Lift Definition and 614 Threads

I'm not a maths person, so bear with me, but I'm trying to prove that with 3.5kW you could lift the average american male (89kg) to a height (take just as displacement) of 3 storeys (about 9.14 meters) in under 3 seconds. Is somebody able to calculate this for me? Thanks!

Homework Statement The mass of a space shuttle is approximately 2.0 x10^6 kg. If the thrust provides a force of 1.2 x 10^7 N, what is the acceleration of the space shuttle at lift off? 6.0 m/s2 0.06 m/s2 1.67 m/s2 0.167 m/s2 Homework Equations Resultant force = thrust – weight Acceleration =...

How can I find an equation to calculate the lift coefficient on a basketball at different launch velocities? I looked at different papers explaining the physics of basketball throws but all i could find was an equation for the drag coefficient: -mv +1/2 ρ A Cd v^2 = mv

I have been thinking about the CoL and CoT on rockets. I came to the conclusion that they are in the exact same spot on the rocket since your thrust and lift come from the same thing in the same place, the engine. I read some forums on other websites but didn't get a clear answer. It would be...

Homework Statement A student investigates the efficiency of a small electric motor. He uses a motor to lift it a mass through a constant distance of 1 m. He times how long it takes to lift the masses and makes a record of the potential difference and the current of the motor. In the book that...

Hi All, I'm hoping to work on deriving the governing fluid flow equations for a frisbee in flight theoretically and then to test it on a wind tunnel, and compare results. If u could please help on how do i apply/derive the necessary equations. Respectful Regards

Firstly, I'm new to these forums, and I'm not sure what the prefixe in creating this thread is supposed to be... (i'm assuming it is to judge to question's level)? saw some threads without prefixes but i can't post one without... maybe i missed a stickied thread or a readme? Alright, so, first...

Homework Statement Homework Equations P=Fv The Attempt at a Solution Since the elevator is rising at a steady speed, a=0, thus, the tension on the string equals to the weight of the elevator. I chose C as I thought just for the elevator case, it would be m1gv, but how does m2 affects the...

Wings generate lift because of the curved shape of the top wing air flow faster over the top and sucked up the plane. This would be bad for a fighter jet flying upside down. Wright brothers plane wings are flat so the wing must be deflected down. So curved wings are just aerodynamic. Soo which...

We all know the lift force in case 1, what about case 2 ?

I would much appreciate any critique to this line of thinking. Draw a circle around the airplane to see it as a free body diagram. The airplane engine provides horizontal force to move the plane. Force (F=ma) is a vector quantity with a horizontal direction. The wing lift is a force in the...

Homework Statement A 15000-kg helicopter is lowering a 4000-kg truck by a cable of fixed length. The truck, helicopter, and cable are descending at 15.0 m/s and must be slowed to 5.00 m/s in the next 50.0 m of descent to prevent damaging the truck. Assume a constant rate of slowing. Determine...

Homework Statement Homework Equations Concept of couple? The Attempt at a Solution First, I calculated the couple about disc, though I'm not sure if I can use this approach. Since 900 N is pulling the string of pulley downwards, I take the couple about disc as 900 x 0.4, which gives me 360...

I am a little confused about the work do the to lift an object. I know that in lifting an object a net force must be applied in order to increase its velocity, but when the object stops, gravity applies an equal but opposite force, which means that in lifting an object no net work on the object...

Hi, I read several approach to the explanation of aerodynamic lift. Bernoulli, Newton, Kutta-Joukowski. I found a topic about discussing Bernoulli and Newton, and the conclusion was that they are both valid individually. But what about the Kuttaa-Joukowski theorem? And are these approaches all...

I'm a little afraid to ask something that should be such a basic question, yet there seems to be an enormous discrepency in-between theory and reality, here. In many, many problems I've worked with "find the work to lift X", you simply take the change in potential energy. When lifting Mass m by...

Hi Everyone, not sure why it is so difficult to find any info on how to build a simple electromagnet with diagrams or plans... but it is! I need to lift sheet plate... thousand poinds or more... something like a 2 car battery design electromagnet for lifting... Please, Please, don't tell me I...

