Problem on Mechanics (Newton's law of motion)

AI Thread Summary
The discussion centers on a student's interpretation of Newton's third law in the context of a head-on collision between a big lorry and a small car. The student correctly identifies that both vehicles experience equal and opposite forces during the collision, but questions arise regarding the injuries sustained by both drivers. It is noted that the larger mass of the lorry would likely push the lighter car backward, potentially causing more severe injuries to the car's driver. However, the discussion emphasizes that the different accelerations experienced by the drivers during the crash also contribute to the severity of injuries. Ultimately, the complexity of real-world collisions makes it challenging to predict outcomes based solely on Newton's laws.
Christy0721
Messages
3
Reaction score
0

Homework Statement


This question goes like this:
In an accident involving a big lorry and small car, the drivers of both vehicles were seriously injured. A student made a remark about the accident as follows: "A big lorry and a small car moved in the opposite directions and made a head-on collision. By Newton's third law of motion, the forces acting on both drivers are the same. As a result, both drivers were seriously injured."
Comment on the student's remark.

Homework Equations


[F][/net]=ma
Third law: Whenever an object A exerts a force on another object B, B exerts a force of equal magnitude and opposite direction on A at the same time.

The Attempt at a Solution


I think the student is correct. As the two vehicles collide head-on, they form an action-and-reaction pair. Therefore, both the lorry and the car receive the same magnitude of force exerted on them by each other.
What I'm not so sure about is which force caused the drivers' injury?
Is it because: the cars receive forces from opposite directions and this force causes the cars to stop abruptly, while the drivers still tend to move forward due to inertia. As a result, they hit the windscreens and get injured?
Like the teacher said this question is not that easy so I'm quite uncertain about my answer.
 
Physics news on Phys.org
Heavy lorry hits light car - imagine the situation and describe in words what you think would happen .
 
Nidum said:
Heavy lorry hits light car - imagine the situation and describe in words what you think would happen .
I think the lorry with a larger mass would drive the light car backwards during the collision and the passenger in the light car would be more seriously injured. But this won't explain why the driver in the lorry is also seriously injured.
 
Christy0721 said:
I think the lorry with a larger mass would drive the light car backwards during the collision and the passenger in the light car would be more seriously injured. But this won't explain why the driver in the lorry is also seriously injured.

In reality anything can happen as the result of a head on crash . Roughly speaking though the bigger and stronger the vehicle you are in relative to the one crashing into you the less injuries you are are likely to receive .

Christy0721 said:
"A big lorry and a small car moved in the opposite directions and made a head-on collision. By Newton's third law of motion, the forces acting on both drivers are the same. As a result, both drivers were seriously injured."

It's a nonsense question really but think about the different accelerations experienced by the two drivers during the crash .
 
I know right my teacher likes raising silly questions lol
Thanks anyways
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Trying to understand the logic behind adding vectors with an angle between them'
My initial calculation was to subtract V1 from V2 to show that from the perspective of the second aircraft the first one is -300km/h. So i checked with ChatGPT and it said I cant just subtract them because I have an angle between them. So I dont understand the reasoning of it. Like why should a velocity be dependent on an angle? I was thinking about how it would look like if the planes where parallel to each other, and then how it look like if one is turning away and I dont see it. Since...

Similar threads

Back
Top