3.4 Moments

• The formula for calculating moments is M = F × d
• What formula is used to calculate the moment of a force once its magnitude and perpendicular distance are known?

  $M =$$F \times d$
• The formula for calculating moments is M = F × d.


  True
• The formula for calculating moments is M = F × d
• What does the principle of moments state when an object is in equilibrium?

  The sum of the moments about any point is zero
• The unit for moments is Newton-meters (Nm).

  True
• A moment is the turning effect of a force about a point.
• What does the symbol F represent in the moment formula?

  Force
• When applying the principle of moments, the sum of the moments about a point must equal zero for equilibrium.
• What should the sum of the moments be equal to when applying the principle of moments?

  Zero
• What formula is used to calculate the moment of a force about a point?

  $M =$$F \times d$
• Write the equation representing the principle of moments when two forces F1 and F2 are acting at perpendicular distances d1 and d2 from a point of rotation.

  $F_{1} \times d_{1} +$$F_{2} \times d_{2} =$$0$
• The first step in applying the principle of moments is to identify the forces acting on the object.

  True
• Zero net force is one of the conditions for equilibrium.


  True
• What is the definition of a moment in physics?

  Turning effect of a force
• What is the formula for calculating moments?

  M = F \times d</latex>
• If a force of 50 N is applied at a distance of 0.5 m, the resulting moment is 25 Nm.


  True
• What does the principle of moments state for an object in equilibrium?

  Clockwise moments equal anticlockwise
• The principle of moments applies only to objects that are in motion.

  False
• For an object in equilibrium, the net moment about any point is zero.

  True
• When solving for unknown forces, the sum of clockwise moments must equal the sum of anticlockwise moments
• A 500 N force acting at a perpendicular distance of 1 meter produces a moment of 500 Nm.
• What is the moment produced by a 300 N force acting at a perpendicular distance of 2 meters in a clockwise direction?

  600 Nm
• Match the term with its definition:

  Center of gravity ↔️ Point where weight acts

  Weighted average method ↔️ Calculating center of gravity
• The center of gravity of a 2-part object with weights 3 kg and 5 kg positioned at 1 m and 3 m respectively is 2.25 m.


  True
• Seesaws are balanced when the moments on each side of the fulcrum are equal.
• What does zero net moment mean in the context of equilibrium?

  No net turning effect
• The unit of moment is Nm
• The variable 'd' in the moment formula represents the perpendicular distance
• What is the first step in identifying forces and their perpendicular distances?

  Identify the forces
• The formula to calculate the moment of a force is M = F \times d
• What clockwise moment is needed to balance an object if a 500 N force 1 meter to the left is balanced by a 300 N force 2 meters to the right?

  100 Nm
• Steps to solve equilibrium problems

  1️⃣ Identify forces and their directions

  2️⃣ Resolve forces into components if needed

  3️⃣ Sum forces in each direction

  4️⃣ Calculate moments about a chosen point

  5️⃣ Sum moments and set to zero

  6️⃣ Solve the resulting equations
• What is the moment produced by a 300 N force acting at a perpendicular distance of 2 meters?

  600 Nm
• The sum of clockwise moments must equal the sum of anticlockwise moments for equilibrium.

  True
• A 500 N force acting at a perpendicular distance of 1 meter in an anticlockwise direction produces a moment of 500 Nm.
• What is the formula for calculating the center of gravity position?

  \bar{x} = \frac{\sum w_{i} x_{i}}{\sum w_{i}}</latex>
• Steps to balance levers and seesaws using the principle of moments:

  1️⃣ Identify the forces and their distances from the fulcrum

  2️⃣ Use the formula F₁d₁ = F₂d₂ for levers

  3️⃣ Use the formula w₁d₁ = w₂d₂ for seesaws

  4️⃣ Solve for any unknown forces or distances
• What is the formula for balancing a seesaw using the principle of moments?

  w_{1}d_{1} = w_{2}d_{2}</latex>
• What is the definition of a moment?

  The turning effect of a force about a point