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### Course: Middle school physics>Unit 3

Lesson 1: Kinetic energy

# Kinetic energy

Review your understanding of kinetic energy in this free article aligned to NGSS standards.

## Key points:

• Kinetic energy is the energy that any object with mass has simply because it is moving. If an object is not moving, it has no kinetic energy.
• An object’s kinetic energy is directly related to its mass. Imagine two objects moving at the same speed. If one object has twice the mass of the other, it will also have twice the kinetic energy.
• An object’s kinetic energy is also related to the squared value of its speed. Imagine two objects with the same mass. If one is moving at twice the speed of the other, the faster object will have four times the kinetic energy.

## Want to join the conversation?

• How would you get the mass of the object ?
How would you get the weight of the object ?
• Mass and weight are actually not the same thing in Physics, even though we sometimes use the words interchangeably in everyday life. Mass can be described as “how hard it is to move” something. Imagine you and an elephant are each on a skateboard. If we gave the same push to each of you, you would move a lot more than the elephant. That’s because you are less massive than an elephant.

Weight is the force of gravity acting on an object. Because gravity can be stronger or weaker depending on what planet (or other object) you’re near, your weight changes too! If you went to the Moon, the force of gravity on you would be about one-sixth what it is on Earth. That means that even though your mass is the same on the Earth or Moon, you’d weigh much less on the Moon!

We often measure an object’s mass by comparing how gravity (in the same location) acts on a known mass for comparison. If you see a balance-style scale, it’s measuring mass.

Weight is measured like other forces. Many bathroom scales use springs to measure the force of gravity acting on the object on top of them. This means if you took a bathroom scale to the Moon, it would read one-sixth your weight on Earth.

Does that help?
• how can we find the mass
• It will usually be given in most exercises
• How can we get the mass of an object
• If the object is small enough to fit on a scale then we just weigh it.
• How can we get the mass of an object
• Mass = Density * Volume
• Is a A ball has a mass of 2Kg, suppose it travels at 10m/s. Find the kinetic energy possessed by it kenetic energy?
• Does M stand for Mass?
• Yes,"M" stand for mass.
• my brain hurts 🤕
• Don't worry. We all are scared about physics at first but eventually we can do it easily