Forces Flashcards
What is a force?
A force is an influence that causes an object to change. Gravity is an example of a force. Pushes and pulls are examples of forces but they are not the only ones.
Which force did Charles-Augustin de Coulomb first describe?
Charles-Augustin de Coulomb first described the electrostatic force. Isaac Newton first described gravity.
What does Newton’s First Law of Motion state?
Newton’s First Law states that objects with balanced forces acting on them will stay at rest or in constant motion. F = ma is an equation which summarises Newton’s Second Law.
What are the units of force?
The units of all forces are newtons. A bag of sugar has a gravitational force (weight) of 10 newtons.
Newton’s Second Law of Motion can be summarised by which equation?
Newton’s Second Law of Motion can be summarised as F = ma. It relates to unbalanced forces
What is friction?
Friction is a force that opposes motion. It acts when two or more surfaces slide past each other.
How do you calculate resultant force?
The resultant force is calculated by adding together all the forces that act upon an object. Dividing these forces will not give you a useful value.
What happens if the resultant force on a car is in the direction in which it is travelling?
If the resultant force on a car is in the same direction as the car is travelling it will speed up.
What is the gravitational field strength of the Moon?
The gravitational field strength of the Moon is 1.6 N/kg. 10 N/kg is the gravitational field strength of Earth.
If a person has a weight of 600 N, how much will they weigh on the Moon?
Weight is mass multiplied by gravitational field strength. A weight of 600 N is equivalent to a mass of 60 kg. So 60 kg x 1.6 N/kg is 96 newtons (N). 600 N is their weight on Earth