Homework Definition and 998 Threads

Homework Statement A backpacker throws a rock horizontally off of a cliff with an initial velocity of 11.7 m/s, and the rock lands 17.3 m away from the base of the cliff. What is the final vertical velocity of the rock? Round your answer to 2 decimal places. Homework Equations Δd = vot +...

Homework Statement Calculate how much force you would have to apply to the crate to get it to go at constant speed up a 30 degree ramp. Homework Equations Using kinetic friction for equation. The Attempt at a Solution I couldn't find the formula for kinetic friction which also includes...

1. Play the first two levels of the game http://www.physicsgames.net/game/Gravity_Master.html Make the ball move in different ways. Write a one page report on whether the motion is like that of a ball in the real world. Explain your observations using classical mechanics.2. None provided.3...

1. Question A 0.145kg baseball moving horizontally at 35.0m/s strikes a bat and is popped straight up to a height of 55.6m before turning around. If the contact time is 0.50ms, calculate the average force on the ball during the contact. Homework Equations p=mv Δp=mΔv=fΔt Ek=0.5mv^2 (?) Ep=mgh...

Homework Statement I have Fx = -800sin60 + 600cos45 -450sin75=-703N Fy= 800cos60 -450cos75 + 600cos75 = 707.8N FR = 997N , but te ans given is FR = 867N , is my ans wrong ? or the given ans wrong ? Homework EquationsThe Attempt at a Solution

Homework Statement [/B] Problem: Sanjay's air boat starts from rest and accelerates at 9.1 m/s2 for a distance of 216 meters. How fast is it moving at the end of the 216 meters? And how much time will it take to cover this distance? Known: Vi = 0m/s A = 9.1m/s D = 216m Homework Equations...

Homework Statement Homework Equations Can someone please help me with this question? These are the formulas you can use http://www.sqa.org.uk/files_ccc/PhysicsSQPN5RelationSheet.pdf Thanks

Homework Statement Homework EquationsThe Attempt at a Solution

Homework Statement Problem states : A student walks off the top of the CN Tower in Toronto, which has height h and falls freely. His initial velocity is zero. The Rocketeer arrives at the scene a time of t later and dives off the top of the tower to save the student. The Rocketeer leaves the...

Homework Statement Problem : During your summer internship for an aerospace company, you are asked to design a small research rocket. The rocket is to be launched from rest from the earth’'s surface and is to reach a maximum height of 990 m above the earth'’s surface. The rocket’'s engines give...

<< Mentor Note -- Thread moved from the technical math forums, so no HH Template is shown >> Hey guys, could use some insight here... So this is a basic story problem: "I paid $22.30 for 6 new golf balls and 10 used balls. If each new ball costs $.65 more than a used ball,how much did I pay...

Homework Statement I need to show that $$\del*\vec{A(\vec{r})}=\frac{\mu}{4\pi}\int{\frac{\vec{J{vec\r'}}}{\vec{R}}}d\tau=0$$ where A is the vector potential and R refers to "script r" or (r-r') where r is source point of charge and r' is the measurement point. tau refers to a volume integral...

Homework Statement [/B] If 1.20 grams of salicylic acid is reacted with excess methanol, what mass of ester should you expect to achieve theoretically? Molar masses of.. salicylic acid is 138.13g/mol methanol is 32.05g/mol ester (methyl salicylate) is 152.16g/mol Mole ratio...

True or False: If three forces, all of equal magnitude, act on a single object can these forces be arranged to cancel out, so that the object is in equilibrium? (F) If three forces, all of unequal magnitude with the other two, act on a single object, it is never possible for these three...

I 1. A man of mass m = 80.0 kg hangs from a rope down into a hole. The rope goes over a massless pulley and is connected to a block of rock of mass M = 200 kg, which is lying on a frictionless horizontal surface. The distance between pulley and man is 5.00 m; between pulley and block 20.0 m...

Homework Statement A proton is composed of three quarks: two "up" quarks, each having charge +2e/3, and one "down" quark, having charge -e/3. Suppose that the three quarks are equidistant from one another. Take the distance to be 3×10-15 m and calculate the potential energy of the subsystem of...

Homework Statement Look I have an exercise about trusses in vector mechanics. It's the following: https://scontent-lax3-1.xx.fbcdn.net/hphotos-xfp1/v/t1.0-9/12003339_1645511085733429_8210043018491702007_n.jpg?oh=4955534403fb6f3f5f9a40c9c0b8ecbc&oe=569761ED I have to determine the forces in...

