Physics 17 Tension and Weight (1 of 11) What is Tension?

Michel van Biezen2 minutes read

Tension is a force associated with strings, cables, or ropes, measured in Newtons, while weight is the force of gravity on an object equal to mass times acceleration due to gravity, with tension balancing weight to keep an object stationary. Newton's third law explains how the normal force counters the weight force, resulting in no net force, while the direction of tension varies based on perspective, but the magnitude remains constant throughout the string.

Insights

  • Tension is the force within strings or cables, measured in Newtons, while weight is the gravitational force on an object. Newton's third law states that the normal force counters weight, resulting in equilibrium.
  • In scenarios with pulleys and friction, tension must balance out friction to prevent movement. The direction of tension varies depending on perspective but maintains a consistent magnitude throughout the system.

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Recent questions

  • What is tension in physics?

    Tension is the force in strings or cables.

  • How is weight defined in physics?

    Weight is the force of gravity on an object.

  • What does Newton's third law state?

    Newton's third law involves normal force and weight.

  • How is tension represented in a free body diagram?

    Tension in a free body diagram equals weight.

  • What role does tension play in scenarios with pulleys and masses?

    Tension must equal friction force to prevent movement.

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Summary

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Forces of tension and weight in physics.

  • Tension is a force associated with strings, cables, or ropes, measured in Newtons, and is usually within the string or cable.
  • Weight is the force of gravity pulling down on an object, equal to the product of mass and acceleration due to gravity, which varies on different celestial bodies.
  • Newton's third law states that the normal force pushes back on an object from the earth, canceling out the weight force, resulting in no net force and no movement.
  • A free body diagram of an object suspended by a cable shows the weight pulling down and tension pulling up, with tension equal to the weight to keep the object stationary.
  • In a scenario with a pulley and masses, if friction is present, the tension in the string must equal the friction force to prevent movement.
  • The direction of tension depends on perspective; relative to an object, tension may be upward, while relative to a hook or pulley, it may appear downward, but the magnitude remains the same throughout the string.
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