The Kinetic energy of objects Flashcards
(19 cards)
What is the equation for work done?
work done (joule, J) = force (newton, N) × distance (metre, m)
A force of 10 N is applied to a box to move it 2 m along the floor. What is the work done on the box?
The work done is 10 × 2 = 20J
When can work done be calculated?
The work done on an object can be calculated if the force and distance moved are known.
What is the equation for power?
Power = work done ÷ time
What is power measured in? (Work done equation)
Watts, W
What is work done measure in?(Work done equation)
Joules, J
What is time measured in?(Work done equation)
Seconds, s
An electric drill transfers 3000 J in 15 s. What is its power?
Power = 3000 ÷ 15 = 200 W
What is weight of an object?
The weight of an object is the size of the force of gravity pulling the object down. When an object falls it transfers GPE to KE (kinetic energy).
What is the equation for Gravitational Potential Energy?
GPE (J) = mass (kg) x gravitational field strength (or ‘g’) (N/kg) x height (m)`
What is the equation of weight?
weight (N) = mass (kg) x gravitational field strength (N/kg)
What is the equation for Kinetic Energy?
Kinetic Energy = ½ × m × v2
What is Kinetic Energy measured in? (Kinetic Energy equation)
Joules, J
What is mass measured in? (Kinetic Energy equation)
Kilograms, Kg
What is velocity measured in? (Kinetic Energy equation)
Metres per second, m/s
What is Gravitational Potential Energy?
Any object that is raised against the force of gravity stores gravitational potential energy. For example, if you lift a book up onto a shelf, you have to do work against the force of gravity. The book has gained gravitational potential energy.
What is Elastic Potential Energy?
Elastic objects such as elastic bands and squash balls can change their shape. They can be stretched or squashed, but energy is needed to change their shape. This energy is stored in the stretched or squashed object as elastic potential energy.
What is Kinetic Energy?
Every moving object has kinetic energy (sometimes called movement energy). The more mass an object has, and the faster it is moving, the more kinetic energy it has. You should be able to discuss the transformation of kinetic energy to other forms of energy.
What is momentum?
A moving object has momentum. This is the tendency of the object to keep moving in the same direction. It is difficult to change the direction of movement of an object with a lot of momentum.