Homework Statement Consider the figure below, we need to find the charge on Q_0, both charges Q are negative. It is given that the net charge on Q_A is zero. The figure of the problem is attached. The Attempt at a Solution I understand how to get the solution except for one part. I'm just...

A charge Q is placed at a distance a = 3m and a charge q is placed at a distance b For what value(s) of b is the x-component of the force maximized? I know to maximize the force we need to maximize F_Qq = k Qq b/(3^2 + b^2)^{3/2}. To do this we need to set the first derivative to zero and...

Homework Statement A solid insulating sphere of radius a = 4.3 cm is fixed at the origin of a co-ordinate system as shown. The sphere is uniformly charged with a charge density ρ = -421 μC/m3. Concentric with the sphere is an uncharged spherical conducting shell of inner radius b = 14.6 cm, and...

Homework Statement Four charges of 2*10^-7 are placed on the corners of one face of a cube of 15 cm. A charge of -2 * 10^-7 C is placed at the center of the cube. What is the force on the charge at the center of the cube? Homework Equations F = k q_1*q_2/r^2 The Attempt at a Solution...

Homework Statement Homework Equations ## 2as = v^2-u^2 ## ## v = 0 ... \text{at maximum height}## ## \therefore s = \frac{-(u)^2}{2a} \\ a = -g \\ \therefore s = \frac{-(u)^2}{-2g} = \frac{(u)^2}{2g} ## Please explain using only the Three equations of motion and not anything related to...

Homework Statement A cannon, when aimed vertically, is observed to fire a ball to a maximum height of L. Another ball is then fired with the same speed, but with the cannon aimed up along an incline of length L, inclined at an angle θ. What should θ be so that the ball travels the largest...

Homework Statement Two trains run in opposite directions on parallel tracks. Train A is 30 meters long and runs east to west at 60 mph. Train B is 45 meters long and runs west to east. It takes 0.5 seconds for the trains to pass each other. How fast is train B travelling? What is the velocity...

Homework Statement I've attached a url with a picture of the problem setup and diagram https://instagram.com/p/7nYNXTscre/ Homework Equations I used the equation V = KΣiqi/ri to solve for potential at A and B The Attempt at a Solution For Va I used K((Q/d)+ (2Q/(d^2+d^2)^.5)) I just plugged...

Hello! I am working on homework for my general relativity class, and I am very confused about how to tell the difference between spacelike, timelike, and null vectors, and the book is very unhelpful. Relevant equations Consider two four vectors a and b whose components are given by: a^α=(-2, 0...

Figure (a) shows a narrow charged solid cylinder that is coaxial with a larger charged cylindrical shell. Both are nonconducting and thin and have uniform surface charge densities on their outer surfaces. Figure (b) gives the radial component E of the electric field versus radial distance r from...

Homework Statement Find the magnitude and direction of net electric field at the center of the square array of charges. Find E_x and E_y The square array of charges http://postimg.org/image/4gf94ymmf/ The Attempt at a Solution [/B] My attempt at drawing in the force vectors...

Homework Statement For which non-zero value of x is the equation -x^ -4 = (-x)^ -4 true? Explain. Homework Equations None. Other than applicable exponent laws. The Attempt at a Solution I know how to use the guess and check method. But I was wondering how to reach the answer faster and how...

Homework Statement A neutral atom is known to have a nucleus with a positive charge of 2.4 x10-12 C. How many electrons does the atom have? Homework Equations q=Ne The Attempt at a Solution None

I had a question. If a glass rod, with a charge of 5.4x108 C touched another insulator so that all of the excess electrons are shared equally. What would the final charge on the rod be? I don't understand how to reach the answer of 2.7 x108 C. Thanks in advance. :)

1. What acceleration would be needed by a car speeding up from 10 m/s to 15 m/s in 80 m?2. The equations I have at my use right now are: V = at D = (1/2)(a)(t)^2 T = square root of 2D / A A = change in velocity / time3. I honestly can't wrap my mind around how to solve this

Homework Statement I Have tried to solve a problem about infinite potential well with a delta well in the middle, but I haven't the results and so I can't check if the proceeding is wrong. I post the steps that I have followed hoping someone can help me to understand. We have a particle in 1D...

