Bullet Definition and 644 Threads

In the Bullet Cluster, we have two well defined galaxy clusters that exhibit gravity lensing. Between them is a mass of gas (mostly hydrogen and helium) that is roughly eight to nine times the stellar (observable) mass of the two galaxies. The mass of gas doesn't exhibit any lensing. My question...

I have a bullet with a initial velocity and an apple in free fall (-9.8 acceleration). Whenever I shoot the bullet it will hit the apple as long as the vector of the bullet is aimed at the apple. What I want to know is why does that occur? Why is it that as long as I aim the apple, the bullet...

I've read a lot of opinions and a lot of published pieces about the Bullet Cluster. Please correct me if I'm wrong, but the Bullet Cluster doesn’t prove ΛCDM (it has far too much collision velocity for such a model) so much as as it disproves MOND. The argument seems to be: MOND can describe...

Homework Statement A ball of mass M and radius R can rotate round an axis through it's center. a bullet of mass m travels with speed v, hits the ball near the surface and gets stuck in it. What's their angular velocity after the collision. Homework Equations Moment of inertia of a ball round...

When a bullet from a rifle hits a small wall, the wall falls apart. According to Newton's third law of motion, the wall should also exert an equal and opposite force as exerted by the bullet. The wall should be able to withstand the force exerted by the bullet on it. Why doesn't this happen?

< Mentor Note -- OP has been reminded to use the HH Template and show their work in future posts... >[/color] A man fires a bullet into a swimming pool. There is a distance of 6m from the gun to the bottom of the pool. Does the bullet have enough force through the water to break an average...

My brother actually said this and felt that it would not effect the person's hand. He said, theoretically, if a person were to move their hand from the side of the bullet (so as to slap the bullet) , at the same speed as the bullet, the bullet would would change its direction and the hand would...

Homework Statement In the figure here, a 12.8 g bullet moving directly upward at 930 m/s strikes and passes through the center of mass of a 8.3 kg block initially at rest. The bullet emerges from the block moving directly upward at 520 m/s. To what maximum height does the block then rise above...

1. A distant camera is taking an image of a bullet of proper length l_0 and velocity v. The bullet is moving on a straight line which is parallel to the ruler (a bit behind the bullet, when it is watched from the camera). An angle between the velocity vector and the line that connects the camera...

Can anyone tell me what is the air resistance on the top of a bullet train when it is moving at top speed

The venturi effect of the new ARX bullet almost doubles side exit velocity. What happens if the exit velocity exceeds the sound barrier in a fluid like a gelatin block?

Homework Statement A bullet of mass 2.0 * 10-3 kg is fired horizontally into a free-standing block of wood of mass 4.98 * 10-1 kg, which it knocks forward with an initial speed of 1.2 m s-1. (a) Estimate the speed of the bullet. (b) How much kinetic energy is lost in the impact? (c) What...

Homework Statement A bullet is shot vertically into the air at a speed of 512 m/s. 1) To what maximum height does the bullet go? 2) How much time passes before the bullet stops rising? 3) What is the velocity of the bullet after 60.0 s?[/B]Homework Equations 1) V2²=V1²+2ad 2) a= (V2-V1)/Δt...

I was on a firearms forum and a guy said something along the lines of this. When you're handloading your own cartridges, if you use a mild powder load (less powder) in a handgun versus a hot load (more powder), you would think that shifts the point of impact of the bullet on the target lower...

Homework Statement A rifleman is shooting at a target at a firing range. The rifle has a mass of 4.0kg. When the gun's trigger is pulled, a bullet of mass of 10g will exit the rifle's barrel at a speed of 800m/s. The rifle is stationary at the instant the trigger is pulled. Given that the rifle...

Homework Statement Which equation could adequately be used to determine how high the block goes after being hit by the bullet (a height h)? (see figure) (m+M)gh+ksh=1/2(m+M)V^2 (m+M)gh+1/2ksh^2=1/2(m+M)V^2 (m+M)v+ksh=(m+M)V Homework Equations KE=1/2mv^2 Ugrav=Mgh PE of spring = 1/2ks(s^2...

I am a student, and a few days ago in physics class we were discussing about the 'bullet fired from a train scenario', where e.g. if a train is heading towards a certain direction at 200 km/h and a bullet is fired at 800 km/h, the bullet would travel at 1000 km/h relative to the ground. However...

