Initial Definition and 1000 Threads

Homework Statement A rock is thrown from the top of a twenty meter high building at the angle 53 degrees above the horizontal. IF the horizontal range of the throw is equal to the height of the building, what is the speed of the rock? How long is it in the air? What's the velocity of the rock...

Homework Statement A dog can jump to a height of 0.20 m. What is the initial velocity of the dog? Homework Equations v=v0+at The Attempt at a Solution I'm not sure if this is suppose to be a trick question. Are they talking about the gravitational acceleration? v=v0+at v0= 0...

The electric potential a distance r from a point charge q is 2.40×104 V. One meter farther away from the charge the potential is 6500 V. Homework Equations V=kq/r The Attempt at a Solution 6500 = 8.99x10^9 (q) / 1m q = 7.230 x 10^-7 then, r= kq/v r= 8.99x10^9 (7.230 x 10^-7)...

[Please Help!] Find Initial Velocity (With Wind Factored In) I can't do it =\. Q: What equation would I use to find initial velocity? Given: Wind Speed, Wind Angle, Coordinates of Origin, Coordinates of End Point, (Distance), Projectile Mass, Theta (Angle to Use) Here's my repost from a...

1.05 g MgO is added to 110.15ml HCL with an initial temperature of 21.5 degrees Celsius and a final temperature of 34.5 degrees Celsius. calculate the KJ of energy released for the reaction. assume that 4.18 J of energy is required to change the temperature of one mL of solution to one Celsius...

Greetings all, I have a question in regards to my initial conditions. The problem as given is: ut=uxx with u' = 0 at x=0 and u=0 at x=L I was also given u={1 0<x<L/2, 0 L/2<x<L I understand the set up of the problem and the solving of it for the most part, however I'm having...

What is the longest possible hole-in-one for this golfer? Neglect any distance the ball might roll on the green and assume that the tee and the green are at the same level. in m and: What is the minimum speed of the ball during this hole-in-one shot? please explain your answers :D...

Homework Statement A grasshoopper jumps 1.00 m from rest, with an initial velocity at a 45.0 degree angle with respect to the horizontal. Find the initial speed of the grasshopper (answer is 3.13 m/s) The maximum height reached (answer is .250m) Homework Equations...

Homework Statement Particle A of mass 1kg is at rest 0.2m from the edge of a smooth horizontal table 0.8m high. It is connected by a light inextensible string of length 0.7m to particle B of mass 0.5kg. Particle B is initially at rest at the edge of table closest to A but then falls out...

Hello everyone. I have a problem listed below. I am very lost due to the fact that my teacher literally just gave us this problem to do and expects us to hand it in soon without even teaching/talking about this topic in class. I did some research over the Internet on IMF, but still am pretty...

A object is dropped from a height of 5.29 X 10^6 m above the surface of the Earth. What is its initial acceleration. The acceleration of gravity is 9.81 m/s^2 and the radius of the Earth is 6.37 X 10^6 m. Answer in units of m/s^2. So my problem is that I was sick today and missed the...

Homework Statement Assuming the best high jump record from a standing position in a school was 1.52 m, what initial velocity was needed for this jump? neglect any sideways motion. Homework Equations velocity equation The Attempt at a Solution I don't really understand how to do...

Homework Statement The acceleration of a particle is given by ax(t) = 2.90t - 2.06 Q. Find the initial velocity v0x such that the particle will have the same x-coordinate at time t = 4.06 as it had at t = 0. Homework Equations vx = v0x + \intaxdt evaluated from 0 to t. x = x0 +...

http://i48.tinypic.com/1o4ow9.jpg why in this circuit they say that in t<0 the voltage on both capacitators is 12 volts?? if both points of each capacitators is connected to the voltage source directy then 12 volts is ok. but here we have a resistor between them this resistor drops...

Homework Statement Assume acceleration due to gravity is 9.8ms^-2 It has been said that in his youth George Washington threw a silver dollar across a river. Assuming that the river was 75m wide, (a) what minimum initial speed was necessary to get the coin across the river (b) how long was...

Homework Statement A baseball is thrown at 20 degrees to the horizontal. The ball travels a horizontal distance of 18 meters when it returns to the same level as the instant it had been thrown. The total time it traveled between these points is 2.1 seconds. Determine the initial velocity (Vo)...

