- #1

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter Fisica
- Start date

In summary: If so, what is the magnitude and direction of the force?In summary, the part of the pole that does not turn into angular momentum has momentum pointing in the original direction of the velocity.

- #1

Physics news on Phys.org

- #2

Simon Bridge

Science Advisor

Homework Helper

- 17,874

- 1,661

Please show us you best attempt at the problem in order that we know where you need the most help.

It would also help if there was a a translatable form of the question someplace.

- #3

Fisica

- 12

- 1

Ok, wait a minute.. i going to try to resolve and i will post a photo

- #4

Fisica

- 12

- 1

- #5

Simon Bridge

Science Advisor

Homework Helper

- 17,874

- 1,661

Yeah - I kinda get that it is a pole-vaulting exercize. "Salto Fosbury" translates into English as "Fosbury Flop".

In the model - a pole is set at an angle to the horizontal and travels left-to-right at some constant initial speed u.

When the bottom of the pole is in contact with the bottom of the wall, the horizontal motion stops and the pole rotates about the bottom end.

You've seen that this is a conservation of angular momentum problem - and you seem to have a handle on it.

The pole has length ##l##, mass ##m##, and initial velocity ##\vec v_i=u\hat\imath## (i.e. speed ##u## in the ##+x## direction.)

It has initial linear momentum was ##\vec p_i=mu\hat\imath## ... you follow so far?

Your question appears to be "what happens to this?"

Particularly, what happens to the part that does not turn into angular momentum?

Consider:

The part that turns into angular momentum is the component of the initial momentum that is perpendicular to the pole. ##p_\perp = mu\sin\theta##

... that's the*magnitude* - but momentum is a vector.

So what is the momentum that is left over?

Which direction does it point in? (A sketch will be enough to see.)

Consider also: Is the pole acted on by a force during the vault?

In the model - a pole is set at an angle to the horizontal and travels left-to-right at some constant initial speed u.

When the bottom of the pole is in contact with the bottom of the wall, the horizontal motion stops and the pole rotates about the bottom end.

You've seen that this is a conservation of angular momentum problem - and you seem to have a handle on it.

The pole has length ##l##, mass ##m##, and initial velocity ##\vec v_i=u\hat\imath## (i.e. speed ##u## in the ##+x## direction.)

It has initial linear momentum was ##\vec p_i=mu\hat\imath## ... you follow so far?

Your question appears to be "what happens to this?"

Particularly, what happens to the part that does not turn into angular momentum?

Consider:

The part that turns into angular momentum is the component of the initial momentum that is perpendicular to the pole. ##p_\perp = mu\sin\theta##

... that's the

So what is the momentum that is left over?

Which direction does it point in? (A sketch will be enough to see.)

Consider also: Is the pole acted on by a force during the vault?

Last edited:

Angular momentum is a physical quantity that represents the rotational motion of an object. It is defined as the product of an object's moment of inertia and its angular velocity. In simpler terms, it is the measure of how fast an object is rotating and how much mass is concentrated away from its axis of rotation.

According to the law of conservation of angular momentum, the total angular momentum of a system remains constant unless acted upon by an external torque. This means that in a closed system, the sum of initial angular momentum equals the sum of final angular momentum.

A collision is an event where two or more objects come into contact with each other, resulting in a change in their motion. Collisions can be elastic, where there is no loss of kinetic energy, or inelastic, where some kinetic energy is lost due to deformation or friction.

The law of conservation of momentum states that the total momentum of a closed system remains constant. In a collision, the total momentum of the system before the collision is equal to the total momentum after the collision, regardless of whether the collision is elastic or inelastic.

The law of conservation of energy states that energy cannot be created or destroyed, only transferred from one form to another. In collisions, the total energy of the system remains constant, but it may change from kinetic energy to other forms of energy, such as heat or sound, depending on the type of collision.

- Replies
- 4

- Views
- 690

- Replies
- 4

- Views
- 1K

- Replies
- 1

- Views
- 1K

- Replies
- 6

- Views
- 3K

- Replies
- 1

- Views
- 1K

- Replies
- 3

- Views
- 2K

- Replies
- 17

- Views
- 511

- Replies
- 8

- Views
- 1K

- Replies
- 16

- Views
- 2K

- Replies
- 1

- Views
- 2K

Share: