Lifting height of a box in a truck going over a speed bump

[jamesdhurai]

Homework Statement

how to find lifting height

Relevant Equations

Any

hey guys need to know the way to find the solution to the problem.

Consider a truck which is traveled in a speed of 60km per hour.

A package weighs 50 kg is placed inside the truck with side supports to arrest the movement in x and y direction. But the top movement (z axis) is not arrested.

In this case, if the car moves over a speed breaker, how high the package will lift from its position?

 

[Lnewqban]

That height depends on the dimensions of the speed bump and on the capability of the truck's suspension to reduce the energy transferred to the package.

Not all speed bumps produce the same reaction.
Please, see:
https://en.wikipedia.org/wiki/Speed_bump#Comparison_to_speed_bumps

 

[berkeman]

Welcome to the PF.

Homework Statement:: how to find lifting height
Relevant Equations:: Any

hey guys need to know the way to find the solution to the problem.

Consider a truck which is traveled in a speed of 60km per hour.

A package weighs 50 kg is placed inside the truck with side supports to arrest the movement in x and y direction. But the top movement (z axis) is not arrested.

In this case, if the car moves over a speed breaker, how high the package will lift from its position?

We require you to show your own work on schoolwork problems before we can offer tutorial help. That said, as @Lnewqban points out, the height that the box will rise to depends on the height and shape of the speedbump, and the suspension of the truck. You must have been given more information in this problem, no?

 

[haruspex]

That height depends on the dimensions of the speed bump and on the capability of the truck's suspension to reduce the energy transferred to the package.

Not all speed bumps produce the same reaction.
Please, see:
https://en.wikipedia.org/wiki/Speed_bump#Comparison_to_speed_bumps

Sure, but it is possible to calculate an upper bound.

 

[Lnewqban]

Welcome, James
Sorry, I did not see it was your first post.
Could you show us the whole wording of the problem and your work so far?

 

[hmmm27]

Sure, but it is possible to calculate an upper bound.

"the distance between front bumper and the box" isn't really a calculation, more of an observation, from a safe distance.

(abject apologies to the OP if that's actually the textbook answer)

 

[haruspex]

"the distance between front bumper and the box" isn't really a calculation, more of an observation, from a safe distance.

(abject apologies to the OP if that's actually the textbook answer)

I was not referring to that (is that from the link you posted?). It is possible to calculate an upper bound from the info in the question.

 

[hmmm27]

I didn't post a link (that I recall): just one of the many vague uses for "" to indicate personal distancing from a saying.

I don't see how you could calculate an upper bound, given the incredible breadth of stick-figure physics.

(and I'd like to change my answer : using the front bumper to stop the rotation, the box could be flung into outer space, given enough ridiculous parameters for the "truck" and "speedbump")

 

[haruspex]

using the front bumper to stop the rotation, the box could be flung into outer space, given enough ridiculous parameters for the "truck" and "speedbump")

What vaguely reasonable mechanism would cause the box to rise faster than the max upward speed of the bed it rests on?

 

[hmmm27]

What vaguely reasonable mechanism would cause the box to rise faster than the max upward speed of the bed it rests on?

None that I can think of, offhand. Would you expect it to ?

 

[haruspex]

None that I can think of, offhand. Would you expect it to ?

No, which is why the jolt would not propel the box to a greater height than it could, in principle, raise the truck to. And that is limited by the KE of the truck.

In practice, the box does reach a greater height than the truck does because of the truck's suspension. But that is because the upward movement of the top of the truck is slowed as the suspension reaches relaxed position and the portion of mass below the suspension holds it back. Meanwhile, the box rises a little further under its acquired KE.

 

[hmmm27]

No, which is why the jolt would not propel the box to a greater height than it could, in principle, raise the truck to. And that is limited by the KE of the truck.

We seem to be talking at cross-purposes. Your question was concerning velocity, not height.

 

[haruspex]

We seem to be talking at cross-purposes. Your question was concerning velocity, not height.

The height the box reaches is determined by the vertical component of its launch velocity.