# Kinematics Projective Motion Problem

• physics7889
In summary, the problem involves calculating the speed of a fly ball hit by Joe Carter during spring training. The ball cleared a 10m fence and the given information includes the 45 degree angle of the tangent formed, the distance from the fence to the landing point of the projectile, and the gravitational acceleration. By using the equation vyf^2 = vyi^2 + 2*g*h, where vyi is the same as vx, which was found to be 12.5 m/s, the final velocity can be calculated.

#### physics7889

Projectile Motion

## Homework Statement

Joe Carter hit a fly ball during spring training. It just cleared a 10m fence, Calculate the speed of the ball when it leaves his bat at ground level. Ignore friction.
http://img155.imageshack.us/img155/7161/physics.png [Broken]

## The Attempt at a Solution

v in x direction was found to equal 12.5 m/s which is the same as v in y direction since the tangent formed was a 45-45-90 degree angle triangle.

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You need to show your work, along with relevant equations. Also, what is the 8 m? Is that the distance from the batter to the wall, or the distance from the landing spot to the wall?

its the distance from the fence to the landing point of the projectile

Is the 45 degree angle given to you, or something you solved for?

It was given to me, this is really all the information that was given

Well it looks like your attempt at the solution is right so far. But it is recommended you show your work, so it doesn't look like you just copied the answer from somewhere.

Also, what do you know about the velocity in the x-direction since the only acceleration is the gravitational acceleration in the y-direction.

When the ball reaches the ground, vx remains the same.
vyf^2 = vyi^2 + 2*g*h.
vyi is the same as vx, which you have found. h is given. Find vyf.
Initial velocity v = sqrt(vyf^2 + vx^2)

## What is "Kinematics Projective Motion Problem"?

"Kinematics Projective Motion Problem" is a physics concept that involves the study of motion of objects in a two-dimensional plane, taking into account factors such as velocity, acceleration, and angle of projection. It is commonly used to analyze the trajectory and motion of projectiles, such as a ball being thrown or a bullet being fired from a gun.

## What is the difference between projectile motion and regular motion?

Projectile motion is a specific type of motion in which an object is launched into the air and follows a curved path due to the force of gravity. Regular motion, on the other hand, refers to the motion of an object that is not affected by external forces and moves in a straight line at a constant speed.

## How is projectile motion calculated?

Projectile motion is typically calculated using the equations of motion, which take into account the initial velocity, angle of projection, and acceleration due to gravity. These equations can be used to determine the maximum height, range, and time of flight for a projectile.

## What are some real-life examples of projectile motion?

Some common real-life examples of projectile motion include a baseball being thrown, a basketball being shot into a hoop, and a cannonball being fired from a cannon. These objects all follow a curved path due to the force of gravity.

## How does air resistance affect projectile motion?

Air resistance, also known as drag, can affect the trajectory of a projectile by slowing it down and altering its path. This is why objects with a larger surface area, such as a feather, will experience more air resistance and have a different trajectory compared to objects with a smaller surface area, such as a bullet.