Forces Flashcards
Name three types of forces
Contact, non-contact, reactant
Name three contact forces
friction, drag (air and water resistance), thrust, upthrust, tension and reaction
Name three non-contact forces
Gravitational, electrostatic and magnetic forces
How do you measure a force
With a forcemeter also called a newtonmeter
What unit is used to measure a force
Newton
Fill in the blanks: An arrow shows the ……….. of the force (the longer the arrow, the …… the force) and the …….. in which the force acts.
size, bigger, direction
Fill in the blank:
When two forces acting on an object are equal in size but act in opposite directions, we say that they are …… forces
balanced
The resultant force on a moving object is 0 Newton. What happens to the object?
It keeps moving at a steady speed in the same direction
The resultant force on a stationary object is 0 Newton. What happens to the object?
It stays still
Why does a boat float
A boat floats because its weight is balanced by the upthrust from the water
Fill in the blank:
The weight of a book lying on a table is balanced by the ……. force from the table top
Reaction
Fill in the blank:
If the forces on an object are unbalanced this is what happens:
- an object that is not moving ……….
- an object that is moving changes ………
starts to move
changes speed or direction
Fill in the blank:
When two forces acting on an object are unequal in size or do not act in opposite directions, we say that they are …… forces
Unbalanced
What is a resultant force
The size of the overall force acting on an object is called the resultant force.
What is the resultant force when the forces are balanced?
0 Newton
