Height Definition and 1000 Threads

So Imagine a ball moving off a frictionless cliff with a velocity v to the right, at the bottom of the cliff the surface has friction. So after the collision, the x component of the velocity would be reduced, and the angular momentum would be fixed clockwise because the frictional impulse...

To approximate windspeeds we normally use the natural logarithm relation: u_air = V ln [ (z-d) / z_0 ]Where: V - Characteristic speed, constant z - height from the ground z_0 - roughness length, constant d - zero plane displacement, constant The Betz limit tells us that in theory that the max...

Hi, I am doing a project for school where I am calculating at what height a balloon would pop from pressure while rising. At the point I am now, I have the initial pressure and the pressure it would pop at. I know work = pressure * change in volume, and that at some point I will need to use the...

Homework Statement A 11-kg dog jumps up in the air to catch a ball. The dog's center of mass is normally 0.20 m above the ground, and he is 0.50 m long. The lowest he can get his center of mass is 0.10 m above the ground, and the highest he can get it before he can no longer push against the...

Hello! 1. Homework Statement I need to find the instantaneous height of a liquid during the simultaneous filling and emptying (through a hole) of a cylinder. I have varying Qin at incremental time of 1 sec. with cylinder area=5 cm and orifice area=0.5 cm. Homework Equations Torricelli's...

Homework Statement I searched around and found a manual, so this time I have the complete question in English (I'll use different numbers though, because mine is the 8th edition, and the manual is from the 14th, but it's not something that affects this exercise): 2.98) An alert hiker sees a...

The other day I was at a river listening to some rapids. The sound produced by the rapids appeared to vary in pitch depending on how high up I was (squatting down to the ground and standing up produced about a fifth in the variation of the pitch); and I can't think why it should be? Many Thanks

Homework Statement A 5.0kg block initally traveling at 11m/s moves up a 30degrees incline. A frictional force of 9.4N acts on the block as it moves up the incline. What maximum vertical height, h, will the block reach? m = 5.0kg, vi = 11m/s, vf = 0m/s, Fr = 9.4N, Homework Equations...

Homework Statement A particle is thrown in the angle pi/3 radian with speed 10m/S. Find the time of movement if the maximal height is equal to the distance of fall. Homework Equations v^2-voy^2=2gh The Attempt at a Solution 0-10^2*3/4=2*10*hmax hmax=3.75 v0x*2t=3.75 v0*cos60*2t=3.75...

Homework Statement Height - 15m Time when ball hits the ground after upward throw 3 s. I have been trying to find intitial speed with these formulas : d=v_initial*t-0.5*g*t^2 and v=v_initial+g*t Please help to understand how to find initial speed and after what time the ball is at 15m height...

Here's the situation: A small block of wood of inertia mb is released from rest a distance h above the ground, directly above your head. You decide to shoot it with your pellet gun, which fires a pellet of inertia mp. After the block has fallen a distance d, the pellet hits it and becomes...

Homework Statement Two particles are thrown horizontally from different heights with equal initial speeds. Find the difference of heights h1-h2 if the object fall to the ground at the same time. Homework Equations h=voyt+gt^2/2 The Attempt at a Solution As voy=vox=0, t1=t2, the difference of...

Homework Statement Question :- A block of mass ##5 kg## is attached to a spring. The spring is stretched by ##10 cm## under the load of the block. A impulse is provided to the block such that it moves up with a velocity of ##2 m/s##. Find the height it will rise. Homework Equations ##F_s =...

Homework Statement The particle thrown under the angle pi/6 rad. with the horizontal direction achieves the height h for t1=10S when going up and t2=50S when going down. Find initial speed v0 and height h. Homework Equations h=v0y+gt^2/2 The Attempt at a Solution As h1=h2...

Homework Statement A very Slippery ice cube slides in a vertical plane around the inside of a smooth, 20 cm diameter horizontal pipe. The ice cube's speed at the bottom of the circle is 3.0 m/s Vi = 3.0 m/s Height at top= 2(.20) = .40 Vf = ? Homework Equations KE(initial) + PE(initial) =...

Homework Statement A 28-kg rock approaches the foot of a hill with a speed of 15 m/s. This hill slopes upward at a constant angle of 40.0∘ above the horizontal. The coefficients of static and kinetic friction between the hill and the rock are 0.75 and 0.20, respectively. a)Use energy...

