Bullet Definition and 650 Threads

Homework Statement A bullet of mass m and charge q is fired towards a solid uniformly charged sphere of radius R and total charge + q. If it strikes the surface of sphere with speed u, find the minimum speed u so that it can penetrate through the sphere. (Neglect all resistance forces or...

If F=ma, why does a bullet that's going a constant velocity, have enough force to penetrate an object?

Homework Statement A 3.50kg block of wood is at rest on a 1.75-m high fencepost. When a 12.0g bullet is fired horizontally into the block, the block topples off the post and lands 1.25m away. What was the speed of the bullet immediately before the collision?The attempt at a solution d=1/2at^2...

A 15-g bullet is fired from a rifle. It takes 2.5 × 10^-3 s for the bullet to travel the length of the barrel, and it exits the barrel with a speed of 715 m/s . Assuming that the acceleration of the bullet is constant, find the average net force exerted on the bullet Answer : 4290 N I need...

This paper appears to further the case for DM vs MOND http://arxiv.org/abs/1401.3162, A simple model linking galaxy and dark matter evolution.

I'm hoping that someone on this board can tell me where I'm going wrong here. Basically, I'm trying to calculate the upward angle at which one would need to aim a gun in order to fire a bullet to perfectly compensate for the effect of gravity on the bullet during the course of its flight over a...

What is the theoretical max velocity for a gunpowder fired bullet that we use today in all guns and artillery? What is the MAIN limiting/deciding factor? I'm guessing it would be the gunpowder burn speed/pressure increase right? Now what about theoretical max velocity for...

Hi, I'm sure this topic has come up before, however, it was always under the requirements of being realistic, i.e. taking drag, air resistance, Earth rotation and what not into account. Also, I couldn't find any equations so that I can do the math myself. Hence, here is my question...

Angular Velocity After Bullet Hits Cylinder Homework Statement A 11.0g bullet is fired at 378.1m/s into a solid disk of mass 19.1kg and a radius 0.250m. The disk is initially at rest and is mounted on fixed vertical axis that runs through it's center of mass. The line of motion of the...

Homework Statement Me and a friend of mine have been sitting around in a sleep deprived state unable to think properly pondering a problem I don't think either of us have the capacity to solve (we're freshmen, alright, we just started learning differential equations.) I forget how I started...

Homework Statement There's a stationary block (m1=1,5kg) in a table (Coefficient of Friction=0,4). A bullet passes through the block and hits a person. The block moved 1,2m. Calculate the velocity of the bullet (mb=0,0079kg and vib=709,88m/s) when it hit the person. Homework Equations...

Homework Statement A 6.20g bullet traveling at 485m/s embeds itself in a 1.73kg wooden block at rest on a frictionless surface. The block is attached to a spring with k = 79.0N/m A)Find the Period B)Find the Amplitude C)Find the totla energy of the bullet+block+spring system before the...

I'm stuck in in school suspension and I have to finish this quiz (it's open note/technology, not cheating!) by the end of school today, and I can't seem to find a problem similar to this on the internet, so I'm coming here. If you want like, I dunno, a poem or a drawing or something, I'll give...

1. I have to create an exercise to calculate the velocity of a block of wood (m=1,5 kg). A bullet passed through a block that was on a table also made of wood. What I really want to calculate is the initial velocity of the bullet, but, in order to do that, I need to know the velocity of the...

Homework Statement A bullet of mass m strikes an amor plate with initial velocity v0. As the bullet burrows into the plate, its motion is impeded by a frictional force which is directly proportional to the bullet's velocity. There are no other forces acting on the bullet. -Use Newton's Second...

Is it possible to calculate the force caused by a bullet in a bone, knowing the velocity of the bullet when fired, its weight, and the bone's thickness? If so, could you explain it a bit? I need to create a sort of exercise, so I wanted to do something involving a bullet and a body. Therefore...

Homework Statement bullet shot horizontally over level ground with a velocity of 300m/s. at the instant that the bullet leaves the barrel, its empty shell casing falls vertically and strikes the ground with a vertical velocity of 5.00m/s how far does the bullet travel what is the vertical...

