What is Line: Definition and 1000 Discussions

Homework Statement There's a person on the ground in (0,0,0). An object comes from the sky and hits the ground at (a,b,0), but continues propagating, that is, it does not stop. I need to find the minimum distance between the person and the object. All we know is that the person is in (0,0,0)...

Homework Statement Write the parametric and cartesian equations of the line passing through ##P = (-\frac{3}{10}, 0, \frac{1}{10})## and parallel to $$r : \begin{cases} 10x + 4y - 3 = 0 \\ x + z = 0 \end{cases}$$ Homework EquationsThe Attempt at a Solution Since the two lines have to be...

Here is the Problem Here is the construction, Hoping that I have done it correct "State with reasons that $\angle$ ACB is bisected by line OC" Many THanks (Party)

Homework Statement Water skiers often ride to one side of the center line of a boat, as shown in the figure (Figure 1) . In this case, the ski boat is traveling at 15 m/s and the tension in the rope is 90 N.If the boat does 3700 N of work on the skier in 54.8 m, what is the angle θ between the...

I'm referring to the black hole itself, not some object falling in it.Thanks.

It's finally here! (Over) Post your experiences and track the results here. I live in a small town near Philadelphia, PA and the line at the poll a few minutes after it opened was a good 50yds/100 people long outside the building. That would probably take an hr to get through, so I left...

I am measuring a communications bus with an oscilloscope at various points along the line. I understand that there will be reflections at each stub as well as at the ends of the bus if the impedance doesn't match. I also understand that these reflected signals will add/subtract with the...

This question occurred to me a few days ago and it's been bugging me ever since. Consider a circle in the coordinate plane with center P(x,y) and radius R, where R < D, D being the distance from the origin to the circle's center. There are two lines tangent to the circle (T1 and T2) that pass...

There is a graph in the form of $x^2-2x-3$ determine the value of $\sqrt{3}$ to the nearest decimal place by drawing an a suitable straight line What must be that straight line ? Usually these kind of problems are solved using the quadratic equation Many thanks :)

Why is there a shunt capacitance in a transmission line, but not in a normal circuit (non-transmission line).?

Hi, Say you have a two conductor transmission line in TEM mode. The E and B field's will look something like the picture below with the E field in blue and the B field in red. The E field should point in the direction of the current, as it's what makes the charges move. The E field in the...

Consider a curve ##C:{\bf{x}}={\bf{F}}(t)##, for ##a\leq t \leq b##, in ##\mathbb{R}^{3}## (with ##x## any coordinates). oriented so that ##\displaystyle{\frac{d}{dt}}## defines the positive orientation in ##U=\mathbb{R}^{1}##. If ##\alpha^{1}=a_{1}dx^{1}+a_{2}dx^{2}+a_{3}dx^{3}## is a...

My professor shown us in class how to find the slope but I still don't understand

Homework Statement Consider the cone defined by z = √ x 2 + y 2 . By defining new coordinates ρ, φ where x = ρ cos φ, y = ρ sin φ, show that the line element on the cone is ds^2 = 2dρ^2 + ρ^2dφ^2 . Why does this result prove the cone has flat geometry? Homework Equations x=rcosφ y=rsinφ The...

Why can't hydrogen gas on the stars be detected by using line emission spectrum of hydrogen. Why must we use line absorption spectrum to detect?

<< Mentor Note -- poster has been reminded to fill out the Attempt at the Solution part of the Template in future HH threads >> 1. Homework Statement An object of mass m is at rest at the top of a smooth slope of height h and length L. The coefficient of kinetic friction between the object and...

Homework Statement find the slope of tangent line to curves cut from surface z = (3x^2) +(4y^2) - 6 by planes thru the point (1,1,1) and parallel to xz planes and yz planes ... Homework EquationsThe Attempt at a Solution slope of tnagent that parallel to xz planes is dz/dy , while the slope of...

Homework Statement The equation ## f(x,y) = f(a,b) ## defines a level curve through a point ## (a,b) ## where ## \nabla f(a,b) \neq \vec 0##. Use implicit differentiation and the chain rule to show that the slope of the line tangent to this curve at the point ##(a,b)## is ##-f_x(a,b)/f_y(a,b)##...