Hi all,I would like to know how to calculate the force required to lift a flap (or drawbridge if you proffer) of known weight that is on a pivot and where the pull chain (let’s say it’s a chain) connects to the flap at a known distance from the pivot.I’d also like to be able to calculate the...

What would it take for this to lift a man? Hi, as an inventor i am interested to know what it would take to make one of these ideas lift someone into the air? Let's imagine that it is made of graphene covered carbonado mesh frame, such that it is very light. As for power, let's use a rotory...

Hello, I work for a company specialized in building van bodies. The problem is our engineer left and I know nothing about pneumatics. The customer's requirement is to be able to raise and lower the roof by up to 1 m. The box bodies are 7-8 meters long, so I think 6-8 pneumatic cylinders will...

Homework Statement From a lift moving upward with a uniform acceleration 'a', a man throws a ball vertically upward with a velocity v relative to the lift.The ball comes back to the man after a time 't' Show that a+g = 2v/t Homework Equations s=ut+1/2gt2 The Attempt at a Solution I know this...

I am in Austria on a walking holiday, Why are the pylons on ski lift's not vertical? I only have A level physics but surely centre of gravity and gravitational force must put tremendous pressure on the back of the pylon, as it will naturally want to lean fwd. My friend says this is just good...

I http://www.pentalift.com/lift-tables/scissor-lifts&multi-stage.php. It works fine, when a single person is in the lift, but when 2 people of average weight are in the lift it will not go up properly. We haven’t exceeded the rated maximum capacity of the lift platform. It seems like it does not...

I know from physics 101 that f = ma. And if I want to lift an object straight up i have to multiply its mass times gravity (acceleration) and I get the force I need to require to overcome it. But what about lifting your body out of bed? Just the part where you physically get up from the lying...

opposites magnetic fields repel each others. How big of an magnetic would I need to lift mass ( 5g) 3 centimetre in the air. F = MA A = 9.81 m/s^2 M = mass of the object ( 5 g) F = 49.05 F = I L x B 49.05 = IL X B I = 3000 mA ( from a AA battery) µ = 4π E-7 T m/A Bsol = µ N/L I F = IL X...

How we can incorporate valve lift and variable flow rate in compressed air engine Mechanical power = air power torque * angular velocity = pressure * flow rate

Hi, here i need to calculate the tilt angle of the scissor lift. I had done some reviews for designing a scissor lifter, some source state that, tip-over will happen only when the kinetic energy of the system is less than the Potential energy after impact. Hence, i was trying to use this...

Homework Statement Please see attached for diagram. We know that the elevator arm is horizontal when the lift is stationary, with ## M_{1}=\frac{4M_{2}M_{3}}{(M_{2}+M_{3})}## It wants us to find out if this is still the case when the lift is accelerated upwards at a constant velocity ##g##...

What size propeller is required to lift a 180 lb person 30ft into the air consistently? Also, how powerful would the motor have to be to lift itself, the propeller, and person?

I'm confused about how an airplane generates lift. If I'm correct the wing of the plane is bent so air can flow over the top of the wing faster than the bottom of the wing, the faster fluids somehow apply less pressure resulting in a net upward force. Why though does a bent wing allow air to...

Homework Statement This is a 'random discussion' that I had today with a student; it is not out of a textbook, nor does the solution carry any weight at all (pls excuse pun).[/B] A simple pendulum is happily swinging back and forth attached to a pin in the wall of the lift, where the pin is...

So my question is, if a laithwaite engine (my attached photo) spins fast enough, will it be able to lift off the ground? And if yes, what's the maths to calculate the speed needed to make it lift?

Homework Statement A rectangular box is being pulled by a rope with a force T on a horizontal surface, with a friction coefficient μ. What is the minimum angle α at which it will lift of the surface? See attached image. Homework Equations \begin{equation*} \tau = rF\sin\alpha \end{equation*}...

