Hey guys, I've been a member of this site for a while now, looking at other people's homework problems and attempting them as extra practice. I find that reading about what other people have trouble with when attempting physics problems helps me avoid them myself, and it has worked pretty well...
Homework Statement
In Figure (1), a 3.50 g bullet is fired horizontally at two blocks at rest on a frictionless table. The bullet passes through block 1 (mass 1.18 kg) and embeds itself in block 2 (mass 1.85 kg). The blocks end up with speeds v1 = 0.540 m/s and v2 = 1.47 m/s (Figure (2))...
Homework Statement
A 2.5 kg wood block hangs from the bottom of a 1.0 kg, 1.2 m long rod. The block and rod form a pendulum that swings on a frictionless pivot at the top end of the rod. A 12 g bullet is fired into the block, where it sticks, causing the pendulum to swing out to a 33 angle...
1. Homework Statement
In a certain region, the Earth's magnetic field has a magnitude of 5.30e-5 T and is directed north at an angle of 57° below the horizontal. An electrically charged bullet is fired north and 11° above the horizontal, with a speed of 681 m/s. The magnetic force on the...
I was reading a recent paper on arXiv.org on a novel simulation of MOND, and surprisingly they addressed the Bullet Cluster, which I guess is one of the more serious problems for MOND. What was even more surprising was that they said this posed a problem for Lamda-CDM models as well. Here is the...
Homework Statement
Hi,
A gun totally immersed underwater and shoot a bullet.
Q1. Would there be a trail of bubbles behind the bullet?
Q2. If there are bubbles, where do they come from?
Q3. If there are bubbles, would the sum of the volume of all bubbles be equal to the volume of...
Homework Statement
This is a two part question.
Kim holds a 2.0kg air rifle loosely and fires a bullet of mass 1.0g. The muzzle velocity of the bullet is 150m/s. What is the recoil speed of the rifle?
^ I got -.075m/s
Part Two:
If Kim in the previous questions holds the rifle tightly...
Homework Statement
A bullet (mass 15 g) moving at a speed of 425 m/s is brought to a stop in 3.5 cm in a block of wood.
Homework Equations
Find the force on the bullet, assuming that it is constant.
The Attempt at a Solution
what law should we use?
0 - 1/2*m*V^2 = m*g*0.035 + F*0.035 ?
Forgive my naivety. I used to know math, but have sort-a fallen off the bicycle some 30 years ago. I hope I don't go all ballistically ignorant.
I have a problem trying to calculate muzzle velocity for pellet rifles. Specifically, I assume there is a way to do it without a chronograph and come...
Homework Statement
A lead bullet at 320K is stopped by a sheet of steel so that it reaches its melting point of 600K and completely melts If 80% of the k.e of the bullet is converted into internal energy calculate the speed with which the bullet hits the stee sheet.
Homework Equations...
Homework Statement
A 50g bullet traveling horizontally at 200 m/s embeds itself in a much more massive wooden block initially at rest on a horizontal surface ( \muk = 0.10). The block then slides 1.2 m toward an ideal spring and collides with it. The block compresses the spring (k=600.0 N/m) a...
Homework Statement
A .01kg bullet traveling at 800m/s hits a disk with a radius of R=.1m at R/2 and leaves with a speed of 400m/s. what is the angular speed of the disk right after? (omega)
Homework Equations
conservation of angular momentum
Inertia for a disk
The Attempt at...
Homework Statement
A 47.00 g bullet hits and becomes embedded in a 5.10 kg wooden block which is hanging from a 2.50 m long string. This causes the block to swing through an arc of 23.50o. What was the speed of the bullet before it hit the block?
mb = 0.047kg
mw = 510kg
r = 2.50
theta =...
7. 0/10 points All Submissions Notes Question: SerPSE8 11.P.037.
Question part
Points
Submissions
1 2
0/5 0/5
4/100 2/100
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A wooden block of mass M resting on a frictionless, horizontal surface is attached to a rigid rod of length script i and of negligible mass. The rod...
Homework Statement
A 50g bullet traveling horizontally at 200 m/s embeds itself in a wooden block, initially at rest, on a horizontal surface (μk=0.1). The block slides 1.2m toward a spring and collides with it. The block compresses the spring (k=600 N/m) by 20 cm. Find the mass of the wood...
