PHYS 2101 : Practicetest 2

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azuremammoth471

15 Mar 2019

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The force is in units of newtons and the positions are measured in meters. The mass is pulled to the right a distance x = 0. 2 m and then released. What is the total mechanical energy of the spring-mass system when the mass reaches x = 0. 1 m. (a) zero (b) 1 j (c) 4 j (d) 7 j (e) 9. 8 j: show your work on this problem. A mass m is attached to a massless rod of length l, which can pivot about one end so as to rotate in a vertical circle, as shown below. The mass is given an intial velocity vo. A 150 kg defensive lineman runs at 5. 0 m/s along the platform (parallel to the track) and then jumps onto the flatcar. The other end of the spring is fixed to a wall. Block 1 (mass 2. 5 kg), traveling at speed v1 = 4. 0 m/s, undergoes a completely elastic collision with block 2.

Related Questions

At the instant the displacement of a 2.00 kg object relative to theorigin is d = (2.00 m)i + (4.00 m)j - (3.00 m)k, its velocity is v= (6.99 m/s)i + (3.66 m/s)j + (8.14 m/s)k and it is subject to aforce F = (9.02 N)i - (3.34 N)j + (9.52 N)k. Find the accelerationof the object ((a), (b) and (c) for i, j and k componentsrespectively), the angular momentum of the object about the origin((d), (e) and (f) for i, j and k components respectively), thetorque about the origin acting on the object ((g), (h) and (i) fori, j and k components respectively), and (j) the angle between thevelocity of the object and the force acting on the object.

A 15 kg object is acted on by a conservative force given by F =-1.7x - 4.7x2, with F in newtons and x in meters. Take thepotential energy associated with the force to be zero when theobject is at x = 0. (a) What is the potential energy of the systemassociated with the force when the object is at x = 2.3 m? (b) Ifthe object has a velocity of 2.9 m/s in the negative direction ofthe x axis when it is at x = 6.3 m, what is its speed when itpasses through the origin? What are the answers to (c) (a) and (d)(b) if the potential energy of the system is taken to be -12 J whenthe object is at x = 0?

The work done in pushing a TV set a distance of 2 m with an average force of 20 N is
(A) 2 J.

(B) 10 J.

(D) 40 J.

(E) 800 J.