Homework Statement A bullet fired straight upwards experiences an acceleration due to air resistance of 1m/s2 during its entire flight. If it leaves the barrel of the gun at 300m/s, with what speed does it hit the ground? Homework Equations None given The Attempt at a Solution integral of a=t...

So this problem was a 2 part question. The first part goes as such. 1. A gun is fired straight up. Assuming that the air drag on the bullet varies quadratically with speed, show that the speed varies with height according to the equations: v2 = Ae-2kx - (g/k) (upward motion) v2 = (g/k) -...

Let say a plane flights at 1km/s, shoots a 2kg projectile at 1km/s, so to the Earth, the projectile flights at 2km/s with 2*2*2/2 = 4MJ. The same gun when fixed on Earth, shoots the same 2kg projectile at 1km/s, achieves 2*1*1/2 = 1MJ Assume that the energy comes from burning propellant or...

I am solving some problems of my physics book for fun and for some reason I am getting a wrong answer from this one. 1. Homework Statement A bullet is shot at an angle of 35o with a speed of 90 m/s. I assume that air resistance is ignored. Calculate bullet's distance from launch site 2,5...

If a gun fires a bullet at a velocity v and is then taken aboard a plane traveling at a velocity v and is fired again in the direction of travel ,what is the simplest proof that the bullet's new velocity is now 2v ?

Hey guys apparently the answer to this is 491 m/s, but i keep getting 34m/s by using a method whereby i find out the height reached by the block then using kinetic energy to potential energy... doesn't seem to work tho! Please help! A 50.0 g bullet is fired into a stationary 10.0 kg block...

(like the wavefront that is photographed when it travels through air)

a bullet travels at 340m/s , my weight is 70kg , the weight of the bullet is 5g , let's assume that the bullet hits me and neater me or the bullet take damage , the speed loss of the bullet is zero , and here is my question : how many meters will the bullet push me back in this case ? sorry for...

(Mentor's Note: Thread moved from general physics after being replied to, hence the lack of a template) Find the momentum of a 50g bullet whose kinetic energy is 250J. I know the formula to find momentum is P= mv. Please give me hints

So, I'm currently writing a mathematical analysis of a bullet with a muzzle velocity of 790 m/s. I have found that the standard equation for drag force... Fd = 1/2 * ρ * v2 * Cd * A does not work because the drag coefficient for a bullet (.295) does not account for supersonic speeds. What I...

Homework Statement A 6.64-g bullet is moving horizontally with a velocity of +340 m/s, where the sign + indicates that it is moving to the right. The bullet is approaching two blocks resting on a horizontal frictionless surface. Air resistance is negligible. The bullet passes completely through...

Homework Statement A wooden block of mass M resting on a frictionless, horizontal surface is attached to a rigid rod of length l and of negligible mass. The rod is pivoted at the other end. A bullet of mass m traveling parallel to the horizontal surface and perpendicular to the rod with speed v...

In this clip the mythbusters are investigating projectile motion at a firing range: Using the fact that the bullet fell approximately 1 inch as it traveled 100 feet, I predicted it should travel 600 feet down the firing range before hitting the ground from a height of 36 inches. Instead, it...

Homework Statement A bullet has a mass of 7.5 g. It is fired into a ballistic pendulum. The pendulum's receiving block of wood is 2.5 kg. After the collision, the pendulum swings to a height of 0.1 m. What is the approximate velocity of the bullet? m_{bullet} = 7.5g = 0.0075 kg m_{wood} = 2.5...

This problem was given verbally during a class period, so I will set it up in my own words. A bullet (.012kg) is fired at a block (.800kg) hanging on a strong, massless string of length 1.6m. After the collision the bullet is embedded in the block. When the block is .8m above its original...

Homework Statement A riffle barrel and a laser point directly towards a target some distance away. General relativity says that the bullet and the light experience the same downward acceleration during horizontal travel, yet the bullet hits the target well below the laser beam. Explain...

Homework Statement Hello, first year engineering student here :)https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/v/t35.0-12/10744040_871781156179440_107104578_o.jpg?oh=73c4261941e7ef6b7c682558c0925a63&oe=544F5CA4&__gda__=1414428985_0415c28b8b2e194bf0b57f065267fe49 [/B] The question is...

