Equilibrium | Physics for GCSE/IGCSE - Year 11 PDF Download

Equilibrium

• Equilibrium refers to a state where an object maintains its current state without any alteration.
  • If the object is in motion, it will persist in moving, following a straight path.
  • If the object is stationary, it will remain still.
  • Furthermore, there will be no initiation or cessation of rotation.
• These conditions necessitate two factors:
  • The forces acting upon the object must be in equilibrium, or balanced.
  • There must be an absence of resultant force.
• Additionally, the total clockwise moments acting on the object must equal the total counterclockwise moments.
  • This requirement ensures that there is no resultant moment present.

• Meeting the aforementioned two conditions ensures that the object achieves equilibrium.

Demonstrating Equilibrium

• When showcasing equilibrium in a simple experiment, we can replace the supports of an object like a beam with newton (force) meters.

• The depicted beam is in a state of equilibrium.
• Determining the various forces acting on the beam can be accomplished by either recording readings from the Newton meters or by measuring the masses, subsequently calculating the weights of both the beam and the suspended mass.
• The distance of each force from the end of the ruler can then be gauged, enabling the calculation of the moment produced by each force around the end of the ruler.
• Consequently, it can be demonstrated that the total clockwise moments, resulting from forces F₂ and F₃, are equal to the total counterclockwise moments, arising from forces F₁ and F₄.

More detail on setting up this experiment

• Utilize a meter ruler for the beam
• Suspend the beam using two Newton meters, one on each side, hanging from a clamp stand
• F₁ represents the reading from the Newton meter on the left side, and F₄ represents the reading from the right side
• Create a loop of string, tie a secure knot, and slide the ruler through it
• F₃ indicates the weight of a mass hook with 10 N weights suspended from this string
• F₂ represents the weight of the beam