What is equilibrium? Describe the conditions of equilibrium. State and explain the principle of moments.

Equilibrium refers to a state in which an object remains at rest or in uniform motion, without any net force or torque acting on it.

Conditions of equilibrium:

  1. Translational equilibrium: The vector sum of all forces acting on the body must be zero. This means that the forces in all directions (both horizontally and vertically) must cancel out.
  2. Rotational equilibrium: The sum of all torques (moments of force) acting on the body must be zero. This means that there is no net torque causing rotation about any axis.

Principle of Moments: The principle of moments states that for an object to be in rotational equilibrium, the sum of the clockwise moments must equal the sum of the counterclockwise moments about any axis. Mathematically, it can be written as:

∑τclockwise=∑τcounterclockwise

Where τ represents the torque (moment of force).

This principle is used in balancing objects, like a seesaw or a balance scale.

Related Questions:

  1. Define center of mass. What is the effect of mass distribution in a body on its center of mass?
  2. What is the center of gravity? Where will be the center of gravity of these regular shaped bodies: circular plate, rectangular and square-shaped plate, triangular shaped plate, cylinder, sphere? (Also draw figures to support your answer). Differentiate between center of mass and center of gravity.
  3. How can you find the center of gravity of an irregular shaped thin sheet of plastic?
  4. Q1. Write the following numbers in scientific notations.
  5. Q2. Express the followings measurements using prefixes.
  6. Q3. If a boy has age of 15 years 2 months and 10 days, convert his age in a. seconds b. milliseconds c. mega seconds
  7. Q4. How many kilometers are there in 25 micrometers?
  8. Q5. What is pitch and least count of: a. Vernier calipers if the smallest division on the main scale is 1 mm and total divisions on the vernier scale are 20. b. Screw gauge if the smallest division on its main scale is 0.5 mm and its movable scale has 50 divisions.
  9. Q6. Look at the measurement of vernier calipers:
  10. Q7. Look at the figure of screw gauge, let a small steel ball is place between its thimble and anvil then:
  11. Why door knobs are fixed at the edge of door? What will happen it the door knob is at the middle of the door?
  12. If you drop a feather and a bowling ball from the sane height, which one will reach the terminal velocity first? Which one of them will hit the ground first?
  13. Why do ice skates effortlessly slide on ice, while your shoes cause skidding?
  14. Explain why it’s easier to push a car on flat tyres than inflated ones. What happens to the frictional force between the tyres and the road?
  15. Why a moving bicycle is easier to balance? Relate this to the principles of rotational motion.
  16. Why is a pencil standing on its tip unstable, and what factors affect the stability of an object balanced on a point?
  17. While driving what happens if the driver take the curve too fast? How does centripetal force play a role in keeping the car from skidding off the road?
  18. Consider a situation where you swing a ball connected to a string in a circle. How does the tension in the string vary as the ball moves across different points in its circular path, and what forces are involved?
  19. Why is it important for communication satellites in geostationary orbit to maintain a specific speed?
  20. Differentiate between like and unlike parallel forces.