Homework Statement In the given DC circuit, while switches S1,S2 are open, conductor C1 is charged with Q10, and conductor C2 is not charged. After the switch S1 is closed, through conductors flows the amount of charge q1=40µC. After the switch S2 is closed, through conductors flows the amount...

Homework Statement Air enters a compressor at 100kPa and 20 oC in steady flow rate . Air is compressed to 1 Mpa. The heat loss is 10% of the power of the compressor . Air enters with speed of 50m/s in a surface of 0,009 m2 and leaves with speed 120 m/s from a surface of 0,0005 m2. Find the...

I noticed the scan was cut off on the second image at the bottom right, but I came up with x= 31/5 My first test in Calc I begins tomorrow and I want to know that I'm headed in the right direction. I think I understand to some extent how logarithms can be expanded and condensed though I'm...

Homework Statement A tank has a saturated liquid at 0.2 MPa. An amount of heat is transferred until the pressure in the tank became 0.1 MPa. If the volume of the tank 1 m3. Determine: 1- The final state of the water 2- The mass of the vapor in the tank 3- The work 4- The process on P-v...

So, I'm about to take an Optics exam, and while I can easily do most of the last years' exam problems, there are some which I cannot solve for different reasons (perhaps some gross oversight?). Yesterday I stumbled upon this: 1. Homework Statement (my own translation from Catalan) We have a...

Homework Statement Problem 1 Assuming that the people in D and C all have KTP (Citizen ID in my country) IDs, let: D = {x |x is the KTP ID of a student in your Basic Calculus class}, C = {y |y is the KTP ID of the biological father/mother of a student in your Basic Calculus class}, and f : D...

Hi, I need some help with this homework from my Electromagnetism course. I hope this is the correct place to post this. (Please excuse any potential english mistake I made trying to translate this). Problem 1: Copper (conductor) sphere of radious R with an spheric bubble inside placed at...

Homework Statement One of the problem in my homework is a question that ask is ASCII table (https://en.wikipedia.org/wiki/ASCII) a function and require me to answer mathematically which i don't know how. Homework EquationsThe Attempt at a Solution I think ASCII table is not a function because...

I'm at a loss. I can't figure it out. Please help. Last year's 6th grade boy to girl ratio was 3 to 4. This year's 6th grade boy to girl ratio is 5 to 6. If the total number of students were the same this year as they were last year; what is the number of 6th grade boys last year if there are...

Homework Statement Planning a new stunt where he will be shout out of a cannon into the back of a speeding utility vehicle the sit slopes downhill at 10 degrees and the cannon will launch him at 35Km/Hr at and angle of 30 degrees as shown in the attached picture Homework Equations I cannot...

Homework Statement the question exactly states that a 8000 kg pulls a train of 5 wagons each of 2000 kg along a horizontal path now if the train exerts a force of 40000 N , and the track offers a friction of then calculate a_NET FORCE b_ACCELERATION OF TRAIN c_FORCE OF WAGON 1 ON WAGON 2 2...

Homework Statement A car travels north with a velocity of 5.2-m/s for 92-seconds. It then turns east, and with the same speed travels for a further 22-seconds. Calculate the magnitude of the final displacement of the car. Now give the direction of the final displacement of the car. Give your...

None of these questions are homework problems, they're just confusing things that homework has caused 1. In math, what is the difference between a bracket and a parenthesis? Also what about the right symbols for ordered pairs , is that strictly these [ ] or these { } 2. If you have lots of...

Homework Statement : Question 1: A body is projected with speed u at an angle theta with the horizontal. Find the change in velocity in time t. Question 2: A body is projected with speed u at an angle theta with the horizontal. Find the speed of body at a height h. Both the questions are...

The lack of an ability to mark homework threads solved when they are is a discouragement to would-be homework helpers. Sometimes I browse for problems needing help but give up after looking at a few threads only to find that they are solved and no longer in need of input. There are some closed...

Homework Statement There is a wagon (W) on wheels with a vertical pole of 2m. (mass 20kg) On the top of that pole there is a rope pendulum with an attached mass (M) of 10kg and length 1m. The starting position is a pendulum angle of 60°. No friction taken into account. What is the speed of the...

Homework Statement A block of 55 g is sliding down a ramp of 35 degrees of inclination. The hypotenuse of the ramp is 63 cm and the height is 36 cm. vi = 0 as the block starts at rest. Homework Equations vf = vi + a(t) d = vi*t + (a(t)^2)/2 kinetic energy = (mv^2)/2 The Attempt at a Solution...