Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
LABORATORY 4: BALLISTIC PENDULUM Introduction In this experiment you will use the ballistic pendulum to study an inelastic collision. This device is a simplified version of equipment used to measure the muzzle velocity of a rifle. In the rifle experiment, a bullet is fired into a wooden block suspended on ropes. The bullet becomes embedded in the block, and the block swings upward like a pendulum. This is an example of a perfectly inelastic collision : the bullet and block stick together after the collision. The muzzle velocity can be determined by analyzing the subsequent motion of the block and embedded bullet. ************************** SAFETY ISSUES **************************** * * * 1. Wear safety goggles during this experiment. * * 2. Students with long hair should tie it back, so it will not get caught in * * the spring gun. * * 3. Load the gun by pushing on the bullet with your palm, while holding * * the apparatus steady with your other hand. * * 4. Do not fire your gun into the pathway where other students may walk. * * 5. Do not accidentally walk into the path of another group’s firing. * * * * NEVER POINT THE GUN AT ANYONE! * * YOU WILL BE BANISHED FROM THE LAB * * IF YOU THREATEN ANYONE. * * * ************************************************************************* INVESTIGATION 1: Determining the initial velocity of the bullet Equipment The equipment to be used is shown in Fig. 1. A spring-loaded “gun” (#1) fires a steel or brass “bullet” (#2) with an initial velocity . The bullet is trapped by a cup (#3), which is suspended on an arm (#4) to form a pendulum. The cup is initially at rest, but after the collision the pendulum begins to swing upward. A ratchet (#5) at the bottom of the cup is captured at the highest point of swing by the toothed track (#6). o v 1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Figure 1 – The ballistic pendulum apparatus with the bullet in the firing position. The pendulum cup (#3) is in position to receive the bullet. Theory The spring gun is fired so the bullet (mass m ) is captured by the cup (mass M ) at the bottom of the pendulum. The gun gives the bullet a certain initial horizontal velocity . Since the drag of the air is negligible, the horizontal velocity of the bullet is still when it strikes the cup. The capture of the bullet occurs so rapidly there is no time during the collision for the pendulum to rise at all. The cup with the captured bullet moves with a new horizontal velocity V just after the collision.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/03/2008 for the course PHYSICS 11 taught by Professor Rogertobin during the Summer '06 term at Tufts.

Page1 / 8


This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online