Acceleration on a hill (both up and down)

  • Thread starter Thread starter BATBLady
  • Start date Start date
  • Tags Tags
    Acceleration Hill
Click For Summary

Homework Help Overview

The problem involves a sports car accelerating up and down a hill inclined at 16.0° with a given coefficient of static friction. The original poster seeks to determine the maximum acceleration in both scenarios, highlighting a lack of clarity in their approach.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the need to find the net force acting on the car and apply Newton's second law. There is a focus on whether the mass of the car is necessary for the calculations, with some suggesting to treat mass as a variable.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the problem. Some guidance has been offered regarding solving symbolically rather than numerically, but no consensus has been reached on the correct approach or calculations.

Contextual Notes

There is a mention of missing information regarding the mass of the car, which is causing uncertainty in the calculations. The original poster expresses confusion about how to proceed without this information.

BATBLady
Messages
17
Reaction score
0

Homework Statement


A sports car is accelerating up a hill that rises 16.0° above the horizontal. The coefficient of static friction between the wheels and the road is µs = 0.87. It is the static frictional force that propels the car forward.
(a) What is the magnitude of the maximum acceleration that the car can have?
(b) What is the magnitude of the maximum acceleration if the car is being driven down the hill?

Homework Equations


FN=ma=mgcos\theta
fs=FN\mus


The Attempt at a Solution



Attached is the pic I've been using to figure this out. I'm somewhat lost at how to proceed though.
 

Attachments

Physics news on Phys.org
Find the net force acting on the car. Apply Newton's 2nd law.
 
I've been trying to do that. I know I'm trying to find acceleration, thus the equations I'm working with should be the ones I gave. However, I need the mass for both of those and I'm not given it (at least that's where my line of thought is).
 
BATBLady said:
However, I need the mass for both of those...
Maybe you do, maybe you don't. :wink: Just call the mass "m" and keep going.

Hint: Solve for the acceleration symbolically before plugging in any numbers.
 
The way I've figured it, it'd be:

9.8cos16/8.7=a=10.82 m/s2

I put the answer in the system and it doesn't work out. Where am I going wrong?
 
Do it step by step. What's the force acting up the hill? Down the hill? What's the net force?
 

Similar threads

Worksheet Problem about Power (average power of a car accelerating up a hill)
  • · Replies 2 ·
Replies
2
Views
2K
What is the deceleration of a snowboarder going up a 5.0° slope?
  • · Replies 2 ·
Replies
2
Views
13K
What are the forces acting on a child pulling a wagon up an inclined hill?
  • · Replies 3 ·
Replies
3
Views
5K
Car on a hill - reasoning for static friction
  • · Replies 5 ·
Replies
5
Views
7K
Maximum speed of car on downhill
  • · Replies 1 ·
Replies
1
Views
2K
Sledding Down a Hill - Speed Calculation
  • · Replies 5 ·
Replies
5
Views
3K
Why Does a Car Accelerate When Rolling Down a Hill?
  • · Replies 11 ·
Replies
11
Views
3K
Speed skier travelling up a hill
  • · Replies 7 ·
Replies
7
Views
4K
How do I draw a free body diagram of a car on a slope?
  • · Replies 4 ·
Replies
4
Views
6K
Inclined plane in a circular motion
  • · Replies 17 ·
Replies
17
Views
3K