The work-energy theorem states that the net work done by the forces on an object
equals the change in its kinetic energy
.
Is work done just energy?
Work done has the same units as energy
– joules. This is because energy is the ability to do work. So you must have energy to do work. … Work done is equal to energy transferred.
What is work done formula?
Mathematically, the concept of work done W equals the force f times the distance (d), that is W = f. d and if the force is exerted at an angle θ to the displacement, then work done is calculated as
W = f . d cos θ
.
What is the formula for energy?
| What is Work, Energy and Power? | Work | Energy | Definition In physics, energy is defined as the capacity to do work. | Formula For the potential energy the formula is P.E. = mgh |
|---|
Is work equal to energy?
The change in the kinetic energy of an object is equal to the net work done on the object
. This fact is referred to as the Work-Energy Principle and is often a very useful tool in mechanics problem solving. … It is in fact a specific application of conservation of energy.
Can work done be 0?
Zero work is done
when the displacement of a body is zero or perpendicular
(θ=900,cosθ=0) to the direction of force applied, then work done is zero. … Thus, the force applied and the displacement are in perpendicular directions. So, the work done is zero.
Can work done be negative?
Negative work done – The work done is said to be
negative when force and displacement are in opposite directions
. Hence, work is negative. Note: Work done by friction is always zero because friction force and displacement act in opposite directions.
In which situation is work done?
Work is said to be done
when displacement takes place in the direction of force
. When the force makes an angle with the direction of force the component of force along the direction of displacement is taken. If the force is perpendicular to the direction of displacement, work done is zero.
What is current formula?
The current is the ratio of the potential difference and the resistance. It is represented as (I). The current formula is given as
I = V/R
. The SI unit of current is Ampere (Amp).
How is work done?
Work is done
whenever a force moves something over a distance
. You can calculate the energy transferred, or work done, by multiplying the force by the distance moved in the direction of the force.
What is work done unit?
One joule
is defined as the amount of work done when a force of one newton is exerted through a distance of one meter. 1 joule of work = 1 N of force x 1 m of distance. In the English system of units, where force is measured in pounds, work is measured in a unit called the foot-pound (usually abbreviated ft-lb).
What is E mc2 used for?
Mass can be converted into pure energy
.
This is the second meaning of the equation, where E = mc
2
tells us exactly how much energy you get from converting mass. For every 1 kilogram of mass you turn into energy, you get 9 × 10
16
joules of energy out, which is the equivalent of 21 Megatons of TNT.
When we can say no work is done?
No work, as understood in this context, is done
unless the object is displaced in some way
and there is a component of the force along the path over which the object is moved. Holding a heavy object stationary does not transfer energy to it, because there is no displacement.
What does it mean when work is 0?
The work is calculated by multiplying the force by the amount of movement of an object. … Answer: Zero. Because
the object did not move
, which means its displacement was zero.
In which case is no work done?
If a force is applied but the object doesn’t move
, no work is done; if a force is applied and the object moves a distance d in a direction other than the direction of the force, less work is done than if the object moves a distance d in the direction of the applied force.
Why is a negative force attractive?
According to Coulomb, the electric force for charges at rest has the following properties: Like
charges repel each other
; unlike charges attract. Thus, two negative charges repel one another, while a positive charge attracts a negative charge. The attraction or repulsion acts along the line between the two charges.
