Forces Flashcards
What is force measured in?
Force is measured in a unit called newtons, N.
What do free-body force diagrams show?
Free-body force diagrams show all the forces acting on an object
What happens if there is no resultant force acting on an object?
- if stationary, the object will remain the same
- if moving, the object will keep moving at a constant speed in a straight line
What happens if you double the size of the resultant force?
If you double the size of the resultant force, it will double the acceleration.
What happens is you double the mass?
If you double the mass, it will halve the acceleration.
What is Isaac Newton’s first law?
If there is no resultant force acting on an object, then if stationary, the object will remain at rest and if moving, the object will keep moving at a constant speed in a straight line.
What is Isaac Newton’s third law?
When two objects interact, each object exerts an equal but opposite force on the other. We call these equal and opposite action and reaction forces.
What is the equation to work out the resultant force?
resultant force (newton, n) = mass (kg) x acceleration (m/s2)
What is the equation to work out weight?
weight (newton, n) = mass (kilogram, kg) x gravitational field strength (newton per kilogram n/kg)
What 2 things do all falling objects have in common?
- the same acceleration of free-fall (10 m/s)
- an acceleration that is independent on their mass
What happens to air resistance as speed increases?
Air resistance increases as speed increases.
What is terminal velocity?
Air resistance increases as speed increases, until the air resistance is equal to the weight of the object. At this point, the resultant force on the object is zero. The object has reaches a constant velocity known as terminal velocity.
