Work and Energy | Grade 8 Science DepEd MELC-Based Quarter 1 Module 3 Part 1 Work

Summary

This educational video explores the concept of 'work' in various contexts, from employment to physics. It explains that in physics, work is related to energy transfer, occurring when a force causes displacement in the direction of the force. The formula for calculating work (W = force × displacement) is introduced, with the unit of work being the joule, named after James Prescott Joule. The video also illustrates work with everyday examples like pushing a chair and rolling a ball, emphasizing the energy transfer involved in these actions.

Takeaways

• 🔧 The term 'work' has various meanings, including a job or employment, tasks or activities to be accomplished, and an abstract concept in physics related to energy.
• 🏢 When asked where you work, it typically refers to your job or place of employment.
• 📚 In an educational context, 'work' refers to tasks or activities like homework that need to be completed.
• 🔨 In physics, work is associated with energy and involves a change in energy when it is done.
• 🚶‍♂️ Work is done by an object when it loses energy, and work is done on an object when it gains energy.
• 📐 For work to be done on an object, a force must be applied and the object must move in the direction of the force.
• 📏 The formula to calculate work is Work = Force × Displacement, where the unit of work is the joule (newton meter).
• 👨‍🔬 The unit 'joule' is named after the English physicist James Prescott Joule and is also a unit of energy.
• 🛠️ An example calculation of work involves pushing a chair with a force of 500 newtons over a displacement of 7 meters, resulting in 3500 joules of work done.
• 🎳 In the provided bowling game example, work is done on the ball when it is pushed, transferring energy to it, which then moves as kinetic energy.
• 🧠 The script encourages viewers to keep their minds busy and to subscribe for more educational content.

Q & A

What is the general meaning of the word 'work' in everyday language?

In everyday language, 'work' often refers to a job or employment, or to tasks or activities that need to be accomplished, such as homework.

How is 'work' defined in physics?

In physics, 'work' is defined as the process in which energy is transferred to or from an object when a force is applied, causing displacement in the direction of the force.

What must happen for work to be considered as done on an object?

For work to be considered as done on an object, a force must be applied to the object, and the object must move in the direction of the applied force.

What is the formula used to calculate work done by a force?

The formula to calculate work is: Work = Force × Displacement.

What are the units of force and displacement in the work formula?

The unit of force is the newton (N), and the unit of displacement is the meter (m).

What is the unit of work, and who is it named after?

The unit of work is the joule (J), named after the English physicist James Prescott Joule.

How much work is done if a 500 newton force pushes a chair 7 meters?

The work done is 3,500 joules, calculated by multiplying the force (500 newtons) by the displacement (7 meters).

In the example of rolling a ball to hit bottles, is work done on the ball, and why?

Yes, work is done on the ball because the force exerted on it causes the ball to move in the same direction as the force applied.

What is the relationship between force, work, and energy as described in the script?

The force applied to an object does work on the object, and this work results in a transfer of energy to the object, often causing it to move.

What key concept is emphasized about the direction of force and displacement in the context of work?

The key concept emphasized is that for work to be done, the force applied must cause displacement in the same direction as the force.