Lift Definition and 593 Threads

I essentially want to understand weather or not an aerofoil with a zero attack angle will generate lift, i.e. using only Bernoulli. I have attached an image to illustrate my question, will the orange block lift if airflow is passed horizontally over the top of it? Many thanks

[SIZE="2"]Hello everybody , i'm new here .. so i hope that you help me in this problem .. i have to make an analysis for a double scissor lift , it has to lift 4000 kg , for a length of 2 meter ,, i have to calculate fatigues ,buckling ,deflection , welding ,screws and the material...

Hi All. I am looking to determine the torque/power/rpm. needed to lift a 4 kg. load 150 mm vertically in 10 seconds. I need to use a 6 volt dc. gear motor mounted vertically and connected to a 12 mm dia. acme lead screw ( steel ) with a 3 mm pitch and 48 % efficiency...

I'm clueless how to start!. Here is the description: A canal operating company is proposing to build an inclined plane to lift boats between two points with a vertical height difference of 55m. Currently the boats have to travel a distance of 6km through 19 canal locks to achieve the same...

NOOB ALERT - I'm not trying to design a helicopter or a spaceship or something ridiculous, I just want to design a little hovercraft with a computer fan, so don't get all indignant and righteous at me. Anyhoo, I found this Lift equation and tried experimenting with some numbers, just to get a...

1. A block weighs 2N. What is the force required to move the block up by 2m? a) 0N b) 1N c) 2N d) 4N Wanna hear from experienced teachers and personnel on this question.

Hello, everyone! I'm studying Nakahara's book, Geometry, Topology and Physics and now studying the connection theory. I come across a problem. Please look at the two attachments. In the attachment , Nakahara said we could use the similar method in the attachment to get \tilde X, but why...

1. I am stuck. Could anybody push me in the right direction? Best Regards Lasse

I'm having a bit of a disagreement with someone and I hope some of you can enlighten us. It sounds rather silly but the debate is around the physics used in a video game (Batman Arkham City). In this game, the character can jump off buildings and shape his body into a downwards dive (much...

So I've always wondered about how the characteristics of Jets and Props differ. I've always thought of Jets as being low volume high pressure where as props of being high volume low pressure. I have a 750cc Jet ski that uses a water pump impeller as propulsion and it accelerates very quickly...

Hi I'm trying to balance any 3d system with various fixed weights by selecting the correct lift forces for points of lift an example system would be the following shape ( view from above , think a plane missing the right wing) where X is a point of weight and L is a lift point (also has weight)...

Homework Statement a light scale pan is attatched to a vertical inextensible sring. The scale-pan carries two masses A and B. The mass of A is 400g and the mass of B is 600g. A rests on top of B, as shown in the diagram. The scale-pan is raised verticaly, using the string with acceleration...

Hello I am preparing for my aerodynamics exam and I'm having trouble with this question. Why is the Reynolds number of the airflow over a wing important in determining the value of lift and dragThe Reynolds number is important for determining laminar and turbulent flows over a body. It is a...

Homework Statement A platform is supported on a piston by compressed air in a cylinder. The mass of the platform and equipment being lifted is 1100kg. The pressure needed to support this mass is 800kPa, and it rests initially at a height of 0.5m. The pressure supply is closed so that no gas...

Hello Over the past year I've taken up the hobby of RC model airplane flying. During that time I've had many discussions with fellow modelers about lift. I've additionally read a bit about it as well. Most explanations I see like to explain it on Bernoulli's principle. That the wing...

Homework Statement A jet is refueled in mid-air by a tanker. The fueling boom enters the aircraft at an angle of 30 degrees from its flight path. The fuel flow rate is 20kg/s at a velocity of 30m/s with respect to the two aircrafts. The density of the fuel is 700kg/m^3 What is the additional...

Homework Statement A 2598kg airplane is diving (at constant velocity) making an angle of 10 degrees to the horizontal. Find the lift force on the plane assuming that it is normal to the velocity? I think my main problem is the fact that I'm having a bit trouble with understanding the...

