Motion at Constant Acceleration Question 3

Click For Summary

Homework Help Overview

The problem involves a car that slows down uniformly from a speed of 21.0 m/s to rest over a period of 6.00 seconds, with the goal of determining the distance traveled during this time.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the concept of average speed during uniform deceleration and question how to calculate it based on the given speeds and time.

Discussion Status

There is an ongoing exploration of the average speed and distance traveled, with some participants expressing confusion about the calculations and assumptions involved. Guidance has been offered regarding the relationship between initial and final speeds in uniformly accelerated motion.

Contextual Notes

Participants are grappling with the definitions of average speed and distance in the context of uniform acceleration, and there is uncertainty about the correct application of formulas related to motion.

Adrianna
Messages
13
Reaction score
0

Homework Statement


A car slows down uniformly from a speed of 21.0 m/s to rest in 6.00s. How far did it travel in that time?


Homework Equations



I am not really sure what one to use, which is the problem.

The Attempt at a Solution

 
Physics news on Phys.org
First, if it slows from 21 to 0 uniformly, what's the average speed at which the car travels within those 6 seconds? Then, what is the distance the car travels in 6 seconds at that average speed?
 
the average speed is 3.5 m/s it travels 21 m in 6 seconds right?
 
Is the average speed 3.5m/s?

Why would 21m/s divided by 6 give you the average speed?
 
Im not really sure I'm really confused... I thought that 21 was the distance and 6 was the time but I know that is wrong so isn't 21 m/s the average speed?
 
If the initial speed is 21 and the final speed is 0, and the deceleration is uniform, what do you think the average speed is? Just from intuition, the answer should be obvious, though the proof requires calculus.

For finding the average speed, disregard the fact that it took 6 seconds. How long it took to decelerate is unimportant. What is important is that the deceleration was constant.
 

Similar threads

Problem with the power of car
  • · Replies 3 ·
Replies
3
Views
1K
Relation between Friction, Velocity, and Acceleration
  • · Replies 16 ·
Replies
16
Views
2K
Help with question on motion: Avoiding a rear-end collision
  • · Replies 6 ·
Replies
6
Views
3K
Circular motion — the acceleration is not constant?
  • · Replies 1 ·
Replies
1
Views
2K
Non-Constant Acceleration Problem
  • · Replies 5 ·
Replies
5
Views
2K
Acceleration in uniform circular motion is uniform or non-uniform?
  • · Replies 55 ·
2
Replies
55
Views
3K
Motion of an Object: Displacement & Average Velocity
  • · Replies 8 ·
Replies
8
Views
2K
Which one of these motions is at constant acceleration?
  • · Replies 3 ·
Replies
3
Views
2K
Vertical circular motion
  • · Replies 8 ·
Replies
8
Views
2K
Circular motion/ speed increases at a constant rate
  • · Replies 7 ·
Replies
7
Views
2K