Speed bump question - Newton's laws

Click For Summary

Homework Help Overview

The discussion revolves around the physics of motion as it relates to driving over a speed bump, specifically through the lens of Newton's laws. Participants explore the forces experienced by a driver when transitioning over a bump shaped like an arc of a circle.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the concept of inertia and how it relates to the feeling of being lifted from the seat. There are questions regarding the forces acting on the driver, particularly the normal force exerted by the seat and how it changes during circular motion.

Discussion Status

The conversation is active with participants questioning the nature of forces during circular motion and the implications for the normal force. Some guidance has been offered regarding the relationship between weight and the forces experienced while going over the bump, but no consensus has been reached on the exact calculations or outcomes.

Contextual Notes

Participants are working within the constraints of a homework problem that requires them to apply Newton's laws and consider the effects of circular motion on forces. There is an emphasis on understanding the physical concepts rather than simply calculating a numerical answer.

feveroffate
Messages
8
Reaction score
0
1.
You're driving down the road at 8 m/s and go over a speed bump. When you go over the bump, you feel lifted from your seat. Explain why.

I assumed it was because of inertia, but I'm not sure.

You weigh 700 N. If it is approximated that the speed bump is shaped like an arc of a circle, with radius of 10 m, find the magnitude of force the seats exerts on you as you go over the speed bump.

If F = mv^2/r, then would you just plug everything in directly?
 
Physics news on Phys.org
The seat normally pushes upward on you with 700 N (because you push down on it with 700 N weight). While in circular motion, though, you experience a centrifugal force upward that reduces the 700 N.
 
So while in circular motion, you aren't pushing down on the seat with 700 N so you are lifted up?
 
It is unlikely you will float up off the seat - that would take a terrific speed - but the force pressing you against the springs of the seat will be reduced so the spring compression will be less and you will go up a little bit.
 
But would the seat still exert 700 N upward? I mean, would I just plug in the numbers into the equation for the second part?
 
700 - mv^2/r
 

Similar threads

Some homework questions in astrophysics (Kepler's Laws, Newton's Laws)
  • · Replies 6 ·
Replies
6
Views
2K
Understanding the Minimum Speed to Keep Carriage on Tracks in a Loop
  • · Replies 5 ·
Replies
5
Views
2K
Understanding Newton's First Law & Safety Measures for Roller Coaster Rides
  • · Replies 4 ·
Replies
4
Views
4K
Circular Motion - Newton's Laws in different reference frames
  • · Replies 4 ·
Replies
4
Views
2K
Torque lost using Newton's law of viscosity
  • · Replies 2 ·
Replies
2
Views
2K
Given speed/mass find R (centripetal)
  • · Replies 1 ·
Replies
1
Views
1K
Need help on Newton's Law Question and Determining speed
  • · Replies 1 ·
Replies
1
Views
2K
Normal Force - Car over a Circular Arc
  • · Replies 4 ·
Replies
4
Views
6K
Airplane pilot in a dive, net force, minimum speed, and normal force.
  • · Replies 5 ·
Replies
5
Views
3K
Faraday's law and linearly time dependent B field
  • · Replies 3 ·
Replies
3
Views
1K