Homework Statement A 0.031 kg bullet is fired from a shotgun of mass 3.63kg at 420 m/s. If the collision of the recoiling gun with your shoulder takes 0.013s, what is the average force the gun exerts against your shoulder? Homework Equations p = m • v[/B] vf=vi + at F=ma The Attempt at a...

Homework Statement A lead bullet flies at 350[m/s], hits and stops. if no heat escapes, how much will it's temperature rise Homework Equations ##Q[cal]=m\cdot c\cdot \Delta t## Specific heat of lead: c=0.031 1[cal]=4.186[Joule] The Attempt at a Solution The kinetic energy...

Question: A bullet is fired horizontally aiming at an object which starts falling at the instant the bullet is fired. Show that the bullet will hit the object. Problem: The conventional way students are advised to address this question is to consider that all limits are bounded: the...

Hi everyone. I'm quite troubled with this physics question. A .035 kg bullet is fired from a .23 m barrel. The bullet experiences a force of 4500 N while in the gun barrel. What is the kinetic energy of the bullet as it leaves the gun barrel? I don't understand how to figure out the...

Homework Statement At the instant a horizontally held rifle is fired over a level range, a bullet held at the side of the rifle is released and drops to the ground. Which bullet, the one fired downrange or the one dropped from rest, strikes the ground first? Homework Equations None The...

Homework Statement Imagine that a bullet is shot vertically into the air with an initial speed of 9800 m/s. If we ignore air friction, how high will it go? vi = 9800 m/s h = ? Homework Equations v2 = vi2 + 2aΔy Ki = Ui --> 1/2mv2 = mgh F = (Gm1m2)/r The Attempt at a...

Three blocks (1,2,3) of mass 3.00 kg, 2.00 kg, 1.00 kg sit linearly 10.0 cm apart from each other on a frictionless surface. A 25 g bullet is shot at the first block, it travels through the first block, and embeds itself into the second block (without falling over) which then collides into...

Homework Statement A 7-g bullet is fired into a 1.5-kg ballistic pendulum. The bullet emerges from the block with a speed of 200 m/s, and the block rises to a maximum height of 12 cm. Find the initial speed of the bullet.Homework Equations conservation of momentumThe Attempt at a Solution First...

The bullet cluster remains controversial, as evidenced today by http://arxiv.org/abs/1404.5633 and http://arxiv.org/abs/1404.5636. I'm puzzled by the motivation for this kind of dissent. I view this as a desperate attempt by alternative model advocates to preserve their own views.

Homework Statement A block A of mass MA = 1 kg is kept on a smooth horizontal surface and attached by a light thread to another block B of mass MB=2 kg .Block B is resting on ground and thread and pulley are massless and frictionless.A bullet of mass m 0.25 kg moving horizontally with velocity...

Hello, This is not really homework, but is in the context of my course. We always say that a bullet embeded into a wood does not conserve energy. We say heat is created. But, I was wondering: is the deformation of the wood considered heat released or is it some other kind of energy? Is...

Homework Statement Homework Equations The Attempt at a Solution Angular momentum is the only parameter conserved. This is because there are no external torques acting on the system. Energy is not conserved because the collision is inelastic. Finally, linear momentum is not...

A 10g bullet with v = 1000 m/s strikes a 100g block which is at rest. What is their combined velocity? Can this be done with conservation of energy? momemtum? Here we have inelastic collision so by conservation of momentum \[ 10\cdot 1000 + 0 = 110\cdot v_f\Rightarrow v_f =...

Homework Statement A bullet of mass 4.2 g strikes a ballistic pendulum of mass 2.0 kg. The center of mass of the pendulum rises a vertical distance of 18 cm. Assuming that the bullet remains embedded in the pendulum, calculate the bullet's initial speed. Homework Equations The...

Homework Statement An Earth satellite is revolving in a circular orbit of radius 'a' with velocity 'v0'. A gun is in the satellite and is aimed directly towards the earth.A bullet is fired from the gun with muzzle velocity v0/2.Neglecting resistance offered by cosmic dust and recoil of...

Homework Statement A bullet weighing m = 50g with a initial speed of v = 300m/s hits a wall. The wall is build in a way that the value of the force it causes on the bullet is given by: . The time starts after the bullet hits the wall and F0 = 70N. How much does the bullet penetrate the wall...