Homework Statement
Calculate the change in entropy when a lead bullet of mass 10 grams traveling at 500 m/s hits a very large volume of water. Assume that the bullet was initially at 150 degrees Celsius and the water was at 25 degrees Celsius.
Homework Equations
K=\frac{1}{2}\,{{\it...
Homework Statement
A 17 g bullet is accelerated in a rifle barrel
103 cm long to a speed of 392 m/s.
Use the work-energy theorem to find the
average force exerted on the bullet while it is
being accelerated.
Answer in units of N.
Homework Equations
The Attempt at a Solution...
Homework Statement
A 7g bullet moving horizontally at 200 m/s strikes and passes through a 150 g tin can sitting on a post. Just after impact, the can has a horizontal speed of 180 cm/s. What the bullet's speed after leaving the can? ANSWER = 161 m/s
Homework Equations
7g = .007 kg
150 g...
The probability density for bullet hitting a target is given by f(x,y)=C.Exp(-(x^2+y^2)/2sigma square. What is the value of C. Sketch the curves of constant density in the XY plane. What kind of curve are they? What are the most probable hitting areas?
Homework Statement
A uniform stick 1.3 m long with a total mass of 260 g is pivoted at its center. A 3.6 g bullet is shot through the stick midway between the pivot and one end. The bullet approaches at 250 m/s and leaves at 140 m/s. With what angular speed is the stick spinning after the...
Homework Statement
An 8-g bullet is shot into a 4.0-kg block, at rest on a frictionless horizontal surface. The bullet remains lodged in the block. The block moves into a spring and compresses it by 5.0 cm. The force constant of the spring is 2200 N/m. In the figure, the initial velocity of...
Homework Statement
The speed of a rifle bullet may be measured by means of
a ballistic pendulum in the following way. The bullet, of
known mass m and unknown speed v, embeds itself in a
stationary wooden block of mass M, suspended as a pen-
dulum of length L. This sets the block to...
Homework Statement
A 26.2 g bullet is fired horizontally into a
1.32 kg wooden block resting on a horizon-
tal surface (μ = 0.173). The bullet goes
through the block and comes out with a speed
of 298 m/s.
If the block travels 3.01 m before coming to
rest, what was the initial speed of...
Homework Statement
A 125. gram bullet traveling at 300. m/s strikes and sticks into a stationary 5.00 kg block of wood. The combined bullet + wood initially slides on a horizontal frictionless surface until they encounter a second horizontal surface with a coefficient of kinetic friction...
Homework Statement
Problem from the book:
"A 7 gram bullet, when fired from a gun into a 1 kg block of wood held by a vise, penetrates the block to a depth of 8 cm. This block of wood is next placed on a frictionless horizontal surface, and a second 7 gram bullet is fired from the gun into the...
Homework Statement
diagram: http://goo.gl/uPl0
Part A
A bullet of mass 0.0175 kg and speed vb passes completely through a pendulum bob of mass 1.3 kg. The bullet emerges with a speed 0.5vb. The pendulum bob is suspended by a stiff rod of length 1.1 m and negligible mass. The acceleration of...
Homework Statement
When a bullet strikes a block of wood originally at rest, the bullet becomes embedded into the wood block which travels 1.70 m after the collision. If the mass of the bullet is 5.26 g and the mass of the block is 2.40 kg, what is the speed of the block immediately after the...
Homework Statement
When a bullet strikes a block of wood originally at rest, the bullet becomes embedded into the wood block which travels 1.70 m after the collision. If the mass of the bullet is 5.26 g and the mass of the block is 2.40 kg, what is the speed of the block immediately after the...
Homework Statement
The following mathematical model was suggested for the variation in pressure inside the 10-mm-diameter barrel of a rifle as a 25-g bullet was fired:
p(t)=(950MPa)e^{-t/(0.16ms)}
where t is expressed in ms. Knowing that it took 1.44 ms for the bullet to travel the length...
Part 1
1. The only two forces acting on a body have magnitudes of 20 N and 42 N and directions that differ by 60°. The resulting acceleration has a magnitude of 20 m/s2. What is the mass of the body?2. F=ma3. I am not sure how to solve this because I'm used to being able to use trig like cos...
Homework Statement
A gun can fire shells in any direction with the same speed v0. Ignoring air resistance and using cylindrical polar coordinates with the gun at the origin and z measure vertically up, show that the gun can hit any object inside the surface
z = \frac{v_{0}^{2}}{2g} -...
