A ball is shot from the ground into the air and horizontal distance

AI Thread Summary
A ball is shot from the ground, reaching a height of 9.7 m with a velocity of 7.4 m/s horizontally and 5.1 m/s vertically. The discussion focuses on calculating the total horizontal distance traveled and the velocity just before impact, including its j-component. Kinematic equations for projectile motion are introduced, emphasizing the need to identify known and unknown variables. The equations x(t)=v_{0x}t and y(t)=v_{0y}t - (gt^2)/2 are relevant for solving the problem, assuming no air resistance. Understanding the relationship between velocity, position, and acceleration is crucial for determining the initial velocity and the ball's trajectory.
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1. The problem statement, all variables and given/known da
A ball is shot from the ground into the air. At a height of 9.7 m, the velocity is observed to be
v = (7.4)i + (5.1)j in meters per second (i horizontal, j upward).

Homework Equations


What will be the total horizontal distance traveled by the ball?
What is the velocity of the ball (magnitude and direction) the instant before it hits the ground? What is its j-component?

The Attempt at a Solution


I have no idea please help!
 
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Are you familiar with the kinematic equations for projectile motion?
 
yes please explain.
 
The basic equations of motion for a projectile with no air resistance are:
x(t)=v_{0x}t
y(t)=v_{0y}t-\frac{gt^2}{2}
This assumes the projectile starts from (0,0), which is hinted at in the problem. Here, v_{0x} is the x-component of initial velocity, and v_{0y} is the y-component of initial velocity.

Now, what are your knowns and unknowns? Before you can use these equations to find the "wants", you need to solve for some of the values of the equations. (Hint: you'll need another equation that relates velocity, position, and acceleration to find the initial velocity. Also, take into account the fact that in the x direction there is no acceleration, so what happens to the x velocity over time?)
 
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