Newton’s First Law (Law of Inertia):
An object will stay at rest or keep moving in a straight line at the same speed unless a force acts on it.
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What It Means:
Things don’t start moving, stop, or change direction unless something makes them.
• If something is not moving, it won’t move unless you push or pull it.
• If something is already moving, it won’t stop or turn unless a force slows it down or changes its path.
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Real-Life Example:
A soccer ball on the ground stays still until you kick it.
Once it’s rolling, it would keep going forever — unless the ground, air, or something else slows it down.
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In simple words:
“Things stay how they are unless a force changes them.”
Newton’s Second Law:
Force = Mass × Acceleration
(Or written as: F = m × a)
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What it Means:
This law tells us that the more mass an object has, or the faster you want it to move (accelerate), the more force you need.
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Simple Example:
Imagine trying to push two objects:
• One is an empty box.
• The other is a box full of books.
If you push both with the same force, the empty box will move faster because it has less mass.
To move the heavy box at the same speed, you would need to push harder.
So, the heavier the object or the faster you want it to move, the more force you need.
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In simple words:
“Heavier things are harder to move. To move faster, you need more force.”
Newton’s Third Law — Simple Meaning:
For every action, there is an equal and opposite reaction.
This means:
• When one object pushes or pulls another, the second object pushes or pulls back with the same amount of force, but in the opposite direction.
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Real-Life Example:
When you jump off a small boat, you move forward — but the boat moves backward.
That’s because:
• Your legs push on the boat (action),
• The boat pushes back on you with the same force (reaction), but in the opposite direction.
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In simple words:
“Push something, it pushes back just as hard.”
Why does a coin placed on a card over a glass fall into the glass when the card is quickly flicked away?
Can an object be in motion if no force is acting on it? How does this relate to everyday experiences?
Why is it easier to push an empty shopping cart than a full one?
How does increasing the mass of an object affect the force needed to accelerate it?
If two objects with different masses are subjected to the same force, how will their accelerations differ?
In a tug-of-war, if both teams pull with equal force but one team moves forward, what explains this?
If a fish swims by pushing water backward, how does Newton’s third law explain its forward motion?