Height Definition and 1000 Threads

Homework Statement A man stands on the roof of a building of height 14.6m and throws a rock with a velocity of magnitude 30.8m/s at an angle of 33.2∘ above the horizontal. You can ignore air resistance. Calculate the maximum height above the roof reached by the rock. Homework Equations...

Hi all, I'm trying to do something that might be impossible, but seems to me should have a solution: Finding the height (or displacement) of a long, thin rod or wire under horizontal compression forces at the ends (pinned, not clamped) causing it to bend into a stable arch-like shape given...

A container is filled with water to a height of 1.5m. A hole at the bottom let's water squirt out horizontally at a height of 2m above the ground. How fast is the water moving that shoots out the hole?

Homework Statement An object is thrown downward with an initial (t = 0) speed of 10 m/s from a height of 60 m above the ground. At the same instant (t = 0), a second object is propelled vertically upward from ground level with a speed of 40 m/s. At what height above the ground will the two...

Homework Statement A ball is launched at an angle of 38° at 16m/s off of the top of a building, the ball finally hits the ground after 45seconds. What is the height of the building? Gravity is normal 9.80m.s squared. The answer to the problem is 9480m. Homework Equations I just needed...

Homework Statement A ball is thrown upwards from a point near the sidewalk next to a tall office building. At some later time an occupant of the building, exactly 5.1 meters above the point from which the ball was released, sees it pass her window with a speed of 2.9 m/s. Calculate the...

Here is the question: I have posted a link there to this thread so the OP can view my work.

Homework Statement A skier starts from rest at height H on the side of a valley. The other side of the valley rises to a rounded peak at 4.0m. Assuming the skier goes down one side of the valley and up the other, what is the maximum value of H for which the skier remains in contact with the...

Homework Statement Problem Statement: Imagine you had a very long straw, one end is in the ocean (sea level) and the other end is in space. Air pressure at sea level is a standard atmospheric pressure and space is a perfect vacuum. Plot "height of water in straw" vs. time...

Here is the question: I have posted a link there to this thread so the OP can view my work.

My daughter was given this problem in an exam. She could not do it and was never given the solution. I can do the problem using trig but she has not been taught trig yet. She says that it can be done without trig using a more simple method that she doesn't know. Could somebody please explain...

Homework Statement A man starts riding on a frictionless roller coaster track at initial velocity v_{o}. At point A the radius of the bend is r. a) What is the maximum v_{o} such that when the cart gets at point A it stays on the track? b) Using you answer in a) what should h' be such that...

Homework Statement A dog jumps a distance, L, and a maximum height, H, where the dog only has horizontal velocity when it travels through the hoop. What is the speed of your dog when he leaves the ground? What is the speed of your dog when he goes through the loop? Both answers should NOT...

Homework Statement I did an experiment investigating what effect height has on force and now i need a theoretical value to compare it to Homework Equations f=ma but i don't think acceleration is constant here The Attempt at a Solution f=ma f=0.104x9.8 f=1.01 i got 49 N with...

Homework Statement A diver weighing 784 N stands on a diving board 13.6 m above the surface of a pool. The diver steps off the edge and falls into the pool. The pool does -12290 J of work on the diver. How far below the surface of the pool (depth) does the diver reach? Homework Equations...

Homework Statement the initial velocity of a projectile is 150 m\s .the angle between the velocity vector and the trajectory at the projectile's maximum height is a) 90 b) 45 c) zero d) 63.1 e) 36.9 Homework Equations Vox= vx = Vocosθ Vy = Vosinθ-gt Range (R) = (vo)^2*sin(2θ)/g...

Does a yo-yo lose all its translational kinetic energy when it reaches the bottom and turns around? It seems at the bottom the string should give the axle of the yo-yo a violent tug, so maybe some of the translational kinetic energy is converted to rotational kinetic energy and is not lost as...

Homework Statement A man holds a double-sided spherical mirror so that he is looking directly into its convex surface, 44.8 cm from his face. The magnification of the image of his face is +0.22. What will be the image distance when he reverses the mirror (looking into its concave surface)...

