Homework problem Definition and 419 Threads

Homework Statement A tritium nucleus is formed by combining two neutrons and a proton. The mass of this nucleus is 9.106 × 10–3 universal mass unit less than the combined mass of the particles from which it is formed. Approximately how much energy is released when this nucleus is formed...

hi, the question is in the image attached. i just don't get the correct answer. what i did was count the total torque in respect to the pivot and equal it to i*alfa. maybe i am getting the signs and direction wrong or maybe i am misplacing the masses. can some one please write the equation...

Homework Statement Show that lambda = 1 is an eigenvalue of the matrix 2,-1, 6 3,-3, 27 1,-1, 7 and find the eigenvalues and the corresponding eigenvectors Homework Equations The Attempt at a Solution I don't understand how to actually get eigenvalues and...

original pendulum of mass 11 kg with a period of 1.6 sec, displaced an angle of 12 degrees from the vertical. What would its acceleration be in the vertical (y) direction as it reachs the lowest point on its swing? wouldn't it just be -9.8? (since its just the force of gravity acting on it)

Homework Statement A 3.86 kg block slides down a smooth, fric- tionless plane having an inclination of 28◦ . The acceleration of gravity is 9.8 m/s2 . Find the acceleration of the block. Answer in units of m/s2. Homework Equations idk what equation to use? The Attempt at a...

Homework Statement At present, the concentration of uranium 235 in naturally occurring uranium deposits is approximately 0.77%. What will the concentration be one billion years from now? Homework Equations N(t) = No e^ -(ln(2)/half-life)t The Attempt at a Solution i attempted...

Homework Statement A light bulb has a straight metal wire filament of 50 micro metres diameter and 10mm long and when powered with a 5V constant voltage supply it draws 0.5A of current. What happens to the current if the filament is replaced with one of three times the diameter? Homework...

Homework Statement It is well known that for a conservative motion there is a potential. This potential is a function of coordinates only. Prove this. Homework Equations The Attempt at a Solution I think you have to take a definition of conservative motion then for example...

Homework Statement Two 75.0 kg hockey players skating at 6.15 m/s collide and stick together. If the angle between their initial directions was 130°, what is their speed after the collision? (Let the motion of player 1 be in the positive x-direction and the motion of player 2 be at an angle of...

Homework Statement You place 83 moles of hydrogen gas in a balloon of volume 2.8 m3, and find the pressure to be 1.4 times atmospheric pressure. What is the typical speed of a hydrogen molecule? Homework Equations v=(sqrt)((3*Boltzmann Constant*T)/mhydrogen T=pv/nr The Attempt...

Homework Statement At what temperature does a carbon resistor have a resistance of 995 ohms, if it has a resistance of 1000 ohms at 20 degrees? What is its conductivity at the new temperature? Homework Equations The Attempt at a Solution I don't even know where to start.

Homework Statement What is the tangential acceleration of a bug on the rim of a 8.0 in. diameter disk if the disk moves from rest to an angular speed of 75 revolutions per minute in 5.0 s? (b) When the disk is at its final speed, what is the tangential velocity of the bug? (c) One second...

Homework Statement An electric motor rotating a workshop grinding wheel at a rate of 90 rev/min is switched off. Assume constant negative angular acceleration of magnitude 2.50 rad/s2. (a) How long does it take for the grinding wheel to stop? (b) Through how many radians has the wheel...

Homework Statement a robot probe drops a camara off the rim of a 239 m high cliff on mars, where the freefall acceleration is -3.7 m/s^2. a. fiind the velocity wl which the camara hits the ground. b. find the tiime required for it to hit the ground. Homework Equations vf^2= vi^2+2ad...

Homework Statement The pipe assembly shown in the picture supports the vertical loads shown. Determine the reactions at the ball and socket joint (point A) and the tension in the two cords BC and BD. Homework Equations Sum of Forces = 0 Sum of Moments = 0The Attempt at a Solution I first...

Homework Statement In one part of a musical composition, the triangle player in an orchestra plays once every 12 beats. The tympani player plays once every 42 beats. How often do they play together? Homework Equations don't have any The Attempt at a Solution Insufficient...

Homework Statement Presidential elections are held every four years. Senators are elected every 6 years. If a senator was elected in the presidential election year of 2000, in what year would he or she campaign again during a presidential election year? Homework Equations dont know...

