Purchase Solution

Questions on Center of mass, Torque and Levers

Not what you're looking for?

Ask Custom Question

Please refer to the attachment for the mentioned figures.

1. Three masses, 2.0 kg, 3.0 kg, and 6.0 kg, are located at points (3.0, 0), (6.0, 0), and (-4.0, 0), respectively, in meters from the origin. Where is the center of mass of this system?

2. A dumbbell, Figure below, has a connecting bar of negligible mass. Find the location of the center of mass
a. if m1 and m2 are each 5.0 kg, and
b. if m1 is 5.0 kg and m2 is 10.0 kg.

3. A water molecule consists of an oxygen atom and two hydrogen atoms. Oxygen has a mass of 16 atomic units (u) and each hydrogen has a mass of 1 u. The hydrogen atoms are each at an average distance of 96 pm ( 96 x 10^-12 m) from the oxygen atom, and are separated from one another by an angle of 104.5 degree. Find the center of mass of a water molecule.

4. Two children are balanced on a see-saw of negligible mass. (This assumption is made to keep the example simple.) The first child, sitting on left side of the pivot, has a mass of 26.0 kg and sits 1.60 m from the pivot. The second child, sitting on right side of pivot, has a mass of 32.0 kg and 1.3 m from the pivot. Calculate the position of center of mass of the two children:
a. from the first child
b. from the pivot point.

5. Three balls A, B, and C, with masses of 3 kg, 1 kg, and 1 kg, respectively, are connected by massless rods. The balls are located as in Figure below. What are the coordinates of the center of mass?

6. Alley club-ax consists of a symmetrical 8 kg stone attached to the end of a uniform 2.5 kg stick that is 98 cm long. The dimensions of the club-ax are shown in Figure blow. How far is the center of mass from the handle end of the club-ax?

7. A 46.4 N force is applied to the outer edge of a door of width 1.26 m in such a way that it acts
a. Perpendicular to the door.
b. At the angle of 43.0 degree with respect to the door surface.
c. So that the line of action of the force passes through the axis of the door hinges.
Find the torque for these three cases.

8. When opening a door, you push on it perpendicularly with a force of 55.0 N at a distance of 0.85 m from the hinges. What torque are you exerting relative to the hinge?

9. If the load placed in the wheel barrow weighs 20 N and is 40 cm from the wheel, what force must be applied to the handles at a distance of 120 cm in order to balance the load?

10. A child of mass 40.0 kg is sitting on a horizontal see-saw at a distance of 2.0 m from the supporting axis. What is the magnitude of the torque about the axis due to the weight of the child?

11. In figure below, a force with a magnitude of F = 55 N is applied to a door; however the lever arms are different in the three cases a, b, and c. Take the distance between the hinge (black dot) and the door knob as 0.8 m, and in case b take lever arm as 0.6 m. Find the torque in each case.

12. Figure below shows the ankle joint and the Achilles tendon attached to the heel at point P. The tendon exerts a force F with a magnitude of F = 720 N . Determine the torque (magnitude and direction) of this force about the joint, which is located 3.6 x 10^−2 m away from point P.

Attachments
Purchase this Solution
Solution Summary

This posting contains the solution to the given problems.

Purchase this Solution
Free BrainMass Quizzes
Basic Physics

This quiz will test your knowledge about basic Physics.

Classical Mechanics

This quiz is designed to test and improve your knowledge on Classical Mechanics.

Introduction to Nanotechnology/Nanomaterials

This quiz is for any area of science. Test yourself to see what knowledge of nanotechnology you have. This content will also make you familiar with basic concepts of nanotechnology.

Variables in Science Experiments

How well do you understand variables? Test your knowledge of independent (manipulated), dependent (responding), and controlled variables with this 10 question quiz.

Intro to the Physics Waves

Some short-answer questions involving the basic vocabulary of string, sound, and water waves.

View More Free Quizzes
Related BrainMass Solutions

  • Constant Angular Momentum

    The torque applied by a force on the disk is given by: Where d is the distance of the force point of application to the axis of rotation (the lever) and  is the angle between the force and the lever.

  • Levers

    Thus torque= E shin X R knee-shin -----------------(C) Thus in the case of two third class levers the torque=B+C CONCLUSION As we have shown B= A (Assuming effort applied by the thigh muscles is the same) Thus in the case of two levers working together

  • Physics Lab experiment on Static Equilibrium

    Ideally this should be zero for a balanced yardstick Q1: Torque with respect to the center of mass, m1 a 1 - m2 a2 = 0 where m1 and m2 are weights (in Newton) hanged at a distance of a1 and a2 from the center of mass.

  • moment of inertia about center of mass and torque applied

    189056 They rotate about the center of mass See the attached problem below. A 0.9 kg mass at (x, y) = (20 cm, 20 cm) and a 2.6 kg mass at (20 cm, 100 cm) are connected by a massless, rigid rod. They rotate about the center of mass.

  • Torque, Equilibrium, and Stability

    If the mass of the board is 15 kg, how close to the end can the painter stand without tipping the board over? Torque of board from scaffolding: Center of board is center of mass which is 1.25m from scaffolding.

  • Sample questions are demonstrated.

    The moment of inertia about the center of mass of an 60 kg object is 1.4 kgm^2. If the moment of inertia about the object's proximal end is 40 kgm^2, what is the distance between the proximal end and the center of mass? 9.

  • Torque Function Defined

    But while torque is usually applied to rigid bodies, such as wheels and levers, it does not have to be. The concept of torque can be applied to any body with respect to a fixed point in space.

  • Physical quantities of system of particlaes

    The total energy of the system is simply: The position of the center of mass is: And the speed of the center of mass is: Thus, the translational energy is: The rotational energy is the difference between the total energy and

  • Physics - Questions on Momentum

    226844 Momentum questions are embedded. 1. If a person pushed on a door with a force of 650 N and a moment arm of 0.75 meters, what would be the moment created? 2.

View More Related Solutions