Homework Statement Given the points ##A (1, -1, 0)## and ##B (4, 0, 6)##, find the point ##P## of the line ##s## so that the triangle ##ABP## is a right triangle in ##B##. Calculate the area of the triangle. ##s : \begin{cases} x = 1 + 4t \\ y = 2 - 3t \\ z = 3 \end{cases}## ##\vec v_s = (4...

Homework Statement Given two planes, P1, P2. Find parametric equations for the line of intersection between the two planes. Homework Equations P1 = 2x -3y + 4z = 3 P2 = x + 4y - 2z = 7 The Attempt at a Solution Let N1 be the normal vector to P1, and N2 be the normal vector to P2. Then, N1...

Homework Statement If a, b and c are coplanar vectors related by λa+μb+νc=0, where the constants are non-zero, show that the condition for the points with position vectors αa, βb and γc to be collinear is: λ/α + μ/β + ν/γ = 0 Homework Equations Dot product Cross product Tripple product Vector...

Any of you guys know of any instrument to record both the DC and at the same time the AC transient of a DC line. Thanks.

Hi everyone Does anyone help about unit of below MCNP line for neutron? Is it "neutron*barn/cm^2" right ? fm14 (1 108 102) And also what's the unit difference between "fm14 (1 108 -6 -8)" and "fm14 (1 108 -6 )" ? Many thanks

Homework Statement I have to find for which values of the real parameter ##b## the following plane is orthogonal to the following line: ##\pi : 5x + (2b - 1)y - (1 + 8b)z + 3 = 0## ##s : \begin{cases} x + z - 4 = 0 \\ x - 3y + z + 2 \end{cases}## Homework EquationsThe Attempt at a Solution For...

Homework Statement A point moves on a curve \vec { r } with constant acceleration \vec { A } , initial velocity \vec { { V }_{ 0 } } , and initial position { \vec { { P }_{ 0 } } } b. if \vec { A } and \vec { { V }_{ 0 } } are parallel, prove \vec { r } moves in a line c. Assuming \vec {...

Homework Statement Find for what real parameters the line ##r## is parallel to the plane ##\pi##. ##r: \begin{cases} x - 3y + 3 = 0 \\ 2y + z - 5 = 0 \end{cases}## ##\pi : 6x - (a - 1)y + 3az - 11 = 0## Homework EquationsThe Attempt at a Solution So, the only method I know is to put the three...

Homework Statement The line spectrum of a certain substance consists of three prominent lines; blue (B), yellow (Y) and red (R). When the spectrum is examined with a diffraction grating having d = 4 * 10-6 m, it is found that the sequence of lines, moving from the centre, is B, Y, R, B, Y, B...

In this thread let's forget math, we don't have math to describe these energies anyway. Observation tells us that at extremely high energy densities there is some expansive force that vastly overwhelms everything else. Expansion has become the only viable explanation to what we observe. So I...

Explain why the graph of the function g (x) = x^3 - 2x + 1 intersects the line y = x in each of the intervals (-2, -1), (0, 1) and (1, 2). i hope someone can help me with this. To be honest i do not even know where to start. i sketched g(x) and y=x and i don't see them intersect in the...

Homework Statement Determining the best resistance for my simple circuit consisting of a diode, battery, and resistor. Doing this using Load- Line Analysis Homework Equations ID = VD - V / R - Given by KVL[/B] (I can disregard n-pretend ) The Attempt at a Solution [/B] Here I have...

Homework Statement So, I'm doing a long exercise, you can check here the first part: https://www.physicsforums.com/threads/checking-if-the-following-lines-are-coplanar.885948/ The second part asks me to find, if one of the couple of lines are skew, the orthogonal line to two skew lines...

Homework Statement when we calculate the electric field due to a plane sheet or the magnetic field due to a wire,are we calculating it at a single point or the whole field due to the total wire? Homework EquationsThe Attempt at a Solution

Homework Statement Homework Equations The z component of the field: $$E_z = \frac{-Qh}{2\pi\varepsilon_0 (r^2+h^2)^{\frac{3}{2}}}$$ The Attempt at a Solution I tried to choose a cylinder for my Gaussian surface such that the radius of it matches with the distance d I am trying to find and...

