Bullet shot into pendulum - conservation of energy

In summary, the conversation discusses calculating the vertical and horizontal components of a pendulum's maximum displacement after a 27-g rifle bullet traveling 230m/s buries itself in a 3.3-kg pendulum hanging on a 2.9-m-long string. The proposed solution involves using the equation v= (m+M)/m * sqr root (2gh) and considering conservation of energy. The final goal is to find the height and distance on the x-axis.
  • #1
itryphysics
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0

Homework Statement


A 27-g rifle bullet traveling 230m/s buries itself in a 3.3-kg pendulum hanging on a 2.9-m-long string, which makes the pendulum swing upward in an arc.
Determine the vertical and horizontal components of the pendulum's maximum displacement.
x=? and h=?

Homework Equations


v= (m+M)/m * sqr root (2gh)


The Attempt at a Solution


I just expanded on the above equation and derived several others ..dont know where to go next.. L = length of string ; M=block's mass ; h=max height ; x=distance on x-axis ; m=bullet's mass
v= (m+M)/m * sqr root (2gh)
(v* (m/m+M)^2)/(2g)=h
h= L(1-cos theta)
cos-1 theta(-1 ((h/L)-1) = theta
L sin theta = x
EDIT: sorry nicksauce. I have now included the question.
 
Last edited:
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  • #2


What exactly is the question here? I see no question marks in your post.
 
  • #3


I would be inclined to use "conservation of Energy". You can calculate the kinetic energy of the bullet and you can take the potential energy to be 0 at the bottom of the arc. At the highest point the kinetic energy of both is 0 so all energy has be changed to potential energy. From the potential energy you can find the height.

I think this will get a better response in the physics section so I am going to move it there.
 

1. How does a bullet shot into a pendulum demonstrate conservation of energy?

When a bullet is shot into a pendulum, it gains kinetic energy. As the bullet collides with the pendulum, it transfers its kinetic energy to the pendulum, causing it to swing. However, the total amount of energy in the system (bullet + pendulum) remains constant, demonstrating the conservation of energy.

2. What factors affect the conservation of energy in a bullet-pendulum system?

The conservation of energy in a bullet-pendulum system is affected by factors such as the mass and velocity of the bullet, the length and weight of the pendulum, and the angle at which the bullet strikes the pendulum. These factors can impact the amount of kinetic and potential energy in the system.

3. How is the velocity of the bullet related to the swing of the pendulum?

The velocity of the bullet is directly related to the swing of the pendulum. The higher the velocity of the bullet, the more kinetic energy it has, and the more energy it will transfer to the pendulum upon impact. This will result in a larger swing of the pendulum.

4. Does the angle at which the bullet strikes the pendulum affect the conservation of energy?

Yes, the angle at which the bullet strikes the pendulum can affect the conservation of energy. A direct impact at a 90-degree angle will transfer the most amount of energy to the pendulum, while a glancing impact at an angle will transfer less energy and result in a smaller swing of the pendulum.

5. How does the conservation of energy apply to real-life situations?

The conservation of energy applies to many real-life situations, including bullet-pendulum systems. It is a fundamental law of physics that states energy cannot be created or destroyed, only transferred or transformed. This principle is essential in understanding and predicting the behavior of various physical systems, from simple pendulums to complex machines and processes.

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