Bullet & Pendulum Homework: Determine Horiz. Displacement

In summary, a 16.2 g rifle bullet traveling at 240 m/s collides with a 3.54 kg pendulum hanging from a 2.90 m string, causing the pendulum to swing upward in an arc. To determine the horizontal component of the pendulum's displacement, conservation of energy and momentum must be used, along with trigonometry. The interaction can be divided into two stages: the collision of the bullet and pendulum, and the rise of the pendulum and bullet after the collision. In each stage, different quantities are conserved, such as kinetic energy and potential energy.
  • #1
BMWPower06
92
0

Homework Statement


An 16.2 g rifle bullet traveling 240 m/s buries itself in a 3.54 kg pendulum hanging on a 2.90 m long string, which makes the pendulum swing upward in an arc. Determine the horizontal component of the pendulum's displacement.


Homework Equations



I used the Y center of mass equation which is:
Ycm= m1y1+m2y2/m1+m2 but i got 2.9


The Attempt at a Solution


Im stuck and don't know what else to do
 
Physics news on Phys.org
  • #2
use conservation of (total) energy and momentum. Neglect the heat that the bullet will "create" when hitting the pendelum. You must use some trigometry also.
 
  • #3
Consider the interaction as having two stages:
(1) The collision of bullet and pendulum--what's conserved?
(2) The rise of the pendulum+bullet (post collision)--what's conserved?
 
  • #4
Doc Al said:
Consider the interaction as having two stages:
(1) The collision of bullet and pendulum--what's conserved?
(2) The rise of the pendulum+bullet (post collision)--what's conserved?

so i find the PE+KE=PE+KE for both parts

or in other words

.5MV2=mgh for both parts?
 
  • #5
Yes.

First the energy is the kinetic energy of bullet. Then all energy will be potential energy of the pendelum and the bullet. (m1+m2)gh
 
  • #6
BMWPower06 said:
so i find the PE+KE=PE+KE for both parts

or in other words

.5MV2=mgh for both parts?
Not exactly. Different quantities are conserved in each part of the motion. For example: During the collision, mechanical energy is not conserved. What is?
 

1. What is a bullet and pendulum experiment?

A bullet and pendulum experiment involves studying the horizontal displacement of a bullet fired at a suspended pendulum. The experiment aims to determine the horizontal distance traveled by the bullet before it hits the pendulum.

2. How is the horizontal displacement of a bullet calculated in this experiment?

The horizontal displacement is calculated by measuring the distance between the starting point of the bullet and the point at which it hits the pendulum. This distance is known as the horizontal displacement.

3. What factors can affect the horizontal displacement of a bullet in this experiment?

The horizontal displacement of a bullet can be affected by several factors such as the initial velocity of the bullet, the mass of the bullet, the angle at which it is fired, and any external forces acting on the bullet.

4. How is the horizontal displacement related to the velocity of the bullet in this experiment?

The horizontal displacement is directly proportional to the velocity of the bullet. This means that as the velocity of the bullet increases, the horizontal displacement also increases.

5. What is the significance of determining the horizontal displacement in this experiment?

Determining the horizontal displacement allows us to calculate the accuracy and precision of the bullet's trajectory. It also helps in understanding the effects of different factors on the bullet's flight and can be used to improve shooting techniques and ballistics calculations.

Similar threads

  • Introductory Physics Homework Help
Replies
7
Views
5K
  • Introductory Physics Homework Help
Replies
2
Views
3K
  • Introductory Physics Homework Help
Replies
2
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
3K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
6
Views
4K
  • Introductory Physics Homework Help
Replies
7
Views
3K
  • Introductory Physics Homework Help
Replies
5
Views
3K
  • Introductory Physics Homework Help
Replies
16
Views
2K
  • Introductory Physics Homework Help
Replies
5
Views
11K
Back
Top