JEE Advanced 2011Paper 1
- Exam
- JEE Advanced
- Year
- 2011
- Paper
- Paper 1
- Subject
- Physics
- Chapter
- Motion in One Dimension
JEE Advanced 2011 · Paper 1 · Physics · Motion in One Dimension
Paragraph: Phase space diagrams are useful tools in analyzing all...
Paragraph:
Phase space diagrams are useful tools in analyzing all kinds of dynamical problems. They are especially useful in studying the changes in motion as initial position and momentum are changed. Here we consider some simple dynamical systems in one-dimension. For such systems, phase space is a plane in which position is plotted along horizontal axis and momentum is plotted along vertical axis. The phase space diagram is curve in this plane. The arrow on the
curve indicates the time flow. For example, the phase space diagram for a particle moving with constant velocity is a straight line as shown in the figure. We use the sign convention in which position or momentum upwards (or to right) is positive and downwards (or to left) is negative.
Question: The phase space diagram for a ball thrown vertically up from ground is
Question: The phase space diagram for a ball thrown vertically up from ground is
Options
- A
- B
- C
- D
Correct answer
D.
Step-by-step solution
Momentum is first positive but decreasing. Displacement (or say position). is initially zero.
It will first increase. At highest point, momentum is zero and displacement is maximum. After that momentum is downwards (negative) and increasing but displacement is decreasing. Only (d) option satisfies these conditions.
Analysis of Question
(i) Question is simple.
(ii) Since all the graphs given in question are parabolic type, we need not to check the mathematical part of the question.