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QJEEM24Phf5cf: JEE Main 2024 Physics - Class 11 JEEM24Phf5cf Solution: The co-ordinates of a particle moving in - plane are given by : …

The co-ordinates of a particle moving in xx - yy plane are given by : x=2+4t,y=3t+8t2x=2+4 \mathrm{t}, y=3 \mathrm{t}+8 \mathrm{t}^2 .

The motion of the particle is :

Multiple Choice Options

  • A uniform motion along a straight line.
  • B non-uniformly accelerated.
  • C uniformly accelerated having motion along a straight line.
  • D uniformly accelerated having motion along a parabolic path.

Step-by-Step Verified Solution

To determine the nature of the motion of the particle given by its coordinates in the xx - yy plane, we analyze the given equations for xx and yy in terms of time tt :

  • x=2+4tx = 2 + 4t
  • y=3t+8t2y = 3t + 8t^2

Firstly, the equation for xx is of the form x=x0+vtx = x_0 + vt , where x0=2x_0 = 2 is the initial position and v=4v = 4 is the constant velocity along the xx -axis. This suggests a uniform motion along the xx -axis because the velocity remains constant with time.

Secondly, the equation for yy is a second-degree polynomial in tt , which indicates a parabolic path. The presence of the t2t^2 term ( 8t28t^2 ) signifies acceleration since the position along the yy -axis is changing at a rate that itself changes over time.

The equation for yy can show two types of motion depending on the terms:

  1. If it was of the form y=y0+vty = y_0 + vt , it would indicate uniform motion.
  2. If it was of the form y=y0+vt+12at2y = y_0 + vt + \frac{1}{2}at^2 , where aa would represent acceleration, it would indicate uniformly accelerated motion. The presence of the 8t28t^2 term here plays a similar role, indicating that the motion is uniformly accelerated in the yy -direction due to the constant acceleration implied by this term.

Since the motion in the yy direction is determined by a quadratic equation, and the path of the particle depends on both the xx and yy coordinates, the motion of the particle is not along a straight line but rather follows a parabolic path due to the quadratic (second-degree) dependence on time in the yy -coordinate.

Additionally, the acceleration is not changing with time, as deduced from the constant coefficient of the t2t^2 term in the yy equation, indicating uniform acceleration. Therefore, the motion is uniformly accelerated and follows a parabolic path.

Hence, the correct answer is:

Option D: uniformly accelerated having motion along a parabolic path.

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