Homework Statement
(1)A 5g bullet leaves the muzzle of a rifle with a speed of v=320m/s. what force (assumed constant) is exerted on the bullet while it is traveling down the 0.82m-long barrel of the rifle?
(2)Two forces are applied to a car in an effort to move it. what is the resultant of...
Homework Statement
A rifle with a barrel length of 56 cm fires a 10 g bullet with a horizontal speed of 350 m/s. The bullet strikes a block of wood locked in position and penetrates to a depth of 13 cm.
What resistive force (assumed to be constant) does the wood exert on the bullet...
Today I had a question from a student that made me think. Maybe I am just over thinking this.
We were discussing the independent nature of horizontal and vertical components of motion. This was done through shooting a dart gun. We came to the conclusion that (without air resistance) the...
Hi all, this has been bugging me so maybe you can help me out.
In the front window of my house, there is a dent in the glass that looks somewhat similar to this:
http://www.flickr.com/photos/guerra/2557095422/"
However, there is not hole in the glass. But the shape of the dent is...
Homework Statement
A hot air balloon is ascending straight up at a constant speed of 8.10 m/s. When the balloon is 13.0 m above the ground, a gun fires a pellet straight up from ground level with an initial speed of 28.0 m/s. Along the paths of the balloon and the pellet, there are two...
If a train goes past an observer at 100km/hour and someone on the train fires a bullet from a gun in the direction the train is going at 700km/hour, then relative to an observer, that bullet will go past at 800km/hour. Einstein made a statement of the type that if a person on the train holds a...
Hello Mighty Ones!
I know from an FBI study that a bullet shot at a 90 degree angle into a metal plate, the splatter from the bullet goes out at a 20 degree angle.
The question is... is there a rule or something that says if I angle that 90 degrees to angle down X degrees will the...
Ok so I want to know if conservation of momentum can be applies in a case of shooting a bullet to the wall I am talking about in the x direction of course since gravity is an external force in the y direction so a let say I shoot a bullet in a straight angle to the wall so it has huge x...
Homework Statement
A bullet leaves the muzzle of a rifle at an unknown velocity and strikes a wooden block that is suspended by a piece of string.
If the block swings backwards to make an angle of 40 degrees, at what velocity must have the bullet been traveling when it struck the block?
mass of...
I was wondering why a bullet spins. From what I read a spinning bullet shoots straighter, but I don't really understand why since the Magnus Effect would cause it to drift or does the gyroscopic inertia compensate for this?
Also, does gyroscopic inertia cause the rotational axis to be stable...
Hi, everyone.
Please help us work through a hypothetical situation that we came up with at work. We're chemists, not physicists, and none of us have had to do physics equations since undergrad. So, we're kind of hopeless without help.
We were thinking about the following scenario. In the...
A 5.00 g bullet is fired into a 6.00 kg block, which is suspended from a string 1.00 m long.
The string deflects through an angle of 12.0°. How fast was the bullet moving?a
Transitional KE = ½ mv2
Rotational KE = ½ I2 Elastic PE = ½k L 2
I'm not sure those are the right formulas...
Homework Statement
A bullet is shot horizontally into a block suspended by two strings. The bullet remains embedded in the wood and the wood and bullet together suspend upward.
a) Explain why the horizontal momentum of the bullet-wood system is conserved during the collision even though the...
Homework Statement
A little while ago I made a thread about the drop of a bullet due to gravity on a bullet with a constant velocity. Constant velocity is unrealistic, so I am going for a little more realism here.
I am doing this assuming that I have detailed information about distance...
Homework Statement
An 8.00 g bullet is fired into a 160 g block that is initially at rest at the edge of a table of 1.00 m height. The bullet remains in the block, and after the impact the block lands d = 2.2 m from the bottom of the table. Determine the initial speed of the bullet...
the lob pass is thrown with an initial speed of 21.5 m/s and its time of flight is 2.97s. What is its launch angle?
The bullet pass is thrown with a launch angle of 25 degrees. What is the initial speed of this pass? What is the time of fight of the bullet pass?
what formulas and how is...
Homework Statement
An 19-g bullet is shot vertically into an 5-kg block. The block lifts upward 5 mm. The bullet penetrates the block in a time interval of 0.001 s. Assume the force on the bullet is constant during penetration. The impulse on the block due to capture of the bullet is closest...