statics

• What is the definition of the Centre of Mass?

  The single point through which all mass acts
• What is a Couple in physics?

  Two equal and opposite parallel forces
• What conditions must be met for an object to be in equilibrium?

  Resultant force and moment must be zero
• What is the Moment in physics?

  The product of force and perpendicular distance
• What does the Principle of Moments state?

  Sum of clockwise moments equals anticlockwise moments
• What is a Scalar quantity?

  A quantity with only magnitude
• What is a Vector quantity?

  A quantity with both magnitude and direction
• Give examples of Scalar quantities.

  Length, mass, and temperature
• Give examples of Vector quantities.

  Velocity, displacement, and acceleration
• How do you add vectors in the same direction?

  • Simply add their magnitudes together.
• How do you add vectors in opposite directions?

  • Subtract their magnitudes.
• How do you add perpendicular vectors?

  • Use the nose-to-tail method.
  • Apply the cosine rule: $F_r^2 =$$F_1^2 +$$F_2^2 - 2F_1F_2 \cos \theta$
• What is the formula for finding the components of a vector?

  Fₓ = F cos θ, Fᵧ = F sin θ
• What does it mean for forces to be in equilibrium?

  Resultant force equals zero
• What are the steps to solve problems involving forces?

  1. Draw the diagram.
  2. Resolve forces.
  3. Take moments.
  4. Use total forces for equilibrium.
• How do you calculate the moment of a force?

  Moment = force x perpendicular distance
• What is the formula for torque in a couple?

  Torque = force x distance
• What does the principle of moments imply for a balanced system?

  Sum of clockwise moments equals sum of anticlockwise moments
• How do you calculate the tension in a system with weights?

  T = (5 x 3.6 x 10³) / 12
• How do you find the force in a system with tension?

  F = (2.5 x 13 x 10³) / 8
• What are the key skills involved in vector addition?

  • Addition of vectors by scale drawing
  • Addition of 2 vectors at right angles by calculation
  • Resolution of vectors into two components
  • Use of closed triangles for equilibrium
  • Application of principle of moments in calculations
  • Use of centre of mass for stability