Homework Statement A pump is required to lift 800 kg of water (about 210 gallons) per minute from a well 14.0 m deep and eject it with a speed of 18 m/s (a) How much work is done per minute in lifting the water? (b) How much work is done in giving the water the kinetic energy it has when...

I am trying to calculate the force required to close the valve on an annular bop. A rubber ring (called a packing unit) closes around the pipe when a force is applied from underneath, as shown here. The actual valve has the hydraulic fluid coming into a chamber that goes the around the outside...

Good day Geniuses. im building a drone prototype for an agricultural project. approx. weight will be 600 lbs, using my own 8 rotor design. trying to determine rotor size and motor power required to fly such a device at 30 feet. would also be interested to determine an approximate wind speed...

Hello everyone! I am interested in roughly calculating the lift from an airfoil that has air circulating around its full circumference, (can be done by a treadmill skin but probably best done in practice by blowing air from slots around the entire circumference as seen in Fig.1) As...

Hi, I need to design a lift mechanism that is powered by a small continuous servo. It needs to lift a plate up at least 4 inches, and be totally powered by this servo...

Hello guys I want to fabricate hydraulically operated scissors lift. I preformed calculations & fabricated same but unfortunately it didn't work. Can anybody help me out to design it again. Required specifications are Maximum load: 1000Kg Open height: 1500mm Closed height: less than 375 mm...

Hey everyone, I'm a student working on building a wind tunnel with some classmates. I'm in charge of figuring out the drag and lift force sensors. I'm currently looking these two components: http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2128260_-1...

Homework Statement A crane lifts a load of 3000 kg to a height of 8.5 meters in 15 seconds. Calculate the lift work? Homework EquationsThe Attempt at a Solution This is a very simple problem but the thing is its unclear data. The given data does not clarify whether or not this is an...

Hello, I need help regarding calculating the lift force for a hovercraft. I found an equations online on thrust propulsion. Equation → T= π/4 x D^2 x (v + Δv/2) x ρ x Δv D- diameter of propeller v- velocity of incoming flow Δv- additional velocity, accelerated by propeller ρ- density of air...

Homework Statement A lift ascends from rest with uniform acceleration of 4m/s², then it moves with uniform velocity and finally comes to rest with uniform retardation of 4m/s². If the total distance covered during ascending by the lift is 28m and the total time for ascending 8s respectively...

Hello all, Yet another problem on engineering mechanics. This time I have a spring loaded; counterpoised arm: Something like this- http://www.akwmedical.com/files/imagecache/cart/SK2323_1.jpg http://t3.gstatic.com/images?q=tbn:ANd9GcTUCvnSKhKEbs4uNiOLg2TGU3p0quUrSp8Uh4QXqt5m4eIEf6_ISA What it...

I have a few questions related to downforce in cars. Please forgive any fundamental misunderstanding of aerodynamics. Does the shape of a car, say a Volkswagen Golf, driving on a road produce lift or downforce? Is the Coanda Effect at play there? How does the height of the car above the ground...

we all have heard about this conundrum,about the bees can't fly because of the whole small surface area of the wings and greater weight than the lift achieved thing.However,there were some articles that I read that this question had been solved, that bees don't flap their wings up and down, they...

Suppose there are 2 sets of magnets housed inside a box.One set can move vertically and the other set moves horizontally.Now if enough repulsion is created between the vertical set's magnets the top magnet will touch the box's body and try to go out but can't.So if I keep the repulsion going...

Been working on a new way of determining the lift coefficient besides the thin airfoil theory,and I don't know if there is already such a method or if I'm wrong.Plz Help.We know, L=CL×1/2ρv^2A Now,as lift is a force,then it should be as L=mμ, where μ is the "upwards acceleration". So...

Can I convert an electric log spliter and use the hydrolic to create a dump lift? Using my truck and its 12 volt battery

Hi guys, I'm working on a project for school and I have measured the influence of the angle of attack, the wingspan and the speed of the air on the lift force the wing is producing. Now I have the question what these data say about real wings from planes. I've already red it has something to do...