Homework Statement A block of mass 20 g sits at rest on a plate that is at the top of the fluid on one side of a U-tube as shown below. The U-tube contains two different fluids with densities ρ1 = 1070 kg/m3 and ρ2 = 650 kg/m3 and has a cross sectional area A = 4.6 * 10-4 m2. The surfaces...

Homework Statement http://i6.minus.com/jErr8PMddiofz.png Homework Equations V of cone = pi/3 (r^2)h The Attempt at a Solution I'm assuming this is correct and that dh/dt = 0.2 ft/min I basically substituted a value of h in for the radius so I wouldn't be doing multi-var...

I realize the answer depends how where in the atmosphere speed is increased more, and whether a higher orbit or lower orbit is desired, and the shape size and weight of the craft. But I'm just curious about typical ratios. About what fraction of the fuel goes to lifting the weight of the...

Homework Statement A body is dropped from a height of 300 m. At exactly the same moment another body is projected from the ground vertically upwards with a velocity of 150 m.s^-1. Calculate the … 3.2.1 time it will take for the two objects to reach the same height. The Attempt at a...

Homework Statement A baseball is thrown just so that it is able to pass a wall 10m high at a distance that is 1000m away. If it is aimed 30 degrees above the horizontal, what is the initial speed of the baseball? Homework Equations relevant equations shown at the attempt at the solution...

Hey everyone, I'm currently doing research at a University, I've been working on a problem for a few hours and wrote up a quick paper that shows my derivation of a certain height based on an angle. Basically the experiment is looking at optical properties of graphene, but for this to happen we...

As we all know,Potential energy =mgh.If someone digs a hole and place a ball at 0 height,the potential energy should be zero but it falls somehow.How is this possible?

Homework Statement An ball is launched at a 45 degree angle with an initial speed v0. What is its speed at its max height? Homework Equations n/a The Attempt at a Solution This problem does not contain any calculations. I was wondering if somebody could explain how the speed at...

Homework Statement You let a ball roll from rest from the top of a ramp sitting on a table. If the top of the ramp is 12 cm above the top of the table, how fast is it moving when it reaches the bottom? Use g=9.8m/s/s Homework Equations Convert 12 cm to meters an you get .12. Then...

Homework Statement An object is shot vertically upward and has a speed of 12 m/s when it reaches one fifth of its maximum height. a. What is the initial speed of the object? b. What is the maximum height of the object? Homework Equations Free falling objects The Attempt at a Solution...

Finding velocity after collision if you know mass and height. Help! Homework Statement A 50 gram ball enters a a pendulum with mass 200 g. The pair then swings up to a height of 11 cm. find the velocity immediately after the collision? Then find initial velocity of ball before collision...

Homework Statement A firework rocket is fired vertically upwards from the ground. It accelerates uniformly from rest with an acceleration of 8.0 ms−2 for 5.0 s after which time the fuel of the rocket has all been used. Sketch graphs to show how the gravitational potential energy and the...

Why is the height "/1000"? Homework Statement In the attached example problem, why did the height, originally in millimeters then converted to meters, be divided by 1000? Note: This is a thermodynamics related question? Or at least from a thermo textbook. I thought that the units...

You are climbing in the High Sierra where you suddenly find yourself at the edge of a fog-shrouded cliff. To find the height of this cliff, you drop a rock from the top and 8.50s later hear the sound of it hitting the ground at the foot of the cliff. Ignoring air resistance, how high is the...

Hello All, Unfortunately I'm pretty bad in physics, so I would like to ask from you. I have two problems: 1. I have a ball. The soccer kick the ball in a given angle, and I would like to find out what is the speed and height of the ball. Is there any equation or function what can I...

Homework Statement http://imgur.com/b7y3Khb A small cart slides without friction on the loop-the-loop track, as shown, starting from rest at initial height h. The weight of the cart is W. When the cart is at the point A --- the top of the loop --- the force on the track is 0.6 W. Then what...

