Finding the x component of position vector

Click For Summary
SUMMARY

The discussion focuses on calculating the x component of a position vector for a ball influenced by both gravitational and electric forces. The initial vertical velocity is 16.55 m/s, and the gravitational acceleration is -9.8 m/s². The user initially calculated the time of flight as 3.377 seconds but obtained an incorrect x position of 18.84 m instead of the correct 31.13 m. The error stems from neglecting the acceleration due to the electric field, which is quantified as 2.148 m/s², necessitating a revision of the kinematic equations to include this acceleration.

PREREQUISITES
  • Understanding of kinematic equations in physics
  • Knowledge of forces and acceleration, specifically in the context of electric fields
  • Ability to calculate time of flight for projectile motion
  • Familiarity with unit notation and conversions in physics
NEXT STEPS
  • Revise kinematic equations to incorporate constant acceleration due to electric fields
  • Learn about the effects of electric fields on charged particles
  • Study projectile motion with multiple forces acting on an object
  • Explore the relationship between force, mass, and acceleration in detail
USEFUL FOR

Students and educators in physics, particularly those studying mechanics and electromagnetism, as well as anyone involved in solving problems related to projectile motion under the influence of multiple forces.

hraghav
Messages
48
Reaction score
5
Homework Statement
A ball of mass 𝑚=4.07kg is thrown over level ground in a region where the electric field is 𝐸⃗=5.5N/C𝑖̂. The ball has a charge 𝑞=1.59C. The ball was thrown from the origin with an initial velocity of 𝑣⃗𝑖=5.58m/s𝑖̂+16.55m/s𝑘̂. Gravity provides an acceleration of 𝑔⃗=−9.8m/s^2𝑘̂. What is the x-component of the position vector where the ball lands?
Relevant Equations
t = 3.377s
x = 18.84m which is wrong
I first calculated the time using y = (viy)(t) + 0.5gt^2 where y is the vertical displacement which is 0 for the ball landing back on the ground, viy is the initial vertical velocity ie 16.55m/s and g = -9.8m/s}^2. I get 2 values for t, t=0 and t= 3.377s. Then using the equation x = (vix)(t) = (5.58m/s)(3.377s) I get x as 18.84m. The correct answer is 31.13m and I am not sure where I am going wrong.
Could someone please help me with this and let me know where am I making an error?
Thank you
 
Physics news on Phys.org
hraghav said:
Could someone please help me with this and let me know where am I making an error?
You are ignoring the force exerted by the electric field on the charged ball. What is that force? What acceleration does it provide? Rewrite the kinematic equations to reflect this correction.
 
  • Like
Likes   Reactions: MatinSAR
kuruman said:
You are ignoring the force exerted by the electric field on the charged ball. What is that force? What acceleration does it provide? Rewrite the kinematic equations to reflect this correction.
F = qE = 8.745 and acceleration = F/m = 2.148 but how do I use these values in my question?
 
hraghav said:
F = qE = 8.745 and acceleration = F/m = 2.148 but how do I use these values in my question?
You have assumed that the ball is not accelerating in the x-direction in your solution. This tells you that it does have a constant acceleration that you must incorporate. You have already handled one case of constant acceleration in this problem so doing it again should be relatively straightforward.

Note: Never ever write numbers without appropriate units.
 
  • Like
Likes   Reactions: MatinSAR and PeroK

Similar threads

  • · Replies 6 ·
Replies
6
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
8
Views
1K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 16 ·
Replies
16
Views
2K
  • · Replies 38 ·
2
Replies
38
Views
4K
Replies
5
Views
4K
Replies
5
Views
1K
Replies
12
Views
1K