Work done by and against a force - Physics Forums
Jan 8, 2016 · There are two forces acting on the box: gravity and the force exerted by you. The work done by gravity (as you well know) is -mgh; the work done by you, which you could think of as work done 'against gravity' is mgh. But when work is involved, there is always something exerting a force on something else. Jan 8, 2016.
Calculating Work Done by Impulsive Force - Physics Forums
Oct 24, 2014 · Calculating Work Done by Impulsive Force. In summary, the applied force exerts an impulse J on a particle, changing its speed from u to 2u. The force and initial velocity are in opposite directions along the same line. The work done by the force is Ju/2. To find this, the change in kinetic energy can be expressed in terms of momentum and ...
Work Done on Object When Net Force is Zero - Physics Forums
Jul 7, 2012 · The concept of work done on an object when the net force is zero is that when the net force acting on an object is zero, there is no change in the object's velocity and therefore no work is done on the object. This means that the object does not move and there is no transfer of energy to or from the object. 2.
Work Done by Crane: Calculating Force & Acceleration - Physics …
Apr 8, 2016 · The units for work done and force are both in Newton-meters (Nm) or Joules (J). 5. How does the height of the crane affect the work done? The height of the crane does not affect the work done, as long as the distance the object is lifted remains the same. The work done is only affected by the force applied and the distance the object is lifted ...
How Is Work Calculated When Lifting an Object with a Tension …
Apr 9, 2005 · In summary, the work done by the tension force is calculated by adding the product of the mass and acceleration of the object to the product of the mass and gravitational force, and then multiplying that sum by the distance the object was pulled upward. In this case, the work done is 5500 joules. Apr 9, 2005. #1.
Is Work Done While Walking Without External Force Applied?
Jan 3, 2007. Work Work done. In summary, while walking, some work is done by our body if no external force is applied on our body. However, this work is less efficient than when the body is moving due to the fact that a larger percentage of our leg motions are not propelling us forward. Additionally, swinging the arms while walking does not ...
Work done by spring force and by gravity? - Physics Forums
Jul 12, 2011 · Setting the potential reference level of zero at the unstretched point of the spring (x=0), Work done by gravity: W = m*g*x. Work done by spring: W = -1/2 * k * x^2. Equating the equations to each other at equilibrium where the net force is zero, we get: 2 * m * g = -k * x.
What is Work Done? Definition, Equations, & Explanation - Physics …
Jul 24, 2014 · Work Work done. In summary, work is a measure of change of energy and is equal to the integral of the dot product of force and displacement. The SI unit for work is the joule (J) and for power is the watt (W). Work can also be described in terms of conservative forces and potential energy, and can be used to determine gearing in a system.
How Much Work and Force Are Involved in Marathon Running?
Aug 14, 2010 · The calculation of work done during running involves multiplying the force applied to the body by the distance covered. This force can be measured by the weight of the body and the resistance of the surface being run on. The distance …
Work done = force x displacement? - Physics Forums
Jul 12, 2014 · Yes, work done can be negative. This happens when the force applied and the displacement are in opposite directions. In this case, the work done is considered to be negative because the force is acting against the motion of the object, resulting in a decrease in its energy.