Impulse problem: how can these two angles be different?

• kostoglotov
In summary, the conversation discusses the relationship between impulse and momentum in the context of a baseball bat hitting a baseball. The answer is that the bat gives the ball an impulse of 12 kg m s-1 to the left at an angle of 15 degrees above the horizontal, which may seem counter-intuitive but can be explained mathematically. Impulse is related to momentum as it is the change in momentum and can be affected by the initial momentum of an object. The conversation also explores the concept of a "triangle of forces" and how it relates to the angle at which the ball leaves the bat.
kostoglotov

Homework Statement

A baseball weighing 140g is traveling to the right at 35 m/s, makes contact with a baseball bat, and then leaves the bat at 55 m/s to the left at an angle 25 degrees from the horizontal.

I got the right answer, I how how the solution works mathematically.

The answer is that the bat gave the ball an impulse of 12 kg m s-1 to the left at an angle of 15 degrees above the horizontal...

This seems sooo counter-intuitive to me. How can the impulse be at a different angle from the final velocity vector that the ball got from interacting with the bat? Shouldn't they be the same angle?

Again, I know how it works mathematically, trigonometrically...I just don't get what is happening here in a physical sense.

kostoglotov said:

Homework Statement

A baseball weighing 140g is traveling to the right at 35 m/s, makes contact with a baseball bat, and then leaves the bat at 55 m/s to the left at an angle 25 degrees from the horizontal.

I got the right answer, I how how the solution works mathematically.

The answer is that the bat gave the ball an impulse of 12 kg m s-1 to the left at an angle of 15 degrees above the horizontal...

This seems sooo counter-intuitive to me. How can the impulse be at a different angle from the final velocity vector that the ball got from interacting with the bat? Shouldn't they be the same angle?

Again, I know how it works mathematically, trigonometrically...I just don't get what is happening here in a physical sense.
What is the relationship between impulse and momentum ?

SammyS said:
How is impulse related to momentum ?

It's the change in momentum...I'm thinking now that the ball should leave at the same angle only if the ball were stationary. Given that the ball already had some horizontal momentum, the new "triangle of forces" created by the impact has a shorter horizontal component relative to it's vertical component if we were comparing it to the stationary ball case...so...the baseball bat is absorbing some of the horizontal momentum of the ball, giving some of it back, but not all of it, and also giving it some vertical momentum, and because the bat isn't returning all of the balls horizontal momentum, it can leave at a different angle to the impulse given.

1. What is the impulse problem?

The impulse problem is a problem in physics that involves determining the change in momentum of an object when a force is applied over a certain period of time. It is also known as the impulse-momentum theorem.

2. How can two angles be different in the impulse problem?

In the impulse problem, the angles refer to the direction of the force applied to the object. If the force is applied at two different angles, the resulting change in momentum will also have different directions, resulting in different angles.

3. Is the impulse problem related to collisions?

Yes, the impulse problem is often used to analyze collisions between objects. In a collision, the force applied to an object causes a change in its momentum, and the impulse problem helps to determine this change.

4. What is the equation for the impulse problem?

The equation for the impulse problem is I = F * t, where I is the impulse (change in momentum), F is the force applied, and t is the time period over which the force is applied.

5. How is the impulse problem used in real-life situations?

The impulse problem is used in various real-life situations, such as analyzing the impact of a car crash, calculating the force needed to stop a moving object, and understanding the movement of projectiles. It is also used in sports, such as calculating the force of a soccer player's kick or determining the speed of a baseball pitch.

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