Work, Energy, And Power Flashcards
What is the formula for work done?
Work done = Force × Distance × cos(θ)
True or False: Work is a scalar quantity.
True
What unit is work measured in?
Joules (J)
Fill in the blank: The work-energy principle states that the work done on an object is equal to the change in its ______.
kinetic energy
What is the formula for kinetic energy?
Kinetic energy = 0.5 × mass × velocity²
What is potential energy?
Potential energy is the energy stored in an object due to its position or configuration.
True or False: Gravitational potential energy increases with height.
True
What is the formula for gravitational potential energy?
Gravitational potential energy = mass × gravitational field strength × height
What does power measure?
Power measures the rate at which work is done or energy is transferred.
What is the formula for power?
Power = Work done / Time taken
What unit is power measured in?
Watts (W)
Fill in the blank: 1 Watt is equivalent to ______ Joules per second.
1
True or False: The SI unit of energy is the Joule.
True
What is the principle of conservation of energy?
The total energy in a closed system remains constant; energy can neither be created nor destroyed.
What is mechanical energy?
Mechanical energy is the sum of potential energy and kinetic energy in a system.
Fill in the blank: Work done against friction is transformed into ______.
thermal energy
What is the relationship between work and energy?
Work is a transfer of energy; doing work on an object increases its energy.
True or False: Work can be done when an object is not moving.
False
What is the significance of the angle θ in the work done formula?
The angle θ represents the angle between the force applied and the direction of motion.
What is elastic potential energy?
Elastic potential energy is the energy stored in elastic materials as the result of their stretching or compressing.
Fill in the blank: The work done by a constant force is maximum when θ = ______.
0 degrees
What is the difference between renewable and non-renewable energy sources?
Renewable energy sources can be replenished naturally, while non-renewable sources are finite and will eventually deplete.
What is the formula for calculating the efficiency of a machine?
Efficiency = (Useful energy output / Total energy input) × 100%
True or False: The efficiency of a machine can exceed 100%.
False
What is the work done if a force of 10 N moves an object 5 m in the direction of the force?
50 Joules
What is the definition of a joule?
A joule is the amount of work done when a force of one newton moves an object one meter.
