Question about the inertia of logs in a pickup truck that stops suddenly

In summary: Yes, I missed your post 5. In summary, if the logs fall off the truck and become lighter, this might cause the truck to accelerate. However, this would most likely injure the passenger as he would be crushed between the truck and the logs.
  • #1
ellieee
78
6
Homework Statement
would my answer be accepted? the suggested answer is:
the wood logs would become loose
when the vehicle suddenly stops, the wood logs will still be moving forward due to inertia and will hit the passenger
Relevant Equations
nil
CamScanner 07-17-2021 13.56_2.jpg
CamScanner 07-17-2021 13.56.jpg
 
Last edited by a moderator:
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  • #2
I would not accept it since, while it is a possibly true statement, it CLEARLY is not what the question is looking for.
 
  • #3
... but they are not even true statements.
There is no reason why the logs should fall off in any direction except sideways, and if falling off in that direction, no reason they would push the truck forward. How would they exert a forward force on the truck?
There is no reason to suppose the truck and passenger were accelerating forward before the truck came to a sudden halt, nor any reason to suggest the passenger would accelerate forward as a result. The passenger may continue forward at the same velocity for a little, but what has that to do with the logs?
 
  • #4
I think the passenger will be injured because of both the reasons. He is crushed between the logs and truck.
(I believe that in such questions we are to ignore friction between the logs and floor of truck)
 
  • #5
haruspex said:
and if falling off in that direction, no reason they would push the truck forward.
but assuming they fall off, then the truck will become lighter, and assuming the driver doesn't slow down, won't the truck accelerate?
 
  • #6
Shreya said:
I think the passenger will be injured because of both the reasons. He is crushed between the logs and truck.
Neither explanation offered in post #1 leads to the passenger being crushed by the logs. If anything , they argue for the passenger gaining more space to stand in.
 
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  • #7
IMG_20210717_151335.jpg

The logs move forward due to inertia , only to hit the man and since he is trapped in there and can't fly off, he gets severely injured
 
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  • #8
haruspex said:
r being crushed by the logs. If anything , they argue for the passenger gaining more space to stand
I don't think the logs move backwards?
 
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  • #9
Shreya said:
View attachment 286125
The logs move forward due to inertia , only to hit the man and since he is trapped in there and can't fly off, he gets severely injured
Please do not answer the question for the student. The approach of these homework forums is to nudge the student towards arriving at the answer.
 
  • #10
haruspex said:
Please do not answer the question for the student. The approach of these homework forums is to nudge the student towards arriving at the answer.
Sure, won't do.
 
  • #11
Shreya said:
I don't think the logs move backwards?
I did not suggest they they do.
The first explanation offered in post #1 has the truck accelerating forwards. The second has the passenger accelerating away from the logs.
 
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  • #12
haruspex said:
I did not suggest they they do.
The first explanation offered in post #1 has the truck accelerating forwards. The second has the passenger accelerating away from the logs.
hello, did u miss my post 5?
 
  • #13
ellieee said:
but assuming they fall off, then the truck will become lighter, and assuming the driver doesn't slow down, won't the truck accelerate?
If the truck was moving at a steady speed then the engine was working hard enough to overcome rolling resistance and drag, but no more. The logs falling off would reduce rolling resistance a touch but not much change to drag. So it might accelerate a little. But what if it does? How would that injure the passenger?
 
  • Informative
Likes Shreya

1. What is inertia?

Inertia is the resistance of an object to change its state of motion. It is a property of matter that causes objects to stay at rest or in motion unless acted upon by an external force.

2. How does inertia apply to logs in a pickup truck that stops suddenly?

When a pickup truck suddenly stops, the logs inside the truck will continue to move forward due to their inertia. This means that they will resist the change in motion and may even fly off the truck if not secured properly.

3. Why is it important to consider the inertia of logs in a pickup truck?

Considering the inertia of logs in a pickup truck is important for safety reasons. If the logs are not properly secured, they can cause damage to the truck or potentially harm other drivers on the road if they fly off the truck.

4. How can the inertia of logs in a pickup truck be reduced?

The inertia of logs in a pickup truck can be reduced by securing them properly. This can be done by using tie-down straps or ropes to keep the logs in place and prevent them from moving around when the truck stops suddenly.

5. Can the inertia of logs in a pickup truck be used to the driver's advantage?

Yes, the inertia of logs in a pickup truck can be used to the driver's advantage. If the logs are properly secured, they can help distribute the weight of the truck and improve its stability while driving. However, it is important to note that the driver should still be cautious and not rely solely on the inertia of the logs for stability.

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