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Equilibrium

Physics (solving for optimal diameter of rope to support given weight)

An artist friend of yours needs help hanging a 500 lb sculpture from the ceiling. For artistic reasons, she wants to use just two ropes. One will be 30 degrees from vertical, the other 60 degrees. She needs you to determine the smallest diameter rope that can safely support this expensive piece of art. On a visit to the hardware

Submerged Block

A beaker contains a thick layer of oil floating on water. A cubical block of wood is gently lowered into the beaker, so as not to disturb the layers of liquid, until it floats peacefully between the layers, as shown. a) What is the distance between the top of the wood cube (after it has come to rest) and the interface between

Walking the Plank

Please do not place your response in a .pdf format, but Word documents are okay. Thanks! A horizontal uniform bar of mass m and length L is hung horizontally on two vertical strings. String 1 is attached to the end of the bar and string 2 is attached a distance L/4 from the other end. A monkey of mass m/2 walks from one end o

Translational Equilibrium

A leg and cast weighs 220 N (w1) The leg held in traction by two weights (w2 and w3) attached to strings and applies in order that there be no force exerted on the hip joint J by the leg in the cast. (In other words the leg is in translational equilibrium) what are the numerical values of w2 and a for this to happen if w3=110 N?

Universal Gravitation

At what distance from the Earth will a spacecraft on the way to the moon experience zero net force due to these two bodies because the Earth and moon pull with equal and opposite forces? Thanks

Vector polygon to solve for the forces on a block in equilibrium on a plane.

A block whose weight is W= 250 nt is on a frictionless plane which is at angle q= 25 degrees. A cable between the ceiling and the block makes an angle q=55 degrees from the ceiling. See ATTACHMENT1 for a diagram with given parameters, angles, physics statements, and a polygon created from known information. Also an illustration

A spring and its force constant

A spring whose force constant k= 84 nt/m is suspended by one end from a support. The unstressed spring's length is .66 m. Find the length of the spring when a mass of M= 12 kg is suspended from the lower end, in equilibrium.

SHM of a mass hanging from a spring.

A certain spring with its upper end attached to a ceiling and nothing attached to its lower end has a length s= .6 m. When a mass M= 2.0 kg is attached to hang from its lower end the spring then has a length h= .80 m. See ATTACHMENT for a diagram showing parameters. The mass is raised .15 m above equilibrium point and releas

Equilibrium Conditions

A container is partitioned by a porous, fixed, wall. Because the wall is porous, it allows particles to diffusive from one side to the other (note that by 'diffuse' I mean that there are tiny holes in the wall which allow the gas particles to make it through; there is not some big gaping hole). The wall also allows the flow of

Speed of Blocks on an Incline

A block, mass = m1, lies on an incline of angle theta, and is connected to a second block of mass m2=3/2 m by a string that passes over a light frictionless pulley. The second block hangs vertically and is firmly attached to a spring that has negligible mass and a force constant of k. The opposite end of the spring is firmly a

Equilibrium/torque

Hi. I need some help with a conceptual question. "A uniform 1-meter stick that is supported by a fulcrum at the 25-cm mark is in equilibrium when a 1-kg rock is suspended at the 0 cm end. Is the mass of the meter stick greater than, equal to, or less than the mass of the rock?" I thought the answer would be that the mass o

Buoyant force on an object submerged in a liquid in equilibrium.

See attached file. To hold up a certain stationary iron anchor in air takes 200 newtons more than when it is submerged in fresh water. The density of iron is Di=7870 kg/m^3, and by definition, the density of fresh water is Dw=1000 kg/m^3. Find the weight W, of the anchor in air.

Torques in equilibrium on a leaning ladder.

A uniform bar of length L= 8 m, whose weight is 420 nt is placed into a totally frictionless, open top box in the shape of a cube whose sides are length s= 4m. Its bottom end is at a lower corner and it extends over the opposite top edge. See ATTACHMENT for a diagram with dimensions. Find P, the force the top edge exerts again

Torques on a boom in equilibrium.

A uniform boom is at an angle of 45 degrees from the ground. It is held in place by a frictionless pin at ground level. Weight A= 2230 nt is suspended from its upper end and the boom's weight B= 441 nt. A cable from its upper end to ground level makes angle 30 degrees with the ground. See ATTACHMENT for a diagram. Find T, the t

A door in equilibrium requiring application of net torque equal to zero.

A uniform, rectangular door 2.2 m high and 2.4 m wide having a weight of 260 nt is supported by two hinges. One hinge is .30 m from the top corner and the other is .30 m from the bottom corner. Each hinge supports half the total weight of the door. See door ATTACHMENT for a diagram. Find the magnitude of the total force exert

Heat

A pan of water is heated from 23 C to 78 C. What is the change in its temperature on the kelvin and fahrenheit scales? A 0.225 kg sample of tin initially at 97.5 C is dropped into 0.115 kg of water initially at 10.0 C. If the specific heat capacity of tin is 230 J/kg *C (its a dot before "C" but im not exactly sure how t

Spring supporting two blocks without friction

A 0.7 lb block rests on top of a 0.5 lb block supported by but not attached to a spring of constant 9 lb/ft. The upper block is sudenly removed. A) Determine the maximum velocity reached by the 0.5 lb mass B) the maximum height reached by the 0.5 lb mass Please see attachment

Rotational equilibrium

I am trying to help my brother (in high school) understand how to solve rotational equilibrium problems. What he needs is an explanation on how to approach these problems. I understand each problem is different, but I imagine there must be a general method for solving them. I have put a problem below so that hopefully you could

Rigid Objects in Equilibrium, Center of Gravity

A lunch tray is being held in one hand. The mass of the tray itself is 0.200 kg, and its center of gravity is located at its geometrical center. On the tray is a 1.00-kg plate of food and a 0.250-kg cup of coffee. Obtain the force T exerted by the thumb and the force F exerted by the four fingers, Both forces act perpendicular t

Tension - Equilibrium and Elasticity: Five problems

The graphs are attached in word document. 1. The system in the picture is in equilibruim with the string in the center exactly horizontal. Find (a) tension T 1 , (b) tension T 2 (c) tension T 3 (d) angel pheta 2. The system in the picture is in equilibrium. A concrete block of mass 225 kg hanfs from the end of the unif

Fluid Mechanics: bouyance, harmonic motion, period

Consider an object with height h, mass M, and uniform cross sectional area A floating upright in a liquid with density p. a.) Calculate the vertical distance from the surface of the liquid to the bottom of the floating object at equilibrium. b.) A downward force of magnitude F is applied to the top of the object. At the

Speed of object in revolutions around a circle: puck of mass tied to a string

A puck of mass 0.270 kg is tied to a string and allowed to revolve in a circle of radius 1.09 m on a frictionless horizontal table. The other end of the string passes through a hole in the center of the table, and a mass of 1.24 kg is tied to it (see figure in attached Word file). The suspended mass remains in equilibrium while