Homework Statement A cannon shoots straight up into the air a cannonball which reaches a maximum height of 600m. What was the initial velocity of the cannonball when it was fired from the cannon. (Note: this problem contains all the information necessary to be solved.) use g=10m/s^2...

A boy tosses a coin straight up to 2.8 m. Suppose the height when the coin leaves his hand is 1.2 m. What was the initial speed of the coin when it left his hand? I'm just confused as to what equation to use. And I don't know whether to assume the acceleration is -9.8 m/s^2. Thanks.

I'm having a bit of trouble understanding the concepts of momentum conservation. Let's say I'm standing on a frictionless surface and I throw a 3kg brick horizontally with a velocity of 4m/s. In this scenario I can see that I'm going to be repelled backwards at a velocity of 12/my mass in kg but...

Hi: This is my first post and I'm not sure if this is the right forum. Please redirect if necessary. I'm new to nonlinear regression, but from what I've read I realize that making "good" initial guesses for the model parameters is very important, otherwise a "best fit" may not result...

Homework Statement The problem is given as follows: Solve dy/dt + y = 0.5, y(t=0)=1Homework Equations The Attempt at a Solution I separate the y terms from the t terms, which gives me dy(-y+0.5)=dt I integrate both sides to get -ln(-y+0.5)=t+C C is the constant, I combine the constants from...

Homework Statement An entertainer juggles balls while doing other activities. In one act, she throws a ball vertically upward, and while it is in the air, she runs to and from a table 5.60 m away at a constant speed of 2.10 m, returning just in time to catch the falling ball. Homework...

what is the solution for y in this peculiar ODE ? A\left(y,x\right)=\frac{dy}{dx}+B(x)(1-y) with initial conditions : \frac{dy}{dx}=\left0 \ldots , y=0 \frac{dy}{dx}=\delta(x-x_{0})\ldots,y=1 moreover \int^{\infty}_{-\infty}Adx=\int^{\infty}_{-\infty}Bdx=1

While going through some textbook problems I encountered several circuits that had initial conditions like the one attached where there's an initial current of 8mA when the switch is open. What's the source of that current? how can there be a current if the circuit is open...

Homework Statement A bullet of mass m is fired into a large block of wood, mass M, suspended by two long cords. The bullet comes to rest in the block so that the system swings upwards, coming to rest after traveling through a vertical distance h. Find in terms of m, M, and h: the initial...

Homework Statement Question Reads: " A passenger in a hot air balloon throws a ball with an innitial unknown velocity. the ball accelerates at 9.8m/s down for 2.0s. at which time its instantenous velocity is 24m/s [45 below the horizontal]. determine the balls innital velocity "...

Homework Statement Use the equation derived about to calculate the exact value of the initial speed that will produce a circular orbit of the satellite at an altitude of 1000 km above earth.2. Homework Equations -Derived equation provided: Finward = Fg m1 v^2 / r = Gm1m2/r v^2 = Gm2/r v=...

Homework Statement A Saturn V rocket has a mass of 2.75x10^6 Kg and exerts a force of 3.3x10^6N on the gases it expels. determine the initial vertical acceleration of the rocket. 2. The attempt at a solution heres my attempt... F=3.3x10^6N Fg= M=2.75x10^6 Fnet-MA F-Fg=ma F-mg=ma...

Homework Statement The figure shows a block on a frictionless surface attached to a spring. The block is pulled out to position x_i = 20 cm, then given a "kick" so that it moves to the right with speed v_i. The block then oscillates with an amplitude of 44 cm. Image of the problem -...

Homework Statement A 7.0-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 Momentum The Attempt at...

Homework Statement A projectile is launched with an intial speed of 60m/s. If it reaches a maximum height of 150m above this level surface then its horizontal range (in m) is ____ ? Homework Equations v^{2} = vo^{2} + 2ay y = yo + Vot + 1/2at^2 The Attempt at a Solution Vo =...

Homework Statement a rocket is fired at an angle of 45degrees from the horizontal, if it travels 22m(horizontally) for a total time of 1.9 secs, what is its intitial veritical and horizontal velocity? Homework Equations i tried using s=ut+.5at^2 The Attempt at a Solution i came up...

Homework Statement Use the Laplace transform to solve the following initial value problem: x' = 7 x + 5 y, y'= -2 x + e5t, x(0)=0, y(0)=0 Find the expressions you obtain by taking the Laplace transform of both differential equations and solving for Y(s) and X(s) Homework Equations...

