2.2 Forces and Free-Body Diagrams

• The normal force acts perpendicular to a surface.


  True
• What is another name for Newton's First Law?

  Law of Inertia
• What is the mathematical expression for Newton's Second Law?

  $F_{net} =$$m \times a$
• What is the relationship between acceleration, net force, and mass according to Newton's Second Law of Motion?

  F_net = m * a
• What is the unit of acceleration?

  m/s²
• Match the type of force with its description:

  Gravity ↔️ Attracts objects towards each other

  Normal Force ↔️ Acts perpendicular to a surface

  Friction ↔️ Opposes motion between surfaces

  Tension ↔️ Exerted by a taut string or cable
• What is the unit of net force in Newton's Second Law?

  Newtons
• The action and reaction forces in Newton's Third Law have equal magnitude
• What is the symbol used to represent gravity in a free-body diagram?

  $F_{g}$
• In a free-body diagram, the gravitational force is represented by the symbol F_g
• In a free-body diagram, the length of the force arrow represents the force's magnitude
• A free-body diagram helps visualize the forces acting on an object, which is crucial for solving dynamics problems.


  True
• Match the force with its direction in a free-body diagram for a box on a table:

  Gravitational force ↔️ Downward

  Normal force ↔️ Upward
• Friction opposes motion
• An object in motion remains in motion unless acted upon by an unbalanced force.

  True
• Mass measures an object's resistance to acceleration
• The net force in Newton's Second Law is measured in Newtons
• Steps to calculate the acceleration of an object using Newton's Second Law

  1️⃣ Identify the net force acting on the object

  2️⃣ Determine the mass of the object

  3️⃣ Apply the formula a = F_net / m

  4️⃣ Calculate the acceleration
• What is another name for Newton's First Law of Motion?

  Law of Inertia
• Arrange the steps to calculate acceleration using Newton's Second Law:

  1️⃣ Identify the net force acting on the object

  2️⃣ Determine the mass of the object

  3️⃣ Apply the formula F = ma

  4️⃣ Calculate the acceleration a = F / m
• In the example of a box on a table, what force is considered the action?

  Gravity
• In a free-body diagram, the normal force is represented by the symbol F_N</latex>
• When a box is at rest on a level surface, the normal force equals the gravitational force.


  True
• Steps to construct a free-body diagram

  1️⃣ Identify the object

  2️⃣ Identify the forces

  3️⃣ Draw the forces as arrows

  4️⃣ Organize the diagram
• What are examples of forces that might appear in a free-body diagram?

  Gravity, normal force, friction
• What is the first step in applying free-body diagrams to solve problems?

  Identify the object
• By using a free-body diagram, you can analyze the forces acting on an object and solve for unknowns like normal force or acceleration.


  True
• What is a force defined as?

  An interaction that changes motion
• Match the type of force with its description:

  Gravity ↔️ Attracts objects towards each other

  Normal Force ↔️ Acts perpendicular to a surface

  Friction ↔️ Opposes motion between surfaces

  Tension ↔️ Force exerted by a string

  Applied Force ↔️ External force by object or person
• An object at rest will remain at rest unless a net force
• Steps to calculate the acceleration of an object using Newton's Second Law

  1️⃣ Identify the net force acting on the object

  2️⃣ Determine the mass of the object

  3️⃣ Apply the formula $F_{net} =$$m \times a$

  4️⃣ Solve for acceleration $a$
• Mass measures an object's resistance to acceleration.


  True
• A force, when unopposed, will change the motion
• Newton's Second Law states that acceleration is inversely proportional to mass
• Newton's Third Law states that for every action, there is an equal and opposite reaction.

  True
• Steps to draw a free-body diagram:

  1️⃣ Represent the object as a point or shape

  2️⃣ Identify all forces acting on the object

  3️⃣ Draw arrows representing each force

  4️⃣ Label each force with its name and magnitude
• What is the definition of friction as a force in physics?

  Opposes motion between surfaces
• What is a free-body diagram used for in physics?

  Analyzing object motion
• Overlapping force arrows in a free-body diagram are acceptable if they are of equal magnitude.

  False
• When a box is placed on a table, the normal force acts in a direction upward