A porter lifts a luggage weighing 10 kg from the ground and puts it on his head 1 m above the ground. Then the work done by him on the luggage (g is acceleration due to gravity in SI unit) is ________

The correct answer is 10g J.

Key Points

• The work done (W) by the porter on the luggage is calculated using the formula W = mgh, where m is the mass, g is the acceleration due to gravity, and h is the height.
• Here, m = 10 kg, g = 9.8 m/s² (standard value of acceleration due to gravity), and h = 1 m.
• Substituting the values, W = 10 kg × 9.8 m/s² × 1 m.
• Thus, the work done by the porter is 10g joules (since g is the symbol for 9.8 m/s²).

Additional Information

• Work Done:
  • In physics, work is defined as a measure of energy transfer that occurs when an object is moved over a distance by an external force.
  • The formula for work done is W = F × d × cos(θ), where F is the force applied, d is the displacement, and θ is the angle between the force and displacement vectors.
• SI Unit of Work:
  • The SI unit of work is the joule (J).
  • 1 joule is equivalent to 1 newton-meter (N·m).
• Gravitational Force:
  • Gravitational force is the force of attraction between two masses.
  • It is given by the formula F = mg, where m is the mass and g is the acceleration due to gravity.
• Energy Transfer:
  • Work is a form of energy transfer from one system to another.
  • When work is done on an object, energy is transferred to the object, often resulting in a change in its kinetic or potential energy.