### Dr. Gary

#### Satisfied Customers:

3421
DVM, Emergency Veterinarian, BS (Physiology)

## Related General Questions

Chat Now With An Expert
The Geezer
90 Satisfied Customers
Retired Civil Engineer, USC Professor & Realtor, financier