Understanding Machine Work Output and Input
In any practical machine, energy is always lost due to unavoidable factors like friction and air resistance. Friction opposes the motion, converting some of the energy supplied into unwanted heat or sound.
Work Output vs. Work Input Principle
- Work Input: This is the total energy or work supplied to the machine.
- Work Output: This is the useful work done by the machine.
- Friction's Effect: Friction acts as a resistive force, meaning it requires energy to overcome it. This energy used to overcome friction does not contribute to the useful work output.
Conclusion on Machine Performance
Because a portion of the work input is inevitably used to overcome friction and other dissipative forces, the work output obtained from the machine will always be less than the work input.
Mathematically, if '\(W_{in}\)' is the work input and '\(W_{out}\)' is the work output, then in a real machine:
\(W_{out} < W_{in}\)
This inequality holds true due to energy losses, primarily caused by friction.
Similar Questions
- The work done by a 10 Newton force acting on a body, which results in the displacement of 2 m in the direction of the force, is __________.
- An object of mass 1 kg is moving with a velocity 10 m/s. Find the kinetic energy of the object.
- The efficiency of a machine can never be ______.
- How much energy is used by an 80% efficient, 2kW motor running at a peak load for 5 hours?
- A pump is required to lift 600 kg of water per minute from a well 25m deep and to eject it with a speed of 50 m/s. If \(g = 10 \text{ m/s}^2\), the power required to perform the above task is
- A lorry and a car moving with the same kinetic energy are brought to rest by applying the same retarding force. Then:
- In practice, the work output of a machine is always less than the work input due to the effect of ______.
- Ideal machines are those imaginary machines which are ______.
- The efficiency of a simple machine is defined as ______.
- An object of mass m follows a circular path of radius r with a constant speed v in uniform circular motion. Then, the work done by the centripetal force for the object to move once in a full circle is
Important Questions from Work Power and Energy
Which of the following is an example of potential energy?
_______ is one of the chemical used to produce Ocean Thermal Energy.
A body of mass 2kg is thrown up vertically with a kinetic energy of 500J. If the acceleration due to gravity is 10 m/s2, the height at which the kinetic energy of the body becomes half of the original values is _____
Arjun has a mass of 50 kg, he eats banana of 1000 calories. If this energy is used up to lift him from the ground, the height to which he can climb is _______. Take g = 10 m/s2 and 1 calories = 4.2 Joule.
When a body of mass 'm' attains a velocity 'v' from rest in time 't', then kinetic energy of translation is:
