lab 4 Forces Flashcards
A force is a ____ quantity
A force is a vector quantity capable of producing motion or a change in motion. In the SI unit system, the unit of force is the Newton (N). The properties and effect of forces in the physical world are described by Newton’s three laws of motion.
First law of Motion (Law of Inertia)
An object moving uniformly in a straight line will continue to move with constant velocity unless a net force act on it. An object at rest remains at rest as long as no net force acts on it.
Second law of Motion (Law of Mass and Acceleration)
The acceleration of an object is proportional to the net force acting on it and is inversely proportional to the mass of the object.
Acceleration =
Net Force/Mass
Third law of Motion (Law of Action and Reaction)
For every force that acts on an object, there is a reaction force that is equal in magnitude and opposite in direction.
Although there are many types of forces in the Universe, they are all based on four fundamental forces.
The strong and weak forces only act at very short distances and are responsible for holding nuclei together. The electromagnetic force acts between electric charges and the gravitational force acts between masses. Some other examples of forces are: resistive force acting between two objects in contact with one another is called the frictional force; and the force acting on strings called the tension.
- Balanced /Unbalanced Forces
Forces that are equal in size but opposite in direction are called balanced forces.
Balanced forces do not cause a change in motion. Forces that cause a change in the motion of an object are unbalanced forces.
mass
if the mass increases, so does the
force
The force increases as the mass increases because there is more of a force of attraction
distance
When distance is changed,
force is affected.
Force
There is more of a force of attraction when the two objects are closer together
What is the standard unit of force in the metric system?
Newton
Which of the following forces is the resultant gravitational force on an object?
Weight
Which of the following is NOT a valid observation from the tug-of-war simulation in Lab 04?
The mass of the cart changes with the net force.
A book is lying at rest on a table. Which is a correct observation?
There is no net force on the book.`
You push a 100 kg couch with a force of 1000 newtons over a carpet that provides a frictional resistance force of 400 newtons. What is the resulting acceleration of the couch?
acceleration= force/mass 6 m/s2
Which statement is NOT supported by Newton’s Laws of Motion?
The direction of the acceleration of an object is the same as the direction of the biggest force acting on it.