Homework Statement Margo has piano lessons every two weeks. Her brother Roberto has a soccer tournament every three weeks. Her sister Randa has an orthodontist appointment every four weeks. If they all have activities this Friday, how long will it be before all of their activities fall on...

Hi everybody, this is my first post on your forum and i hope someone can help me :) the problem is i can figure out how to approuch this problem :s i do know that the process of the air descending is adiabatic but still i can't get it :( thanks for your help guys in advance. Homework...

how do i show that f: [0,1) \rightarrow S^1; t \rightarrow (\cos{2 \pi t}, \sin{2 \pi t}) is a continuous bijection but not a homeomorphism. so i know i have to (i) show f is a continuous bijection (ii) show f^{-1} is not continuous so for (i), surjectivity: if i take a point (a,b)...

I posted this in the advanced forum by mistake so I'm am posting it here as I think it may be more appropriate in this forum. Homework Statement A motor boat is speeding at velocity W0 when the motor is turned off and a scoop is lowered into a still lake. The scoop captures flow with a cross...

Homework Statement For some reason, I cannot seem to get the derivative for this. Homework Equations f(a) =\frac {(2500+0.2t)(1+t)}{\sqrt {0.5t+2}} The Attempt at a Solution f(a) =\frac {(2500+0.2t)(1+t)}{\sqrt {0.5t+2}} \frac {(2500+0.2t)}{\sqrt {0.5t+2}} (1+t) From...

Can you check over my answers to see if my reasoning is correct? Homework Statement #3) "Yesterday I woke up and it was 20°F in my bedroom," said Mert to his old friend Mort. "That's nothing," replied Mort. "My room was -5.0°C." Who had the colder room, Mert or Mort? Homework Equations...

Homework Statement A certain storm cloud has a potential of 1.50 x 10^8 V relative to a tree. If, during a lightning storm, 50.0 C of charge is transferred through this potential difference and 1.00% of the energy is absorbed by the tree, how much sap in the tree can be boiled away? Model...

Homework Statement A model rocket blasts off from the ground, rising straight upward with a constant acceleration that has a magnitude of 79.0 m/s2 for 1.90 seconds, at which point its fuel abruptly runs out. Air resistance has no effect on its flight. What maximum altitude (above the ground)...

Homework Statement A real number x \in R is called algebraic if there exist integers a_{0},a_{1},a_{2}...,a_{n}, not all zero, such that a_{n}x^{n} + a_{n}_{1}x^{n-1} + ... + a_{1}x + a_{0} = 0 Said another way, a real number is algebraic if it is the root of a polynomial with integer...

Is it possible for the critical angle to exist when light goes from water (n=1.33) into glass (n=1.5)? My used the formula sin(critical angle) = n1/n2. I'm a bit confused, should the numerator(n1) always be less dense compared to the denominator(n2).

A cheetah is hunting. Its prey runs for 3.2 s at a constant velocity of +10.0 m/s. Starting from rest, what constant acceleration must the cheetah maintain in order to run the same distance as its prey runs in the same time?

A car starts from rest and travels for 5.9 s with a uniform acceleration of +1.3 m/s2. The driver then applies the brakes, causing a uniform acceleration of -2.1 m/s2. The breaks are applied for 1.60 s. (a) How fast is the car going at the end of the braking period? (b) How far has the car...

Homework Statement John walks 1.60 north, then turns right and walks 1.40 east. His speed is 1.80 during the entire stroll. If Jane starts at the same time and place as John, but walks in a straight line to the endpoint of John's stroll, at what speed should she walk if she wants to...

Could you help me solve this one : Write the the equations of the tangents of the parabole x^2=2y-4 that go through the origin of coordinates. Whats the surface of the figure formed by the parabole and the tangents. I am not sure i have translated thi one in an understanding way :(.

If body A exerts an impulse of say +2Ns on B, then does body A exert an impulse of -2Ns on B providing no external forces act? Thanks

Homework Statement A photon of wavelength 250 nm ejects an electron from a metal. The ejected electron has a de Broglie wavelength of 0.85 nm. (a) Calculate the kinetic energy of the electron. (b) Assuming that the kinetic energy found in (a) is the maximum kinetic energy that it could...

