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rudransh verma
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I was wondering how the second equation of motion produces negative displacements ##s= ut+\frac 12 at^2## . Is ##\frac12 at^2## kind of distance operator?
You can get a negative displacement if ##u## (the initial velocity) is negative.rudransh verma said:I was wondering how the second equation of motion produces negative displacements ##s= ut+\frac 12 at^2## . Is ##\frac12 at^2## kind of distance operator?
So ##u+\frac12at## is average velocity and when this is -ve then s is also -ve. The eqn of ##s=ut+\frac12at^2## is same as ##{x_2}-{x_1}= {v_{avg}}t##.jbriggs444 said:As I understand @DrClaude, he takes the viewpoint that for constant acceleration, the average velocity is attained halfway through the time interval, so it is given by u+12at. Multiply average velocity by the total time interval t to get s=(u+12at)t.
Yes -- if we take ##t## as positive. But the equation still holds for ##t## negative if the constant acceleration was constant in the past.rudransh verma said:So ##u+\frac12at## is average velocity and when this is -ve then s is also -ve.
Here I am not sure whether there is a language difficulty or whether you are contemplating a non-constant [1 dimensional] velocity and invoking the mean value theorem. Yes, under these conditions, I believe that the mean value theorem guarantees that the average velocity be attained as an instantaneous velocity somewhere within the time interval.rudransh verma said:u is the initial velocity and due to a acceleration somewhere in time interval t ##{v_{avg}}## is achieved.
Constant acceleration. Yes!jbriggs444 said:Here I am not sure whether there is a language difficulty or whether you are contemplating a non-constant but continuous acceleration and invoking the mean value theorem.
The second equation of motion, also known as the SUVAT equation, is a mathematical formula that relates an object's displacement, initial velocity, acceleration, and time. It is commonly used in kinematics to calculate the final velocity or displacement of an object.
The second equation of motion is derived from the basic principles of calculus and Newton's laws of motion. It is based on the concept of constant acceleration, where the acceleration of an object remains constant throughout its motion.
The variables in the second equation of motion are displacement (s), initial velocity (u), acceleration (a), and time (t). These variables are represented by the letters "s", "u", "a", and "t" respectively, and are measured in units of distance, velocity, acceleration, and time.
The second equation of motion is used in various real-life applications, such as predicting the landing point of a projectile, calculating the speed of a falling object, and determining the stopping distance of a moving vehicle. It is also used in sports science to analyze the performance of athletes and in engineering to design efficient machines and structures.
Yes, the second equation of motion has some limitations. It assumes that the acceleration of an object remains constant, which may not always be the case in real-life situations. It also does not take into account external factors such as air resistance and friction, which can affect the motion of an object. Therefore, it is important to use this equation with caution and consider other factors that may influence the motion of an object.