UNIT 4.1: MECHANICAL WORK & POWER

Does moving a rock mean you are doing Work?

In Science, "Work" isn't just sitting at a desk. Let's discover what it truly means to do work and how fast you can do it.

The Aigerim Dilemma

Aigerim pushes a giant stone at the Charyn Canyon. She pushes very hard, sweating and tired, but the stone does not move.

Canyon

Explore

Interactive Simulations

Change the variables and see how Force, Distance, and Time affect Work and Power.

The Work Calculator

Help Alisher push a heavy box of books in the library.

50 N
2 m

Total Work Performed

100 Joules

W = F × d

The Power Race

Sultan and Dameli are climbing the Medeu stairs. They do the same work (60,000 J).

10 min
100 W
20 min
50 W

Sultan is faster, so he has more Power!

Explain

The Rules of Physics

Work (W)

Work characterizes the process of energy transfer. It happens when a force acts upon an object, causing it to move.

W = F × d
  • W = Work in Joules (J)
  • F = Force in Newtons (N)
  • d = Distance in meters (m)

Power (P)

Power is the "speed" of work. It is a physical quantity that represents the rate at which work is performed per unit of time.

P = W / t
  • P = Power in Watts (W)
  • W = Work in Joules (J)
  • t = Time in seconds (s)

Bilingual Vocabulary

English Russian Kazakh
Weight Вес Салмақ
Speed Скорость Жылдамдық
Environment Окружающая среда Қоршаған орта
Steam Engine Паровой двигатель Бу қозғалтқышы

Fun Facts!

Zero Work!

When you carry a heavy backpack on a flat floor, you do 0 Work in physics because the force is "up" but movement is "forward".

Horsepower

James Watt invented HP to compare engines to horses. 1 HP = 735 W. A pro cyclist can produce ~400W!

Elaborate

Science & Society (Criterion D)

Why do we care? How do Work and Power impact our daily lives?

Electric Scooter
1

Making Life Easier

Nurlybek uses an electric scooter to go to school. Powerful machines save us Time, doing work faster so we don't have to!

Microwave Label
2

Reading Labels

A 1000W microwave cooks food faster than a 700W one because it uses 1000 Joules of energy every second. Choosing lower Watt appliances saves money!

Windmills
3

The Environment

High power = high energy use. In Kazakhstan, we are shifting to "Green Energy" (wind/sun) to get the Power we need without hurting the Environment.

Evaluate

Check Your Understanding

Physics Challenge

Score: 0/3

Level 1 (Easy): Find Work (W) if Force = 10 N and Distance = 5 m.

Level 2 (Medium): Find Power (P) if Work = 300 J and Time = 10 s.

Level 3 (Hard): A boy pushes a box with F = 20 N for d = 5 m in t = 2 s. What is his Power?

Hint: First find Work (W = F×d), then find Power (P = W/t).

Pair Discussion Task

Student A: Explain to your partner why Aigerim did "zero work" on the stone at Charyn Canyon.

Student B: Look at two vacuum cleaners (Cleaner A: 1000W, Cleaner B: 2000W). Explain to your partner which one works faster and why high power might be bad for the environment.

Both: Talk about Alisher's box. If the box was two times heavier, would the Work be more or less? Discuss.