I found in Thompson "From Error-Correcting to Sphere Packing and Simple Groups" this on page 131 How do you compute m/n in a finite field? Take the equivalence class 5 given above. Why does 2/5 and 18/22 give 5? thanks

Homework Statement A lossless transmission line has an inductance of 9.0 nH / m and a capacitance of 3.6 pF / m. a) What is the line's characteristic impedance? b) Calculate the phase constant of a frequency of 1 GHz. Homework Equations Equation of characteristic impedance of a transmission...

Homework Statement Find: The angle between the force vector and the line AO, and the magnitude of the projection of the force along the line AO Homework Equations cos(theta)=(A*B)/(|A|*|B|) The Attempt at a Solution I thought that since I'm given the force F in cartesian form, that I would...

I want to the line integral in the following picture: The field is the blue arrows that go left to right, and the path is the orange line that is going from right to left. Just by looking at the picture, it is clear that the result will be negative, but when I set up the integration this is...

Not really a question suited for the template...maybe shouldn't put this in Homework section, but it's for a class. My write files were being weird so I started some investigating. Below is an excerpt from the code. 58 OPEN(unit=33,file='random2.txt',status='unknown') 59...

Sorry I couldn't finish the title. I ran out of space. Anyway, here's the question: A uniformly charged, infinitely long line of negative charge has a linear charge density of -λ and is located on the z axis. A small positively charged particle that has a mass m and a charge q is in circular...

Homework Statement Let A, B and C be distinct vectors in V3 with B and C non-parallel. a. Find an equation for the plane containing both the line through A parallel to B and the line through A parallel to C. b. Verify that the two lines actually lie in the plane. Homework EquationsThe Attempt...

So here is the situation, I just got to know a certain person and I was recently notified through my Line that he added me as his friend. I have his phone number but he doesn't have mine. All he has about my contact is my e-mail. However, when making a Line account I was not asked to input my...

Find locus of mid point of line segment intercept between real and imaginary axis by the line $a\bar{z}+\bar{a}z+b=0,$ where $b$ is areal parameter and $a$ is a fixed complex number such that $\Re(a),\Im(a)\neq 0$ My Attempt:: Let $z=x+iy$ and $a=x_{0}+iy_{0}$, Then put into...

I am a bit confused on source impedance and Tline impedance, when both are equal. Let's say source impedance is 50 ohms and Tline imepdance is also 50 ohms. Why does the incident wave divide between the source impedance and tline impedance. The impedance is same, so reflection co-efficient...

Say a line equation is expressed with the General equation of Ax + By + C = 0; can one just simply rearrage this into the form of y= mx + b?

Homework Statement Figure 2: Homework EquationsThe Attempt at a Solution 3.2) I made an equation for the input voltage and input current Vi = Vs*(Zi)/(Zi+Rs+Rm) Ii = Vs/(Zi+Rs+Rm) I am a bit confused about what voltages V1 and V2 are measuring, and what do they mean by using the phase ...

I am trying to find the slope of the tangent line of this polar equation: r = 4 + sin theta, (4,0) I put the equation into wolfram alpha and it gives me a 3D plot. If someone could help me find the slope of the tangent line, I would really appreciate it. Thank you.

Homework Statement If the normal at P(ap^2 ,2ap) to the parabola y^2 = 4ax meets the curve again at Q(aq^2, 2aq), show that p^2 +pq+2=0 Homework Equations Point-slope form The Attempt at a Solution I tried putting y=2aq and x=aq^2 but I can seem to simplify the whole thing other than...

i have a frame-buffer , and i want to draw a line using assembly language . i cannot work with decimal numbers . what's the best and most efficient method ? thank you .

Homework Statement Evaluate \int_C \vec{F} \cdot d\vec{r} Where \vec{F} is the field generated from a circular thread of radius b in the xy plane, with magnitude j in the direction \hat{\varphi} (i.e. not along the curve, I take it) C: (x,y,z) = b(1+ \cos{\alpha}, 0, \sin{\alpha}) 3. The...

GH is a straight line. the coordinates of G are (-2,8) the midpoint of GH is (5,-3) work out the coordinates of H