Homework Statement A 15 g bullet is fired into a 2.55 kg block that is hanging by a 2.0 m long string. The speed of the bullet is 425 m/s. Calculate the angle when the system reaches its maximum height?Homework Equations m1v1=(m1+m2)vf (1/2)mv^2=mghThe Attempt at a Solution (0.015 kg)(425...

1. A 3.0-g bullet traveling at a speed of 400 m/s enters a tree and exits the other side with a speed of 200 m/s. Where did the bullet's lost KE go, and what was the energy transferred? 2. ΔKE+ΔPE+ΔU = Q-W 3. The only questions I have about this problem are why does the Work=0, Heat=0, and why...

Homework Statement Agent Arlene devised the following method of measuring the muzzle velocity of a rifle (the figure below). She fires a bullet into a 4.064-kg wooden block resting on a smooth surface, and attached to a spring of spring constant k = 164.5N/m . The bullet, whose mass is 7.870...

Homework Statement A 7.00 g bullet, when fired from a gun into a 1.10 kg block of wood held in a vise, penetrates the block to a depth of 6.40 cm. This block of wood is next placed on a frictionless horizontal surface, and a second 7.00 g bullet is fired from the gun into the block. To what...

I was thinking about force lately, after reading some physics 100 questions on the internet to see if I have what it takes to become a physicist. For example, when you shoot a bullet, the chemical reaction that takes places exerts a force on the bullet for a short period of time (due to...

Homework Statement A bullet of mass m and speed v passes completely through a pendulum bob of mass M. The bullet emerges on the other side of the pendulum bob with half its original speed. Assume that the pendulum bob is suspended by a stiff rod of length L and negligible mass. What is the...

Homework Statement A rocket of rest length 100 meters is moving at .6c relative to Earth and contains an astronaut at the tail end of the ship. The astronaut fires a bullet toward the front of the ship. The velocity of the bullet relative to the astronaut is 0.8c. How much time does it take the...

I'm kind of confused by this: Suppose a rifle is zeroed in at 800 meters (the bullet hits the line of sight at 800m). This means the bullet must be fired at an upwards angle, the scope stays pointing directly at 800 meters. Crude diagram, line of sight = blue, barrel direction = red...

I was thinking of a couple basic mechanics problems lately. What if you have a rod sitting in space at rest, and you shoot a bullet at its center. Linear momentum is conserved, and the problem is quite trivial. Now what if the bullet hit the rod slightly off of the rod's CG? I think linear...

Let's say that an object is 3 inches thick, how dense would it have to be to stop a bullet traveling 680 mp/h?

This question is about this video on YouTube, in which a bullet is fired vertically into the center of a wooden block from below, sending the block up into the air. Next, a bullet is fired vertically but off-center into a similar block from below, again causing the block to rise into the air...

A friend of mine asked me this question out of curiosity: If you shoot a bullet straight up into the air, how far would the bullet land from the point it went up? Possible factors: - Earth's rotation - air resistance What is the answer?

Homework Statement A 2.25g bullet embeds itsself in a 1.50kg block, which is attached to a spring of force constant 785N/m. If the max compression of the spring is 5.88cm, find the initial speed of the bullet and the time for the bullet block system to come to rest. The speed comes out to...

Hello All, Homework Statement I was at the firing range the other day when the gun instructor mentioned that the bullet of a AR-15 rifle can travel 5 - 6 miles depending on the angle of the gun when the bullet leaves the muzzle. I wanted to confirm this for myself so, I tried to find the...

My friend and I are working on a realistic FPS sniper simulator and we wanted to be able to realistically model things like bullet drop, flight time, and impact energy. I've managed to find the drag coefficients for different rounds and I know the exit velocity, so now I want to use that to...

A sniper fires a bullet at 120 m/s at 30° above the horizontal from the roof top of a 35 m high parking garage. If the bullet strikes the level ground beside the parking garage: a.)How long was the bullet in the air? b.)How far from the base of the parking garage did the bullet land? c.)At...

Homework Statement There is a small block of steel with mass 2.4kg and is firmly attached to a low mass wheel a distance .3m from its center. The wheel is free to rotate about a vertical axis and is at rest. A .0023kg bullet traveling with an initial speed of 305m/s in the horizontal plane...

