Vector Kinematics: Vertical Acceleration of a Skier on a 30.0 Degree Hill

  • Thread starter Thread starter homeworkboy
  • Start date Start date
  • Tags Tags
    Kinematics Vector
Click For Summary

Homework Help Overview

The discussion revolves around a physics problem involving vector kinematics, specifically focusing on the vertical acceleration of a skier descending a 30.0 degree hill and the time taken to reach the bottom from a height of 375 m.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants explore how to break down the skier's acceleration into vertical and horizontal components using trigonometric functions. There are questions about the applicability of trigonometry in this context and the correct equations to use for solving the problem.

Discussion Status

Some participants have provided guidance on using trigonometric functions to find the vertical component of acceleration and suggested relevant kinematic equations. There appears to be a mix of understanding and confusion regarding the application of these concepts, with some participants questioning their approach.

Contextual Notes

Participants are working under the constraints of a homework assignment, which may limit the information they can use or the methods they can apply. There is also a mention of a separate problem involving projectile motion, indicating a broader context of vector analysis in physics.

homeworkboy
Messages
35
Reaction score
0
A skier is accelerating down a 30.0 degree hill at 1.80 m/s2.

What is the vertical component of her acceleration?

How long will it take her to reach the bottom of the hill, assuming she starts from rest and accelerates uniformly, if the elevation change is 375 m
 
Last edited:
Physics news on Phys.org
What effort have you made to solve this problem?
 
I don't even understand how it should be approached
 
Draw a picture of what's going on. X and y axes and a vector from the origin going 30 degrees from the horizontal downward. Then break it into its component vectors. The one pointing down is your vertical acceleration
 
To find the vertical or horizontal component of any vector is simple trig. To break a vector into components, you usually use the formulas

Vy = VSin(a)
Vx = VCos(a)

Where a is the angle from the horizontal and V is any given vector.

Once you have the vertical component of acceleration, you're ready to solve using kinematics.

You have the acceleration, the height of the hill, and the initial velocity is 0. Which equation could you use to solve for time?
 
Oh ok...i thought that trigonometry of vectors only applies when we are dealing with velocity..sorry..thanks i got the sum...i then used the second eq of motion...
X=volt + 1/2at2
 
homeworkboy said:
Oh ok...i thought that trigonometry of vectors only applies when we are dealing with velocity..sorry..thanks i got the sum...i then used the second eq of motion...
X=volt + 1/2at2

Nope... Force vectors are the most common in your course. You can use vectors to describe velocity, but be sure not to mix them into your free-body diagrams.
 
i got another one

A baseball is hit with a speed of 27.0 m/s at an angle of 49.0 degrees. It lands on the flat roof of a 14.0 m tall nearby building.If the ball was hit when it was 1.4 m above the
ground, what horizontal distance does it travel before it lands on the building?
 
i found the time using t = 2Voy/g which came out to be 4.2 seconds...and then wat do i do??
 

Similar threads

Replies
7
Views
2K
Replies
3
Views
3K
Replies
10
Views
3K
  • · Replies 7 ·
Replies
7
Views
4K
  • · Replies 13 ·
Replies
13
Views
7K
  • · Replies 3 ·
Replies
3
Views
1K
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 6 ·
Replies
6
Views
1K