NTA Abhyas 2020
- Exam
- NTA Abhyas
- Year
- 2020
- Subject
- Physics
- Chapter
- Center of Mass, Momentum and Collision
NTA Abhyas 2020 · Physics · Center of Mass, Momentum and Collision
Two particles of equal mass have velocities → v 1 = 4 ^ i ^ -1 and...
Two particles of equal mass have velocities \overset{→}{v}1 = 4\overset{^}{i}\mathrm\mathrm\mathrm\mathrm\mathrm\mathrm\mathrm\mathrm\mathrm\mathrm\mathrm{ms}^{-1} and \overset{→}{v}2 = 4\overset{^}{j}{ ms}^{- 1}. First particle has an acceleration \overset{→}{a}1 = \left(5\overset{^}{i} + 5\overset{^}{j}\right){ ms}^{- 2}, while the acceleration of the other particle is zero. The centre of mass of the two particles moves in a path of
Options
- AStraight line
- BParabola
- CCircle
- DEllipse
Correct answer
A. Straight line
Step-by-step solution
Since,
= \dfrac{1}{2} \times (4\overset{^}{i} + 4\overset{^}{j} )
= 2 ( \overset{^}{i} + \overset{^}{j} )
Similarly
= \dfrac{1}{2} \times (5\overset{^}{i} + 5\overset{^}{j} + 0 )
= \dfrac{5}{2} ( \overset{^}{i} + \overset{^}{j} )
Both and are parallel
Centre of mass will move in a straight line because velocity and acceleration of centre of mass are in same direction.
= \dfrac{1}{2} \times (4\overset{^}{i} + 4\overset{^}{j} )
= 2 ( \overset{^}{i} + \overset{^}{j} )
Similarly
= \dfrac{1}{2} \times (5\overset{^}{i} + 5\overset{^}{j} + 0 )
= \dfrac{5}{2} ( \overset{^}{i} + \overset{^}{j} )
Both and are parallel
Centre of mass will move in a straight line because velocity and acceleration of centre of mass are in same direction.