Homework Statement A uniform rod of length L rests on a frictionless horizontal surface. The rod pivots about a fixed frictionless axis at one end. The rod is initially at rest. A bullet traveling parallel to the horizontal surface and perpendicular to the rod with speed v strikes the rod at...

Homework Statement A 10.0-g bullet traveling at 200 m/s strikes a fixed wooden block. The bullet comes to rest 22 cm inside the block. The magnitude of the force exerted on the bullet by the block over its 22-cm travel is shown in graph. Find the value of Fmax...

I had asked a question on the effect Recoil has on a bullet's trajectory and got wonderful help from this site. Thank you! Now I have another question... I used to think rain had no effect on a bullet until I realized I wasn't actually hitting any raindrops, when I started hitting them, I...

1.So the problem given is the following, "A small wooden block with mass 0.775 kg is suspended from the lower end of a light cord that is 1.58m long. The block is initially at rest. A bullet with mass 0.0134 kg is fired at the block with a horizontal velocity v0. The bullet strikes the block...

Homework Statement A rifle is aimed horizontally at a target 30m away. The bullet hits the target 1.9cm below the aiming point. what are the bullets time of flight and the initial velocity? Homework Equations ax=0 g=9.8m/s^2 x0=0m xf=30m y0=0m yf=.019m v0x=? vfx=0m/s v0y=0 vfy=0...

Homework Statement A ballistic pendulum is used to measure the speed of a bullet fired from a gun. The pendulum consists of a 20.0g block hanging from a string. A bullet, with mass 0.50gg, imbeds itself in the block causing the block to swing up to a height of 5.00cm. Find the speed of the...

Homework Statement A hunter on the ground aims his gun directly at a monkey hanging from a high tree branch some distance away. At the instant the gun is shot the monkey drops from the branch, hoping to avoid the bullet. Show analytically that the monkey made the wrong move. Ignore air...

Hi! I was watching Discovery channel the other day and it was showing a series on evolution of guns and ammo.. It showed that earlier there was bolt mechanism for firing the gun. And then, a revolution came when muzzzle or bullet was shot such that it went in forward direction while...

1. A 0.0048kg pullet traveling with a speed of 200m/s penetrates a large wooden fence post. If the average resisting force exerted on the bullet was 4500N how far did the bullet penetrate. 2. F=ma? 3. F = ma F/m = a 4500/0.0048 = 937500? So there's a reverse acceleration of...

Back in World War Two, the Russians developed an experimental weapon called so eloquently "Fire Hedgehog" that fired 88 ppsh submachine guns straight down as a volume strafing device. Knowing quite a bit about straight line ballistics, i was curious to know more about the effectiveness of this...

After watching a fascinating youtube video demonstrating the Lenz Effect using a 1.5T MRI machine and an aluminum block, I was wondering if it would stop a bullet fired along the axis of the machine. If so, would there be any defensive military application?

Homework Statement A bullet of mass 12.0 grams is traveling with a speed V0 and strikes a block of mass M = 1.00 kg that rests on a horizontal surface (mu = 0.40). After the bullet imbeds in the block, it slides 2.60 meters before coming to rest. The initial velocity of the bullet must have...

I have an idea that I would like to discuss. My idea is to emit a low pressure low friction gas out the nose of a small arms bullet. I believe it would lower the drag over the body of the bullet thus increasing velocity and range. I just need to know if the phyics are right is this...

Homework Statement A bullet is shot vertically into the air at a speed of 512 m/s. a) to what maximum height does the bullet go? b) how much time passes before the bullet stops rising? c) what is the velocity of the bullet after 60s? Homework Equations a) V2²=V1²+2ad b) a=...

I been looking on google and getting help from several people who are trying to help me, but I just can't understand this. It is to advance for me as of now and I need a example to help show me. But I need this for homework so can someone help and provide formula explaining how this would. Be...

Homework Statement A gangster fires a bullet (m1 = 30 g, v1 = 190 m/s) at Stupendous Man (m2 = 31 kg), but it simply bounces away elastically. If Stupendous man was standing on a frictionless surface, what is the change in speed of the bullet after striking stupendous man? Be careful with...