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tensions in the strings and accelerations of the object

Please see the attached file. An object of mass m1 on a frictionless horizontal table is connected to an object of mass m2 through a very light pulley P1 and a light fixed pulley P2 as shown below. (a) If a1 and a2 are the accelerations of m1 and m2, respectively, what is the relation between these accelerations? (

3 good questions in mechanics: Force, work and energy.

Please see the attached file for full problem description. 1.) To immobilize a fractured femur, doctors often utilize the Russell traction system illustrated in the figure below. Notice that one force is applied directly to the knee, F1, while two other forces, F2 and F3, are applied to the foot. The latter two forces combine

Simple Machines: Force required to push a box up a ramp.

1. A 400-lb piano on frictionless casters is to be pushed up a 20 ft ramp to a loading platform 3 ft above the ground. How much force is needed? 2. A block weighing 250 lbs is to be raised into a wagon 30 in high by a boy who can only exert a force of 50 lbs. (a) what is the shortest board he must use as an inclined plane wh

Dynamics: Block attached to spring on incline with friction

4. A Constant force F is applied to a body of weight W resting on an inclined surface which the coefficient of friction is The body is restrained by a spring having a spring constant of K. Compute the velocity of the body in terms of F and other parameters that are given when the body has moved from rest a distance up the inclin

Find Fmax

Please see the attached document. A 650 g particle moving along the x-axis experiences the force shown in Figure Ex11.15. The particle goes from vx = 3.0 m/s at x = 0 m to vx = 4.5 m/s at x = 2 m. What is Fmax?

Impulse and force

During a violent thunderstorm, hail of diameter 1.0 cm falls directly downward at speed of 25m/s. There are estimated to be 120 hailstones per cubic meter of air. (a) What is the mass of each hailstone (density = 0.92 g/cm^3)? (b) Assuming that the hail does not bounce, find the magnitude of the average force on a flat roof mea

Photoelectric Effect: Energy of photoelectrons emitted.

Light from a laser hits the surface of cesium. With a minimum photon energy of 2.14eV being required to remove photons. When the surface of cesium is illuminated with this light photoelectrons are emitted with a max kinetic energy of 0.76eV. Assuming that the Planck constant is 4.14x10^-15 eV Hz-1. What would be the energy of

Work & Power

Work & Power - Involves you walking up a flight of stairs and recording your time via a stopwatch or chronograph.You will be asked to make measurements and calculations for the total time to walk the flight of stairs (at least 7 steps) and the vertical height of the stairs from the bottom to the top. o Estimate your mass in kg

Atwood's Machine

In a simulation, m1 is 1.0 kg and m2 is 1.1 kg. Mass m2 rests on the floor that exerts a normal force, FN, on m2. There is no motion (i.e.. the system is in equilibrium). What is the normal force, FN, and what is the tension, T, in the rope? T (at t = 2.54 s) = ______. At equilibrium: FN + T - m2 ? g = 0. Then FN = _______.

Particles and Waves

1.) In a television picture tube the electrons are accelerated from rest through a potential difference V. Just before an electron strikes the screen, its de Broglie wavelength is 0.8*10^-11 m. What is the potential difference? 2.) A photon has the same momentum as an electron moving with a speed of 1.6 *10^5 m/s. What is t

Energy and work

Please see attachment. 12. A rock is thrown straight up from the surface of the Earth. Which one of the following statements describes the energy transformation of the rock as it rises? Neglect air resistance. 13. A helicopter is cruising at a speed of 25.0 m/s at an altitude of 185 m. What is the total mechanical energy of

Rolling Ball

In a lab experiment you let a uniform ball roll down a curved track. The ball starts from rest and rolls without slipping. While on the track, the ball descends a vertical distance h. The lower end of the track is horizontal and extends over the edge of the lab table; the ball leaves the track traveling horizontally. While free

average thermal power

A 10.0 kg rock slides on a rough horizontal surface at 6.50m/s and eventually stops due to friction. The coefficient of kinetic friction between the rock and the surface is 0.300. What average thermal power is produced as the rock stops?

Swing - Potential energy, speed etc.

A 23.0 kg child plays on a swing having support ropes that are 1.90 m long. A friend pulls her back until the ropes are 39.0 (degrees) from the vertical and releases her from rest. Part a: What is the potential energy for the child just as she is released, compared with the potential energy at the bottom of the swing? V=

Work done by earth on moon and by sun on earth.

Assume that the earth and the moon have circular orbits (which is almost true) and that the periods of their orbits are 365 days and 28.0 days, respectively How much work does the earth do on the moon in one day? W(earth)= ? J How much work does the sun do on the earth in one month? W(sun)= ?J

Energy, Momentum and Projectile Motion

please include all diagrams and calculations and assumptions The object of a pinball game is to project the "particle" (the red ball) so that it enters the hole at E. When the spring is compressed and then released the particle is projected along the track which is smooth except for a rough patch between a and b where the c

Work done on a cutting tool.

A cutting tool under microprocessor control has several forces acting on it. One force is F = -alpha xy^{2} hat{ j }, a force in the negative y-direction whose magnitude depends on the position of the tool. The constant is alpha = 2.25 N/m^3. Consider the displacement of the tool from the origin to the point x = 2.10 m, y = 2.

Amount of work to accelerate

Suppose I put in 10keV (1eV = 1.6 x10-19J; 1keV = 103eV) of work to accelerate an electron (rest mass = 9.1x10-31 kg). With this amount of work, up to what speed (in terms of c) can the electron be accelerated if it starts from rest?

Energy Stored in a Spring

The force exerted by an unusual spring when it is compressed a distance x from equilibrium is given by F = -kx-cx^3, where k=220 N/m and c=3.6 N/m^3. Find the energy stored in this spring when it has been compressed by 15 cm.

Magnitude of a Force

A 5.0 kg object moving on a horizontal surface has an initial velocity, vi=(5.0i+10.0j) when a force F acts on the object for 3 seconds after which velocity is vf=(10i+30j) m/s. Determine the work done by the force F on the object. What is the magnitude of the force F?

angular velocity of the particle and work done

A particle of mass m is moving on a frictionless horizontal table and is attached to a massless string, whose other end passes through a hole in the table, where I'm holding it. Initially, the particle is moving in a circle of radius r0 with angular velocity w0, but I now pull the string down through the whole until at length r