Pascal's principle hydraulic lift with torque involved(need help with lever) Homework Statement A hydraulic jack is used to support a mass which has a mass of 30.7 kg. The mass is supported by piston 2 which has a mass of 0.250 kg and an area of 40.2 cm2 . A force is applied by the lever on...

I would like to know how much of a % does Newtons 3rd law (action / reaction) account for lift of a chopper.. i would also like to know this for Bernoulli's principle.. Can you give a source to back it up? I can't find an answer any where

I am a physicist trying to understand the notion of holonomy in principal bundles. I am reading about the horizontal lift of a curve in the base manifold of a principal bundle (or just fiber bundle) to the total space and would like to relate it to the "classic" parallel transport one comes...

Consider a simple prop plane like a Cessna. I'm a little confused about the origin of the energy for lift. We know the engine accounts for all the thrust and the wings have drag that varies by angle of attack, which also changes lift. But does the engine account for all the energy in lift? If...

×Homework Statement A lift cable has mass per unit length 4kg/m. The lift has mass of 920kg (assume that the tension in the cable is provided solely by the weight it supports). When the lift stops at the 3rd floor, the distance from the top of the lift to the top of the cable is 4.6m. Assuming...

This is a simple question hopefully. The equation for determining lift produced by an aircraft is the following if I am correct: L = (1/2) d v2 s CL If I was designing an aircraft that would maintain flight at standard air pressure at 1000 feet .002308 ISA at 130 MPH with a wing area of...

using the following information can anyone tell me if the detailed motor is capable of lifting 90kgs 48" Nominal speed 40 rpm Nominal torque 5 Nm Nominal voltage 12 V Shaft diameter 9 mm Manufacturer part no. DO 111.3761.2B.00 / 3018 Specification DC gear motor Nominal...

I want to create lift of an object about the size of 36 in by 8 in. the lift would be provided by compressed air and the object would have an air dam and skirt (like hovercraft) and lift approx 250 lb mass on it to floatation level of .05 in (where skirt would not reach above lift surface...

A 100g weight resting on a scale took a ride in a lift. From the video clip, determine whether is the lift going up or down based on Newton’s Laws of Motion and sketch the kinematics profile (v-t graph) of the lift carriage. any idea??

I have hydraulic system that lift something heavier than 1 tonne. My problem is the hydraulic fluid always get so hot and sometimes because of the heat it could not lift its load (loss power). I tried to increase its flow rate and its worked for now. But it way above the permitted flow rate...

hello to lift a load of 750kg to a height of 20mtrs at speed of 0.3m/sec, what the horsepower of motor and gear ratio required

Homework Statement Hello guys, I am here and really need your help. In the figure below, the water flow from inlet and then out at outlet with velocity, v = 0.71 m/s. The objective is to calculate find the drag force and lift force act on fishing lure. I have done Ansys Fluent analysis but...

Homework Statement Dear Physics Forums, I was hoping you may be able to help with a problem I am having in my final postgraduate project. A short background of the project to put the problem into context - I am designing and manufacturing a form of powered orthosis to help a person move from...

Homework Statement How many helium-filled balloons would it take to lift a person? Assume the person has a mass of 76 kg and that each helium-filled balloon is spherical with a diameter of 33 cm. Homework Equations P = P0 + ρgV The Attempt at a Solution I really don't know why this is...

Hello I posted something similar to this last week but maybe I was a touch vague as I didn't receive any good answers, So here some more details. I'm looking for the equations required to calculate this and also any variations in the size of the cylinders/distance lifted If I have 2...

Hi I am wondering why a spinning cylinder will produce lift in an inviscid flow. From: http://www.grc.nasa.gov/WWW/k-12/airplane/cyl.html one of the mechanisms for lift generation was the sticking of fluid particles to the wall of the cylinder. I thought that the no slip condition only...

