Measuring Projectile Velocity Using Block Deviation: A Guide

In summary, the conversation discusses a problem involving determining the velocity of a projectile that was shot into a block suspended on two ropes. The conservation of momentum and energy are mentioned as possible approaches to finding a solution, and the known values of the mass of the projectile, block, and length of the ropes are also mentioned.
  • #1
Gavroy
235
0
First of all: Sorry about my English, but I am from France ;-)
The problem:
Somebody shoots into a block which is put up on two free running ropes and now you want to determine the velocity of the projectile by measuring the deviation of the block. I also have to consider gravity, which may protect the block from being deviated and the projectile gets stuck to the block, if this is important.
I want to add that the mass of the projectile, the mass of the block and the length of the ropes are known.
I am sorry that I can’t offer you an initial stage for a solution. The only thing I know is that the conservation of momentum may be a possible approach
 
Physics news on Phys.org
  • #2
Welcome to PF!

Hi Gavroy! Welcome to PF! :smile:

In questions like this, divide the motion into two stages, the collision and the swing …

i] in the collision, momentum is conserved, so find the final velocity for the collision, wchi becomes the initial velocity for the swing

ii] in the swing, (mechanical) energy is conserved :wink:
 
  • #3
.

Bonjour! Tout d'abord, je tiens à vous remercier pour votre contribution et votre intérêt pour cette problématique. Votre idée d'utiliser la conservation de la quantité de mouvement est en effet une approche prometteuse pour mesurer la vitesse du projectile en utilisant la déviation du bloc. Cependant, il y a quelques points à prendre en compte pour obtenir une mesure précise.

Tout d'abord, il est important de noter que la gravité peut affecter la déviation du bloc. Il est donc essentiel de s'assurer que le bloc est suspendu de manière à minimiser l'influence de la gravité. Par exemple, en utilisant des cordes de longueurs égales et en plaçant le bloc au centre des cordes, vous pouvez réduire l'effet de la gravité sur la déviation.

Deuxièmement, il est également important de prendre en compte la masse du projectile et du bloc dans vos calculs. La conservation de la quantité de mouvement implique que la somme de la quantité de mouvement avant et après l'impact doit être égale. Vous devrez donc mesurer la masse du projectile et du bloc avec précision pour obtenir une mesure précise de la vitesse.

Enfin, il est possible que le projectile se colle au bloc après l'impact, ce qui peut affecter la déviation du bloc. Dans ce cas, il peut être utile d'utiliser un projectile avec une forme qui minimise les chances de coller au bloc, ou de mesurer la force nécessaire pour séparer le projectile du bloc après l'impact.

En résumé, votre approche de la conservation de la quantité de mouvement est un bon point de départ pour mesurer la vitesse du projectile en utilisant la déviation du bloc. Assurez-vous simplement de prendre en compte les facteurs mentionnés ci-dessus pour obtenir des résultats précis. Bonne chance dans vos expériences!
 

1. What is block deviation and how is it used to measure projectile velocity?

Block deviation is a method used to measure the velocity of a projectile. It involves placing a block of known mass in the path of the projectile and measuring the distance it travels after being hit. By knowing the mass of the block and the distance it travels, the velocity of the projectile can be calculated using the equation v = √(2*g*d/m), where v is the velocity, g is the acceleration due to gravity, d is the distance traveled by the block, and m is the mass of the block.

2. What are the advantages of using block deviation to measure projectile velocity?

Block deviation is a simple and cost-effective method for measuring projectile velocity. It does not require specialized equipment and can be easily performed in a controlled environment. Additionally, block deviation allows for multiple measurements to be taken and averaged, resulting in more accurate results.

3. Can block deviation be used to measure the velocity of any type of projectile?

Yes, block deviation can be used to measure the velocity of any type of projectile as long as the projectile is able to hit and move the block. This method has been used to measure the velocities of bullets, arrows, and even golf balls.

4. How accurate is block deviation in measuring projectile velocity?

The accuracy of block deviation depends on several factors, such as the precision of the measurements taken and the consistency of the projectile's trajectory. With proper technique and multiple measurements, block deviation can provide accurate results within a few percentage points of the actual velocity.

5. Are there any safety precautions that should be taken when using block deviation to measure projectile velocity?

Yes, safety precautions should always be taken when conducting any experiment involving projectiles. It is important to ensure that the area is clear of any obstructions or people, and to wear proper safety gear such as goggles and gloves. Additionally, the projectile should be launched at a safe distance and with caution to avoid any accidents.

Similar threads

  • Introductory Physics Homework Help
Replies
3
Views
387
  • Introductory Physics Homework Help
Replies
3
Views
911
  • Introductory Physics Homework Help
Replies
12
Views
1K
Replies
2
Views
2K
  • Introductory Physics Homework Help
Replies
16
Views
2K
Replies
27
Views
1K
  • Introductory Physics Homework Help
Replies
17
Views
4K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
10
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
1K
Back
Top