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semc
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hmm...i was wondering is there any conditions for the use of Newton's second law?
semc said:hmm...i was wondering is there any conditions for the use of Newton's second law?
semc said:i don't reali know how to put it in words but erm...we do not need a varying mass to use F=dmv/dt right?
An easy calculus problem, but a tricky physics problem. Suppose there is a railroad car coasting with speed V on a straight horizontal track without any rolling friction. The car is full of water and has initial mass Mo and velocity Vo. As the car rolls, the water in the tank leaks out of a hole in the bottom of the tank at a rate we can assume to be constant (maybe the hole gets a little bigger as the water level drops). So the mass M of the car is changing at a constant rate. The only forces acting on the car are gravity and the normal force, both of which are perpendicular to the motion. What happens to the velocity of the car?radou said:Well, if the mass is not constant, then you have [tex]\vec{F}=\frac{d}{dt}(m\vec{v})=\frac{dm}{dt}\vec{v}+m\frac{d\vec{v}}{dt}[/tex].
Newton's 2nd Law, also known as the Law of Force and Acceleration, states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. This can be mathematically represented as F=ma, where F is force, m is mass, and a is acceleration.
In order for Newton's 2nd Law to be applicable, the object must be experiencing a net force, meaning there is more than one force acting on it. The object must also have a non-zero mass and be in a state of acceleration, either speeding up or slowing down.
Newton's 2nd Law is used in a variety of everyday situations, such as driving a car, throwing a ball, or riding a bike. It helps us understand how different forces, such as friction and gravity, affect the motion of objects and how we can apply forces to achieve the desired acceleration.
Mass is a measure of the amount of matter an object contains, while weight is a measure of the force of gravity acting on an object. In relation to Newton's 2nd Law, mass is constant and does not change, while weight can vary depending on the strength of the gravitational force.
Yes, Newton's 2nd Law can be applied to objects in outer space as long as there is a net force acting on the object. In the absence of air resistance and other external forces, an object's mass and the force acting on it will determine its acceleration. This is why astronauts experience weightlessness in space, as there is no gravitational force acting on them to cause acceleration.