If displacement is proportional to the square of time then acceleratio...
The first two equations of motion each describe one kinematic variable as a function of time. ... Velocity is directly proportional to time when acceleration is constant (v ∝ t). Displacement is proportional to time squared when acceleration is constant (∆s ∝ t2).
Here, displacement,s=kt^2, where k is constant of proportionality. The body starts from rest.
Velocity,v=ds/dt=2kt. So velocity goes on increasing linearly with time. But when body will enter relativistic region such simple relation will not hold.
The acceleration, a=dv/dt=2k which is constant. So this is the motion with uniform acceleration. You can compare s=kt^2 with equation of motion s=(1/2)at^2.
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If displacement is proportional to the square of time then acceleratio...
Explanation:
Displacement and Time Relationship:
When it is stated that displacement is proportional to the square of time, it means that the displacement (d) is directly proportional to the square of the time (t^2). Mathematically, this relationship can be expressed as:
d ∝ t^2
This indicates that as the time increases, the displacement will increase at a rate proportional to the square of that time.
Acceleration and Displacement Relationship:
Acceleration (a) is the rate at which the velocity of an object changes with time. It is defined as the change in velocity divided by the change in time. Mathematically, acceleration can be expressed as:
a = (v - u) / t
Where 'v' is the final velocity, 'u' is the initial velocity, and 't' is the time taken.
Uniform Acceleration:
Uniform acceleration refers to a situation where the acceleration of an object remains constant over a given time period. This means that the object's velocity changes by the same amount in equal intervals of time.
Relationship between Displacement and Uniform Acceleration:
If the displacement is directly proportional to the square of time (d ∝ t^2), then its derivative, velocity, would be directly proportional to time (v ∝ t). Taking the derivative of velocity, which is acceleration, we get:
a = dv/dt
Since v ∝ t, the derivative of v with respect to t is a constant value. Therefore, the acceleration remains constant (uniform) when the displacement is proportional to the square of time.
Example:
Let's consider a scenario where an object starts from rest (u = 0) and undergoes uniform acceleration. If the displacement of the object is given by d = kt^2, where k is a constant, we can find the acceleration.
Taking the derivative of displacement with respect to time, we get:
v = d/dt (kt^2) = 2kt
Now, taking the derivative of velocity with respect to time, we get:
a = d/dt (2kt) = 2k
As we can see, the acceleration is a constant value of 2k, indicating uniform acceleration.
In conclusion, when displacement is proportional to the square of time, the acceleration is uniform because the derivative of velocity with respect to time is constant. This relationship holds true in scenarios where the object's displacement follows a quadratic function of time.
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