Help Kinematics in 2d Question

In summary, the conversation discusses a problem involving kinematics in 2D, where the velocity vector of water at the top of Niagara Falls needs to be calculated. The conversation mentions using the angle and x velocity component to form an equation and solve for the final vertical velocity. Then, the vertical displacement can be found using a formula involving the vertical velocity and gravity. However, despite this help, the person asking the question still got the answer wrong.
  • #1
Morokana
7
0
Help! Kinematics in 2d Question!

Suppose the water at the top of Niagara Falls has a horizontal speed of 1.23 m/s just before it cascades over the edge of the falls. At what vertical distance below the edge does the velocity vector of the water point downward at a 49.4 degrees angle below the horizontal?
 
Physics news on Phys.org
  • #2
The angle is given as 49.4degrees...
And you know that tan of an angle will be y/x, and you're given the x velocity component, 1.23m/s...
Now, you can form an equation...
tan 49.4 = Vy/1.23
Solve it for Vy... (Vy is that final vertical velocity)
Then, to find the vertical displacement, use the formula (Vy)^2 = u^2 + 2gy given Vy, g and u. (It's a waterfall... so vertical velocity is assumably initially 0m/s)
Solve it for y. :}
 
  • #3
Oh..

Hey thanks for your help man ... BUT ... i got it wrong ..andi failed ..
 

1. How do you calculate the position of an object in 2D kinematics?

The position of an object in 2D kinematics is calculated using the equations: x = x0 + v0x * t + 1/2 * ax * t^2 and y = y0 + v0y * t + 1/2 * ay * t^2, where x and y are the final position coordinates, x0 and y0 are the initial position coordinates, v0x and v0y are the initial velocities in the x and y directions, and ax and ay are the accelerations in the x and y directions.

2. What is the difference between speed and velocity in 2D kinematics?

Speed is the magnitude of velocity, while velocity is a vector quantity that includes both the magnitude and direction of an object's motion in 2D kinematics.

3. How is acceleration calculated in 2D kinematics?

Acceleration in 2D kinematics is calculated using the equation: a = (vf - vi) / t, where a is the acceleration, vf is the final velocity, vi is the initial velocity, and t is the time interval.

4. What is the difference between average and instantaneous velocity in 2D kinematics?

Average velocity is the total displacement of an object divided by the total time taken, while instantaneous velocity is the velocity of an object at a specific moment in time in 2D kinematics.

5. How does the direction of motion affect an object's trajectory in 2D kinematics?

The direction of motion affects an object's trajectory in 2D kinematics by determining the angle at which the object will move and the shape of its path. An object with a constant velocity will have a linear trajectory, while an object with a changing velocity or acceleration will have a curved trajectory.

Similar threads

  • Introductory Physics Homework Help
Replies
2
Views
861
  • Introductory Physics Homework Help
Replies
20
Views
8K
  • Introductory Physics Homework Help
2
Replies
38
Views
1K
  • Introductory Physics Homework Help
Replies
6
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
14K
  • Introductory Physics Homework Help
Replies
7
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
Back
Top