work, energy and power Flashcards
revision (31 cards)
What is the formula for work done?
Work done = Force x Distance x cos(θ)
True or False: Work done is a scalar quantity.
True
Fill in the blank: The unit of work done is ______.
Joule
What is the relationship between work and energy?
Work done on an object results in a change in energy.
Multiple Choice: Which of the following is NOT a unit of power? A) Watt B) Joule C) Horsepower D) Newton
D) Newton
What is the formula for power?
Power = Work done / Time taken
True or False: Power is defined as the rate at which work is done.
True
Fill in the blank: The SI unit of power is ______.
Watt
What is kinetic energy?
The energy an object possesses due to its motion.
What is the formula for kinetic energy?
Kinetic Energy = 1/2 mv²
Multiple Choice: Which of the following describes gravitational potential energy? A) Energy due to motion B) Energy stored due to position C) Energy of deformation D) None of the above
B) Energy stored due to position
What is the formula for gravitational potential energy?
Gravitational Potential Energy = mgh
True or False: Energy can be created and destroyed.
False
Fill in the blank: The principle of conservation of energy states that energy cannot be ______.
created or destroyed
What is the work-energy principle?
The work done on an object is equal to the change in its kinetic energy.
Multiple Choice: If the force applied to an object is in the same direction as the displacement, what is the value of θ in the work formula? A) 0° B) 90° C) 180° D) 45°
A) 0°
What does it mean if work done is negative?
The force applied is in the opposite direction to the displacement.
Fill in the blank: The total mechanical energy of an object is the sum of its ______ and ______.
kinetic energy, potential energy
What does a watt measure?
A watt measures the rate of energy transfer equivalent to one joule per second.
True or False: If no work is done on an object, its energy remains unchanged.
True
What is the formula to calculate the work done against gravity?
Work done = mgh
Multiple Choice: Which factor does NOT affect the amount of work done? A) Force applied B) Distance moved C) Direction of motion D) Time taken
D) Time taken
What is elastic potential energy?
The energy stored in an object when it is compressed or stretched.
What is the formula for elastic potential energy?
Elastic Potential Energy = 1/2 kx²