Both the problem and my attempt at a solution are provided. However, I become stuck. The answer book (question 27, as pictured in the next post, the upload size limit made me create a second post and both images are about 4mb), suggests that I use dV/dH, which is the portion of the cone volume...

Homework Statement A toy car rolls off of a table at an initial angle of 0 degrees and an initial velocity of 2.81 m/sec. The ball hits the floor 1.55 m (horizontally) from the edge of this table. How tall is the table? Homework EquationsThe Attempt at a Solution So far I have: Vo=(2.81 m/sec)...

Considering a body falls a free fall and g is changing, what is the formula of the height as a function of time?

I recently did a level survey however am a little stumped over a calculation. I am trying to calculate the Reduced Level using the "Height of Instrument" method. I know how to do the calculations etc. so I am not asking for this to be done for me. It is more of a general question about this sort...

Homework Statement If a ball is dropped from a height (H) its velocity will increase until it hits the ground (assuming that aerodynamic drag due to the air is negligible). During its fall, its initial potential energy is converted into kinetic energy. If the ball is dropped from a height of...

Homework Statement I work as a supplemental instructor for an intro physics class. As I was preparing my worksheet for this week I came across this problem. A basketball player can jump to a height of 55cm. How far above the floor can he jump in an elevator that is descending at a constant...

I've been reading up on capillary action in a tube, and I have some questions: Say we insert a tube in a pool of fluid; Jurin's Law expression is ##h=\frac{2\sigma \cos \phi}{r\rho g}##. However, this height is not the height of the fluid measured from the bottom of the tube, but rather the...

Homework Statement A cannon that is capable of firing a shell at speed V_0 is mounted on a vertical tower of height h that overlooks a level plain below. (a) Show that the elevation angle \alpha at which the cannon must be set to achieve maximum range is given by the expression...

Homework Statement A particle is projected with speed v at an angle α to the horizontal. Find the speed of the particle when it is at a height h. Answer: √v2 - 2gh 2. The attempt at a solution a. Since PE gained is KE lost we need to find KE and PE. KE = 0.5 * m * (v sin α)2 (the vertical...

Homework Statement An elevator with a mass of 500kg goes up 30 stories in 12 seconds doing 12000J of work. Find how high the elevator goes. Homework Equations I'm not exactly sure what equations are needed for this question but in class we have been using these equations. Ek=1/2mv^2 Ep=mgh...

Homework Statement I am given a water tank, a small plastic cup, and some gravel. How could I use Archimede's principle to determine how much gravel to put in the plastic cup such that it sinks to a certain point (namely the rim), but then floats, so that no water is let inside the cup...

Homework Statement A cylindrical glass tube (linear thermal expansion coefficient ##\alpha##) contains liquid (volume thermal expansion coefficient ##\beta##). The height of the tube is ##h_{t,0}## and the height of the liquid inside of it is ##h_{l,0}##. If the temperature changes of an amount...

Homework Statement I am going to paste the problem word for word, so you can have all the exact information that I have: You’re part of a team that’s designing a rocket for a specific mission. The thrust (force) produced by the rocket’s engine will give it an acceleration of a feet per second...

Hello everyone, I was playing around with some equations regarding air resistance. I tried to calculate the height that is reached by an object that is projected vertically into the air. However something seems to go wrong when integrating. Starting with the equation of motion \begin{align*}...

Homework Statement I have a table that needs to be filled out. In each column, potential and kinetic energy are given, but height and velocity are left blank. Ex: PE = 20 J, KE = 0 J, h = ?, V = ? Homework Equations KE = 1/2mv^2 U = mgh The Attempt at a Solution I'm totally stumped. How can I...

We are using the following pump to measure the strain on a special tube. http://www.instechlabs.com/Support/manuals/HABP.pdf This special tube is connected on each side to another tube that is connected to one of the two connectors on the pump. (The two connectors of the pump were put parallel...

Homework Statement The longest homerun hit by Miguel Cabrera in the 2012 season occurred at Comerica Park and had an initial y-component of velocity of 19.8 m/s and an initial x-component of velocity given as m/s, where is some value left undetermined. Assume the ball left the bat 1.22 m off...

