Calculate the initial velocity given degree and time

Click For Summary
SUMMARY

The discussion focuses on calculating the initial velocity of an object launched at a 70-degree angle that lands after 6.5 seconds. The user initially attempted to apply the equation Range = v0²sin(2θ)/g but expressed uncertainty about its applicability in this scenario. The conversation highlights the importance of breaking down the motion into x and y components, specifically emphasizing the y component affected by gravitational acceleration (g). The user is encouraged to utilize the equation Voy = s * Cos(θ) * t - 0.5gt² for further calculations.

PREREQUISITES
  • Understanding of projectile motion principles
  • Familiarity with trigonometric functions in physics
  • Knowledge of gravitational acceleration (g)
  • Ability to manipulate equations involving time, angle, and velocity
NEXT STEPS
  • Study the derivation and application of projectile motion equations
  • Learn how to decompose vectors into x and y components
  • Explore the concept of gravitational acceleration and its effects on motion
  • Practice solving problems involving initial velocity and launch angles
USEFUL FOR

Students studying physics, particularly those focusing on kinematics and projectile motion, as well as educators seeking to clarify concepts related to initial velocity calculations.

://Justice
Messages
27
Reaction score
0

Homework Statement


haha, so hopefully my last question for the night!
Find the initial velocity, when the object is shot at 70 degrees and took 6.5s to land. (hint: look at the y direction first this time)
(For more information regarding my question, visit my earlier question from tonight: https://www.physicsforums.com/showthread.php?p=2890328#post2890328)


Homework Equations


So, I doubt it will work, but there is the equation I used earlier, Range = v02sin2θ/g



The Attempt at a Solution


Now, I know that there is the method of dividing it up into components of x and y, however I did not quite understand that. When calculating the initial velocity, given distance traveled and degree, I used Range = v02sin2θ/g which worked great (refer to https://www.physicsforums.com/showthr...28#post2890328 ), however, I don't know if that can apply to this too... Sorry, but physics is really confusing me at the minute

Let me try the component method... Okay, so, looking at the y component. Y is affected by g. Voy=s*Cos(theta)*t -.5gt^2. (I don't know if that equation is correct). So, than, I don't know s... stuck... Sure I did something wrong or I am just not getting something...
 
Last edited by a moderator:
Physics news on Phys.org
*Bump*
I really need help with this tonight...
 

Similar threads

Projectile motion, initial height and range given, find initial velocity
  • · Replies 8 ·
Replies
8
Views
2K
projectile motion problem with no initial velocity given
  • · Replies 3 ·
Replies
3
Views
1K
Solving for Time Given Acceleration & Initial Velocity
  • · Replies 3 ·
Replies
3
Views
1K
Projectile Motion Problem Involving Initial Velocity and Gravity Only
  • · Replies 11 ·
Replies
11
Views
2K
The final velocity = initial velocity + acceleration x time
  • · Replies 17 ·
Replies
17
Views
2K
Initial velocity given time and angle
  • · Replies 8 ·
Replies
8
Views
2K
Initial velocity of bird landing on horizontal wire modeled as spring
  • · Replies 7 ·
Replies
7
Views
1K
A ball is thrown w/initial speed vi at an angle 𝜃i with the horizontal
  • · Replies 5 ·
Replies
5
Views
2K
Projectile Motion: initial velocity problem
  • · Replies 1 ·
Replies
1
Views
2K
How to find initial velocity with only an angle and distance?
  • · Replies 2 ·
Replies
2
Views
2K