Hi Finding it hard to find exact information on the maths and forces behind this on the internet, (maybe my search terms to blade) If I have a 10cm diamter cylinder that's 10cm deep and filled with water and a piston (weightless piston for the example) at the top and a 1 cm diameter pipe...

I am building a human lift for a vehicle. I am looking a for DC motor able to life 900 ft-lbs with a brake and the shaft is splined. Sending me a link to a company that sells this type of motor would be great. Thank you, Kevin

If rope is wrapped around a pipe and two men are lifting it up why is it easier to lift when the rope is loose around the pipe (A) and harder when the rope is tied tightly to the pipe in a knot at both ends (B) ? I presumed this was because on A the weight is less concentrated?

Homework Statement What is the lift (in Newtons) due to Bernoulli's principle on a wing of area 89 if the air passes over the top and bottom surfaces at speeds of 260 and 160 , respectively? The Attempt at a Solution[B] um...i understand that the higher velocity of the air above the...

Homework Statement The tension in the cable supporting a lift moving upward is twice the tension when the lift moves downward. What is the acceleration of the lift? Homework Equations The Attempt at a Solution i think its only conceptual but still please show me the way how to...

I understand how an aeroplane works, with the wings deflecting air downward and thus creating a lift force. I understand how a helicopter works, with the rotor pushing air downward and thus creating a lift force. However, I do not understand how gyroplanes, with a backward-tilted unpowered...

I am running ANSYS fluent simulation flow over naca 0012 airfoil. So far the lift coefficient is similar with the published papers. The problem is drag coefficient is different so much in term of value compared to published papers. I have check my mesh quality and boundary condition, it shows...

1. What is the lift force on the roof of your car that has an area of 3.9m^2 if you are driving 100km/hr? use 1.17kg/m^3 for density of air. im not even sure where to start. have never done this.

the question I am stumped on is "What is the lift force on the roof of your car that has an aera of 3.9m^2 if you are driving 100km/hr? use 1.17kg/m^3 for density of air

Actually i am using lead screw drive by motor along with rope drive. If you will see the attachment, yuo can clearly understand the working principle. In this working priniciple, when we used to start the motor, carriage power use to go up through lead screw drive.Rope is connected to this...

Homework Statement http://data.imagup.com/10/1146555432.jpg Homework Equations Force applied on the weight=F*(MA). The Attempt at a Solution i chosse the E system ...it has the greater mechanical advantage (MA)=3. MA(of A)=1, MA(of B)=2,MA(C)=2,MA(D)=2,MA(E)=3.. I hope my...

I want to design a RC helicopter powered by a gas engine. The total mass to be lifted by the helicopter is 25 to 30 Kg. What is the engine power or engine size (in cc) required to lift the helicopter? Can someone please provide me some calculation? Regards

Dear Experts I like Hydraulic mechanisms as it can be used to lift heavy things with little force. I like to find out more about it. 1. How is leaking prevented ? Fluid is used to transfer the energy. For example, oil. It is so fine, how can the oil not ooze from the piston-cylinder...

Hi - am looking for some data points on how much suction is required to lift an object at different weights and volumes. Especially interested in any data relative to displacing an object caught in the throat if you are choking. Appreciate any help!

Homework Statement The problem: There is an illustration and the question is to find the force F to lift a concrete block gate if the the concrete weighs 160 lb/ft3. The block is 3' in diameter and 1' thick. It is in a tank of fresh water 15 ft down. the specific weight of the fresh water...

Elevator design -no electricity supply? I hope someone can help me. I'm designing a building for uni that requires several lifts (elevators) which transfer bicycles and pallets vertically. My tutor suggested to look at energy efficient lifts. He mentioned that he had seen a lift, which...

says that the pressure is distributed evenly around a fluid. What I'm having a hard time understanding is the hydraulic lift, so I thought I would think of a simple system that could represent a fluid and then use that for intuition. Regrettably I did not get the same conclusions with that...