Homework Statement Sam, whose mass is 75 kg, stands at the top of a 12-m-high, 100-m-long snow-covered slope. His skis have a coefficient of kinetic friction on snow of 0.07. If he uses his poles to get started, then glides down, what is his speed at the bottom? Homework Equations v =...

Let ##\vec{a}## be the gravitational acceleration along the curve. Then ##|\vec{a}|=a=-g\sin\theta## and ##\vec{a}=a_x\,\vec{i}+a_y\,\vec{j}=-g\sin\theta\cos\theta\,\vec{i}-g\sin^2\theta\,\vec{j}## My question is why does the solution below ignore the direction of ##\vec{a}## and calculate...

Why is the coefficient of restitution of a ball independent of the height it is dropped from? A mathematical explanation would be best. Thank you.

Homework Statement A soccer ball is kicked at a 45° angle. If the ball is in the air for 3 s, what is the maximum height achieved Homework Equations y=viy + 0.5 x ay x t The Attempt at a Solution i used trig to get the vertical and horizontal components i got 2.2 for each side (as there the...

Homework Statement I want to calculate the height h of the skier in this figure Homework Equations potential energy and kinetic energy and there is no friction The Attempt at a Solution mgh = 0,5 *m*v^2 v=√ (2*g*h) Now calculate the h when he goes up mgh= 0,5 *m*√ (2*g*h)^2Am I doing...

Hi, I am trying to build (or at least conceptually) design a diy autonomous lawnmower. I want to add an automated grass cutting height mechanism. I have never worked with lawnmowers but through basic googling know that most lawnmowers have simple mechanisms in wheels to change cutting height...

Homework Statement The speed of a projectile when it reaches its maximum height is one-half its speed when it is at half its maxi- mum height. What is the initial projection angle of the projectile? Homework Equations Vf2 = vi2 + 2axThe Attempt at a Solution I know that the speed at the top...

I graphed different heights from which I had dropped a bouncing rubber ball on the y-axis and the time taken for it to bounce on the x-axis. The function came out to be quadratic, but I do not know why. If someone can show mathematically why this is, that'd be splendid. Thank you.

I am pumping water out of a pond that is being dug with a 30 h.p. centrifugal water pump. I am lifting the water about fifteen feet and discharging it at the same level as the pump. I feel lowering the pump near the water level and pushing the water up the fifteen feet would be more efficient...

Homework Statement Homework Equations Volume for cylinder = Pi (r)2 h Optimise : 1. make the best or most effective use of (a situation, opportunity, or resource). 2. rearrange or rewrite (data, software, etc.) to improve efficiency of retrieval or processing. The Attempt...

Homework Statement For a concrete column of constant cross sectional area, what is the maximum possible height if the compressible strength is 2.0 x 107 N/m2? The density of concrete is 2.3 x 103 kg/m3. Homework Equations \frac{F}{A} The Attempt at a Solution I am not really sure what I am...

Hi everyone, I have been hunting all over the Internet for an explanation to changes in the blood pressure when sitting, standing or lying down. I know the complex mechanisms that are involved but I need an equation for an ideal system with the heart in the middle and the pressure that needs to...

Homework Statement A ball is shot from ground into the air. at height 8.3m, its velocity is 7.8i + 6.5j. Find Maximum height rise, horizontal distance traveled and magnitude of velocity just before the ball hits the ground. Homework EquationsThe Attempt at a Solution So i got the total...

NO TEMPLATE BECAUSE THREAD WAS STARTED IN WRONG FORUM A wrecking ball is a heavy steel ball, usually hung from a crane that is used for demolishing large buildings. Suppose we had a crane with a wrecking ball with a mass of m1 = 12,000 lbs. The crane produces a displacement on the ball of a...

Homework Statement You are standing at a horizontal distance of 712 m from the location from which fireworks are being shot straight up. The temperature of the air this night is 23.6°C. The timer below measured the time from the explosion to when the sound reached your ears. Use all this...

Homework Statement Homework Equations The Attempt at a Solution There is solved problem on change in water height with respect to time. I understand it but there is the b part of the question. It asks that what's if the top of the tank is open to the atmosphere? I think nothing would...

Homework Statement Using the diode equation with moderate forward bias, show numerically how to find the Schottky diode barrier height and the ideality factor via a graphical plot. Homework Equations I = I0e(eV/nkT) I0= AA*T2e-eφb/kT with n= ideality factor and φb= Barrier height The Attempt...