Work/force/kinematics slingshot problem

  • Thread starter Thread starter Shadowsol
  • Start date Start date
  • Tags Tags
    Slingshot
Click For Summary

Homework Help Overview

The discussion revolves around a problem involving work, force, and kinematics related to a slingshot launching a rock from a height. Participants are exploring the application of the spring/work equation and the conversion of potential energy to kinetic energy in this context.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss whether the spring/work equation applies to the slingshot scenario and if the distance stretched corresponds to the variable in the equation. There are questions about how to derive the velocity of the rock after being shot and the role of gravitational acceleration in the calculations.

Discussion Status

Some participants have provided guidance on the relationship between potential energy and kinetic energy, indicating that the spring potential energy converts to kinetic energy. Others have confirmed the approach of using kinematics to find time and velocity, but there is no explicit consensus on the correctness of all steps taken.

Contextual Notes

Participants are working within the constraints of a homework problem, which may limit the information available for discussion. There are assumptions about the final velocity and the application of equations that remain under examination.

Shadowsol
Messages
22
Reaction score
0
1. An average force of 8.2 Newtons is used to pull a .4 kg rock, stretching a sling shot 43 centimeters. The rock is shot downward from a bridge 18 meters above a stream. What will be the velocity of the rock just before it hits the water? How much time will it take to hit the water.



Homework Equations





3. I just want to know if the spring/work equation, .5k(x)squared=w applies to the slingshot, and would stretching it by 43 CM = the x part of the equation? I don't know what to do once I get work. How do i get the velocity of the rock? I know A after shot would be 9.8, d is 18, but is final Velocity 0?
 
Physics news on Phys.org
Shadowsol said:
3. I just want to know if the spring/work equation, .5k(x)squared=w applies to the slingshot, and would stretching it by 43 CM = the x part of the equation? I don't know what to do once I get work. How do i get the velocity of the rock? I know A after shot would be 9.8, d is 18, but is final Velocity 0?


It does apply, and yes. The spring PE is converted to KE. That's how you get the velocity. Final velocity nowhere is zero.
 
Ok, so I put in the force*the distance it was pulled back to get the potential sling shot energy. I than set that equal to the KE equation and got V. Than I simply used that V as V0, used 9.8 as A, and 18 m as D, than solved for V1. Is this correct?
 
Absolutely. You find the time using the same kinematics.
 

Similar threads

Solving Slingshot Problem Homework
  • · Replies 5 ·
Replies
5
Views
4K
What is the work done on a slingshot?
  • · Replies 3 ·
Replies
3
Views
2K
Questioning the Solution for Elevator vs Rock Problem
  • · Replies 7 ·
Replies
7
Views
2K
Find the Force applied to a rock by a slingshot
  • · Replies 3 ·
Replies
3
Views
5K
Calculating Elastic Force and Projectile Motion: Energy/Work Questions
  • · Replies 5 ·
Replies
5
Views
2K
How do I find the final velocity and how high the bridge is?
  • · Replies 2 ·
Replies
2
Views
2K
Displacement of mass fired by a slingshot problem
  • · Replies 4 ·
Replies
4
Views
3K
Calculating velocity in a slingshot
  • · Replies 2 ·
Replies
2
Views
22K
Can You Calculate the Splash Radius of a Rock Dropped from a Bridge?
  • · Replies 6 ·
Replies
6
Views
2K
Energy in spring (slingshot problems)
  • · Replies 4 ·
Replies
4
Views
4K