Homework Statement "A car travels a certain distance along a straight road and on the way must stop at traffic lights and obey local speed limits. The figure (not pictured but info filled in below) shows the distance the car travels as a function of time. Choose all the correct answers which...

Homework Statement Point M is the midpoint of RT ( with the lin on top of RT).RM = x and RT = 4x-6. Find the value of x. Homework Equations The Attempt at a Solution I wrote out the equation (RT=4x-6)/2=RM but I am not sure if this is the right approach.

Homework Statement Using Comparison test and LCT, determine whether it is convergent or divergent: (summation n=1 to infinity) sqrt(n+2)/(2n^2+n+1) Homework Equations The Attempt at a Solution i compared it with sqrt(x)/2n^2 which is 1/2n^(3/2) and then the answer showed...

I'm having trouble with this homework problem! Current & Magnetic Field! This problem deals with current and the magnetic fields around these 2 parallel wires. The question is listed below, as is the link to the picture. Thanks SO Much for your help...

Ok, so like i am in this very complicated philosophie of math course with like a little science fiction writing on the side for extra credit, so since the class is like a joke cause i mean it is philosophy after all and not maths (rock on math! why is it that math seems to be useful in...

Homework Statement A golfer rides in a golf cart at a speed of 3.10 m/s for 24.0 s. She then gets out of the cart and starts walking at an average speed of 1.30 m/s. For how long (in seconds) must she walk if her average speed for the entire trip, riding and walking, is 1.90 m/s...

what is the rotational speed of the hand on a clock that measures the minutes? what is the rotational speed of the hand on a clock that measures the seconds?

I cannot figure out this problem...can someone help me? A 3500 air-gap capacitor is connected to a 32 battery. If a piece of mica fills the space between the plates, how much charge will flow from the battery? Express your answer using two significant figures.

Any assistance given is greatly appreciated. Thanks in advance. http://img3.imageshack.us/img3/5519/hw3statics.jpg Thanks again.

\int csc dx = ? [b]I just am seeking confirmation as to whether or not I did this correctly. I apologize beforehand for any formatting errors. \int csc(x) dx = \int 1/sin(x) dx u = sin(x) du = cos(x)dx du / cos(x) = dx u2 = sin2(x) u2 = 1 - cos2(x) \sqrt{}{u^2-1} = cos(x) du...

Homework Statement A carton is given an initial speed of 3.0 m/s up a 22.0 degree plane. a.) How far up the plane will it go? b.) How much time elapses before it returns to its starting point? Ignore friction. Homework Equations F=ma The Attempt at a Solution I have no clue. If...

A fluid of density (rho) flows through a horizontal pipe with negligible viscosity. The flow is streamline with constant flow rate. The diameter of the pipe at Point 1 is d and the flow speed is v. If the diameter of the pipe at Point 2 is d/3, then the pressure at Point 2 is...

Homework Statement The combination of an applied force and a friction force produces a constant total torque of 36.0 N·m on a wheel rotating about a fixed axis. The applied force acts for 6.00 s. During this time the angular speed of the wheel increases from 0 to 10.0 rad/s. The applied force...

http://img502.imageshack.us/img502/8941/webworks4ez6.jpg" . The first answer is 2.5V, but I'm having trouble getting ωt I'm using the equation: V = V0 sin(ωt) --> 2.5V = 5V sin(ωt) --> sin-1(2.5V/5V) = ωt --> ωt = 30 degrees but that's incorrect and so is -30 degrees I've just used an...

Homework Statement Distance of Earth from Sun = 1.50 x 10^11m Period = 365.2 days Distance of Mars from Sun = 2.28 x 10^11km Period of Mars in Earth Years? Homework Equations (Ta/Tb)^2 = (Ra/Rb)^3 The Attempt at a Solution (365.2 days/Tm)^2 =(1.50 x 10^11m/2.28x10^14m)^3...

Homework Statement A simplified model of a bicycle of mass M has two tires that each comes into contact with the ground at a point. The wheelbase of this bicycle (the distance between the points of contact with the ground) is w, and the center of mass of the bicycle is located midway between...

Homework Statement A 0.85kg mass oscillating on a spring w/ spring constant of 45 N/m. How do i determine angular frequency? A 0.85kg mass oscillating on a spring w/ spring constant of 45 N/m. This object reaches a maximum position of 12 cm from equilibrium. Determine: a.) angular frequency...