Homework Statement Utility Pole BC is guyed by cable AB as shown. The tension in cable AB (TAB) acting at point B creates a moment about point O (MO) equal to -900i+Myj-315k lb-ft, where My is unknown. a) What is the length of the pole (LBC)? b) What is the magnitude of the tension, TAB...

Homework Statement A brick is thrown upward from the top of a building at an angle of 10.1◦ above the horizontal and with an initial speed of 6.74 m/s. The acceleration of gravity is 9.8 m/s^2. If the brick is in flight for 2.5 s, how tall is the building? Answer in units of m...

Homework Statement In the problem, we are to consider two candles, call them C1 and C2, with different heights and different thicknesses. Call the height of C1 H1, and for C2, call it H2. The taller candle burns can burn for 7/2 hours, and the short one, 5 hours. After two hours lapses, the...

Homework Statement Given a disc of radius 'R' with a charge 'h' above the center of the disc, find the electric field on the charge.Homework Equations ##E = \frac{kQ}{d^2}##The Attempt at a Solution I can find the charge density from a ring then integrate over R: ##\sigma = \frac{Q}{A}##...

Homework Statement A particle is projected with an initial speed u from a point at a height h from the horizontal plane. Find the equation for maximum range of the particle. Homework Equations R=u^2sin2θ/g H=(usinθ)^2/2g The...

Homework Statement A diver jumps off a 3.00 meter high diving board with an initial velocity of 1.75 m/s vertically upward. a) What is the diver's veolcity when she reaches the water? (assume the surface of the water is 3.00 meters below the board.) b) What is the highest point the diver...

Homework Statement Hi, I have inserted a picture of the problem: I have to find x, the altitude, or height of the triangle. x is the height of the larger triangle, and is perpendicular to the base of 13. It divides the base into segments of length 4 and 9. This was a question on...

... factoring in fluid dynamics, not just Newtonian physics... At a given height, the object will possesses 75% of the kinetic energy of when it initially began moving. Mass is irrelevant. Given variables: -Drag coefficient -Fluid density -Cross-sectioned area -Displacement -Initial and final...

Homework Statement A particle is projected from a point o with initial velocity u up a plane inclined at an angle 60° to the horizontal. The direction of projection makes an angle ∅ with the horizontal. The maximum perpendicular height is H. prove that H = u^2( sin^2(∅) ) / g Homework...

Homework Statement 2. A 0.30 kg bullet is fired from a gun with a velocity of 410 m/s. The bullet then becomes embedded into a piece of wood with mass 5.5 kg hanging as a pendulum at rest. To what height will the piece of wood swing? m1=.3kg v1=410m/s m2=5.5kg v2=0 Homework Equations...

Homework Statement A spring is launched from the ground at 2.3 m/s t an angle of 78° to the ground. What is the max height of the spring? How far did the spring travel? Homework Equations ##\vec{v}_R = 34 m/s## ##\theta = 78°## The Attempt at a Solution First things first, get my...

Here is the question: I have posted a link there to this topic so the OP can see my work.

Homework Statement A ball of mass 100 g is projected straight up with a speed of 5 m/s from the floor. Another ball of mass 50 g is hung from the ceiling by a light string at a height of 1.00 m directly above the first ball, so that the projected ball collides elastically with it. Calculate...

We all know the air at the ceiling is warmer than the air at the floor because "hot air rises" due to the density gradient. But I started wondering how drastic is this effect actually? Noticeable, at all, say, in a normal 11 foot ceiling room? Make whatever assumptions you need (still air, no...

Hello all I have a question I was hoping someone could answer for my homework. A 78.0-kg boulder is rolling horizontally at the top of a vertical cliff that is h1 = 16 m above the surface of a lake, as shown in the figure below. The top of the vertical face of a dam is located d = 110 m from...

Homework Statement There is a fire in a building, so the fireman connects a hose to a hydrant that pumps 2 litres of water per second. The exit of the hose has and area of 15cm^2. Which is the maximum floor of the building that the water can reach considering that it exits the hose at an...