5-Forces (2) Flashcards
What is a force?
A push or pull that acts on an object due to the interaction with another object. It’s a vector quantity
What is a contact force?
A force where the objects are physically touching
What is a non-contact force?
A force where the objects are physically seperated
What are some examples of contact forces?
*Friction
*Air resistance
*Tension
*Normal contact force
What are some examples of non-contact forces?
*Gravitational force
*Electrostatic force
*Magnetic force
What is a vector?
A vector quantity has both magnitude and direction
What are examples of vector quantities?
*Force
*Velocity
*Displacement
*Acceleration
*Momentum
What is a scalar quantity?
A scalar quantity only has magnitude, no direction.
What are examples of scalar quantities?
*Speed
*Distance
*Mass
*Temperature
*Time
What does the length and direction of an arrow show when representing Vectors?
*Length shows magnitude
*Direction shows direction of the vector quantity
What does gravity do?
*On surface of planet, makes everything fall to the ground
*gives everything a weight
What is the definition of weight?
The force acting on object due to gravity
What is gravitational field?
The force of gravity close to the earth
What does the weight of an object depend on?
The gravitational field strength at the point where the object is
How can weight of an object be calculated?
Weight=mass X gravitational field strength (weight in N, mass in kg, grav field strength in N/kg)
What is centre of mass?
Point on an object that weight is considered to be acting
How is weight measured?
A newtonmeter (calibated spring-balance)
What is the resultant force?
A single force that has the same effect of all original forces replacing a number of forces acting on an object.
What is work done?
A force causing an object to move through a distance
What are the units for the work done equation?
Work done in Joules, Force in Newtons, distance in meters
What is one joule equivalent to?
1 Joule=1 newton metre
*one joule work done when one newton causes displacement of one metre
What happens when work is done against the frictional forces acting on an object?
It causes a rise in temperature on the object.
