Answer:
5..No work is being done.
Explanation:
Hello!
Remember that the concept of work is defined as the force required to move a certain body distance, it is calculated as the product of force by distance.
therefore, the work required to raise the box is 150J.
However, the work required to keep the box lifted without moving is zero since although the box has a force due to the weight it does not move.
Answer:
The correct answer is:
doesn't change (d)
Explanation:
The total energy in a system is the sum of Kinetic and Potential energies in a system, assuming that energy is not lost to an external procedure. Now, let us define what potential and kinetic energies are:
Potential Energy: this is energy at rest or stored energy
Kinetic Energy: this is energy in motion
In a simple harmonic motion of a mass-spring system, there is no dissipative force, hence the total energy is equal to the potential and kinetic energies. The total energy is not changed rather, it varies between potential and kinetic energies depending on the point at which the mass is. The kinetic energy is greatest at the point of lowest amplitude (highest velocity) and lowest at the point of greatest amplitude (lowest velocity), while potential energy is greatest at the point of highest amplitude (lowest velocity) and lowest at the point of smallest amplitude ( highest velocity). However, at every point, the sum of kinetic and potential energies equals total energy.
Let's see
Now we know the formula of acceleration
Or
W = F x d
Lifting a couch requires a force to displace the couch a certain distance
Throwing a baseball requires a force to be applied to the base ball for it to travel a certain distance
Running up stares requires work against gravity for you to reach the top of the stairs (displacement)
Carrying a box requires no force on the box, so therefore no work is done.
