powerIn physics, power is the rate of doing work. It is the amount of energy consumed per unit time. The unit of power is the joule per second (J/s), known as the watt (in honor of James Watt, the eighteenth-century developer of the steam engine).
What is rate of doing work class 9?
The time rate of doing work is defined as power (P). Power= work/time. Unit of power. sI unit of Power is Joule per second or Js1. 1 watt is the power when 1J of work is done in 1s.
How do we measure the rate of doing work?
Power is often measured in joules of work per second. The unit of measurement for power is the (W). One watt is equal to one joule of work done in one second. If an object does a large amount of work, its power is usually measured in units of 1000 watts, or kilowatts.
What does rate of work done mean?
The rate of doing work is equal to the rate of using energy since the force transfers one unit of energy when it does one unit of work. A horsepower is equal to 550 ft lb/s, and a kilowatt is 1000 watts.
What is work class 11?
When a force acts on an object and the object actually moves in the direction of force, then the work is said to be done by the force. Work done by the force is equal to the product of the force and the displacement of the object in the direction of force.
What is energy class 8?
The capacity of doing work is called energy. Rate of doing work is called power. It can also be defined as the rate of change of energy. … An object can have value for the power without doing any work.
What is the rate at which work is done or performed?
The rate at which work is done is called Power. Power, word done and time are related to each other as Power = Work/Time. Force is related with work as Force = Work*Displacement. Energy and work are expressed together through relation Energy = Power*Time.
Is work and work done same?
To express this concept mathematically, the work W is equal to the force f times the distance d, or W = fd. If the force is being exerted at an angle θ to the displacement, the work done is W = fd cos θ. … No work is done in either case.
Is work equal to energy?
No. The principles of physics say that while work is performed by different forms energy, work done cannot be equal to the energy used or applied for.
What is short answer job?
In physics, work is defined as a force causing the movement—or displacement—of an object. … This definition is consistent with the proper definition because a constant force integrates to merely the product of the force and distance. Work is force applied over distance.
What is work class 9 short answer?
Work is said to be done when a force causes displacement of an object in the direction of applied force. Q2. Write an expression for the work done when a force is acting on an object in the direction of its displacement. Q3.
What is the heat?
Heat is the form of energy that is transferred between systems or objects with different temperatures (flowing from the high-temperature system to the low-temperature system). Also referred to as heat energy or thermal energy. Heat is typically measured in Btu, calories or joules.
What is the 1 watt of power?
1 watt is the power of an agent, which does work at the rate of 1 joule per second. Power is 1 watt when the rate of consumption of energy is 1 joule per second.
What is light energy?
Light energy is a form of energy and is expressed in joules. … It is the visible light that is detected by the human eye. It is also the visible light that drives photosynthesis. Blue and red wavelengths are the chlorophylls’ two most effectively absorbed wavelengths of the visible light.
How fast is work done?
Power is the work done in a unit of time. In other words, power is a measure of how quickly work can be done. The unit of power is the Watt = 1 Joule/ 1 second.
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.
Is work net force?
Net Work and the Work-Energy Theorem. … Net work is defined to be the sum of work done by all external forces—that is, net work is the work done by the net external force Fnet. In equation form, this is Wnet = Fnetd cos θ where θ is the angle between the force vector and the displacement vector.
Is work a vector?
Work is not a vector quantity, but a scalar quantity.
Does work have direction?
Work is a scalar quantity, so it has only magnitude and no direction.
What is Net work?
Net work done on an object equals the object’s change in kinetic energy. Also called the work-energy principle.
Is the ability to do work?
The ability to do work is called energy. Work is actually a transfer of energy. When work is done to an object, energy is transferred to that object. … There are 2 types of Mechanical Energy: kinetic energy and potential energy Kinetic Energy (KE) is the energy of motion.