Did I do this right an F=ma need to find Initial Speed? Need help on this. A car whose mass is 2600 kg can produce an unbalanced braking force of 2765N. Calculate the car's initial speed in order to have a stopping distance of 3036.3m. Vi=? So... m=2600kg F=2765N s=3036.3m Vf=0 So I...

Homework Statement A 29.0 g ball is fired horizontally with initial speed v0 toward a 100 g ball that is hanging motionless from a 1.10 m-long string. The balls undergo a head-on, perfectly elastic collision, after which the 100 g ball swings out to a maximum angle θmax = 50.0° see image for...

What is a realistic timeline for the LHC initial experiments? ie. with a machine this massive and complicated, how long does it take experimenters to get to know the detector and backgrounds (I've heard many a theorist complain about how the experimentalists still don't use next-to-leading-order...

Homework Statement (D^3 - D^2 + D - 1)y = e^x and y(0) = 0, y'(0) = 1, y"(0) = 0 Homework Equations D = d/dx The Attempt at a Solution Factoring the left side of the equation gives : (D^2 + 1)(D - 1)y = e^x Which has roots of +/- i and 1. So y(c) = Ae^x + Bsin(x) +...

General solution of initial value problem --dont understand problem is asking me?? Homework Statement Find a value for y-sub-0 for which the solution of the initial value problem: y' - y = 1+ 3sin t y(0) - y-sub-0 remains finite as t approaches infinity. (i called it "y-sub-0" , just...

Homework Statement Find general solution of equation (t^3)y' + (4t^2)y = e^-t with initial conditions: y(-1) = 0 and t<0 book answer gives y = -(1+t)(e^-t)/t^4 t not = 0 Homework Equations The Attempt at a Solution (t^3)y' + (4t^2)y = e^-t get integrating...

Homework Statement Given your assigned projectile launcher determine the muzzle velocity. angle of launcher = 45degrees distance to bottom of barrel = 25.6 cm distance traveled when fired = 119.2cm Ignore Air resistance Homework Equations I don't know where to start since I have...

Homework Statement Find out the launch velocity from the launcher (the absolute starting point aka x=0) Angle (degrees) Height(cm) Average Distance Traveld(cm) 0 99.0 220.73 30 104.3 307.8 45 106.6 380.4 60 108.5 319.2...

Homework Statement Solve the differential equation: y' + 2y = te^-2t with initial conditions y(1) = 0? Please show me what I am doing wrong... (or right).. also please don't show me shortcut i need to know where I am going wrong thanks. Homework Equations The Attempt at a...

Homework Statement The spectral lines of the light from distant galaxies exhibit a Doppler redshift due to the motion of the galaxy away from our own. For a particular galaxy, three spectral absorption lines are observed from the Earth to have wavelengths of 164.4 nm 168.4 nm and 177.5 nm...

Homework Statement A ball having mass 1.2 kg is connected by a string of length 1.6 m to a pivot point and held in place in a vertical position. A constant wind force of magnitude 23 N blows from left to right.If the mass is released from the vertical po- sition, what maximum height...

I have to find the kenetic energy lost in the problem. I have both initial and final kenetic energy, how do i calculate the percent loss? I tried final over initial times 100 but that is not correct.

1. Find C and S in terms of the initial position and velocity of the oscillator. Give your answers in terms of x_0, v_0, and omega. Separate your answers with a comma. 2. x(t) = X_0 + v_0*t + 0.5at^2 x(t) = C*cos(omega*t) + S*sin(omega*t) 3. Taking the derivative of x(t): v(t)...

Homework Statement An elevator with a small initial upward velocity being raised by a cable. The tension in the cable is constant. Find the magnitude of the tension in the cable. Be certain that the method you are using will be accurate to two significant figures. Acceleration=10 m/s^2...

which will strike the ball at the fastest speed? -one launched upward at a certain angel -one launched downward -one launched perfectly horizontally I am guessing 1, since it has the additional height to fall under gravity influence

Homework Statement the question says, consider a newly formed globular cluster, with a total mass 10^6 times mass of the sun and an initial mass function dN/dm = a.m^-2.35 in the mass range 0.1 - 20 times mass of the sun, where m = M/mass of the sun. find the constant a. (answer : 1.9...