According to first law of motiona)body acted on by no net force moves ...
Newton's first law of motion states that an object at rest remains at rest and an object in motion remains in motion with the same velocity unless acted upon by what we call an unbalanced force. Let's break this law down by defining some key terms. Velocity is the speed of an object in a specified direction. An unbalanced force is an external force that changes the motion of an object. When an object is at rest or moving at a constant velocity, all the forces acting on it are balanced.
For example, my cup of coffee is resting on my kitchen table as I make this lesson. The force of gravity pulling down is balanced by the force of my kitchen table pushing up on my cup of coffee. Now, if I am to move my coffee, I must apply an external force to disrupt the balance. Thank goodness my muscles are strong enough to apply such a force so I can enjoy my cup of coffee. Ah, now that's good joe! Newton's first law of motion is also referred to as the law of inertia. Inertia is simply the resistance to change in motion. In short, objects tend to keep doing what they are already doing.
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According to first law of motiona)body acted on by no net force moves ...
According to Newton's 1st law ,a body in state of rest or in motion remains at rest or in motion unless acted upon by some external force
According to first law of motiona)body acted on by no net force moves ...
Explanation:
The first law of motion, also known as the law of inertia, states that a body acted on by no net force moves with constant velocity (which may be zero) and zero acceleration. This means that if there is no external force acting on an object, it will either remain at rest or continue to move at a constant speed in a straight line.
Key Points:
- No Net Force: For an object to experience no net force, the sum of all the forces acting on it must be zero.
- Constant Velocity: When an object moves with constant velocity, its speed and direction do not change. This means that the object is neither accelerating nor decelerating.
- Zero Acceleration: Acceleration is the rate at which an object's velocity changes. If the acceleration is zero, it means that the object's velocity remains constant.
Example:
To understand this concept, consider the example of a car moving on a straight road without any external forces acting on it. In this scenario, the car will continue to move at a constant speed in a straight line.
Importance:
The first law of motion is crucial in understanding the behavior of objects in the absence of external forces. It helps explain why objects at rest tend to remain at rest and why objects in motion tend to stay in motion.
Real-life Applications:
- When a person is riding a bicycle and stops pedaling, the bicycle gradually slows down and comes to a stop due to opposing forces like friction and air resistance. This is an example of a body acted on by external forces.
- When a satellite is in orbit around the Earth, it moves with constant velocity and zero acceleration. In this case, the gravitational force acting on the satellite provides the necessary centripetal force to keep it in orbit.
Conclusion:
According to the first law of motion, a body acted on by no net force moves with constant velocity (which may be zero) and zero acceleration. This law helps us understand the behavior of objects in the absence of external forces and is fundamental in studying motion and mechanics.
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