JEE Advanced 2016Paper 2
- Exam
- JEE Advanced
- Year
- 2016
- Paper
- Paper 2
- Subject
- Physics
- Chapter
- Current Electricity
JEE Advanced 2016 · Paper 2 · Physics · Current Electricity
Paragraph: Consider an evacuated cylindrical chamber of height h...
Paragraph:
Consider an evacuated cylindrical chamber of height having rigid conducting plates at the ends and an insulating curved surface as shown in the figure. A number of spherical balls made of a light weight and soft material and coated with a conducting material are placed on the bottom plate. The balls have a radius . Now a high voltage source is connected across the conducting plates such that the bottom plate is at and the top plate at Due to their conducting surface, the balls will get charged, will become equipotential with the plate and are repelled by it. The balls will eventually collide with the top plate, where the coefficient of restitution can be taken to be zero due to the soft nature of the material of the balls. The electric field in the chamber can be considered to be that of a parallel plate capacitor. Assume that there are no collisions between the balls and the interaction between them is negligible. (Ignore gravity)
Question: Which one of the following statements is correct?
Question: Which one of the following statements is correct?
Options
- AThe balls will bounce back to the bottom plate carrying the opposite charge they went up with
- BThe balls will execute simple harmonic motion between the two plates
- CThe balls will bounce back to the bottom plate carrying the same charge they went up with
- DThe balls will stick to the top plate and remain there
Correct answer
A. The balls will bounce back to the bottom plate carrying the opposite charge they went up with
Step-by-step solution
Balls placed on +ve plate become positive charge and move upward due to electric field. These balls on colliding with negative plate become negatively charged and move opposite to the direction of electric field.
Balls placed on +ve plate become positive charge and move upward due to electric field.
These balls on colliding with negative plate become negatively charged and move opposite to the direction of electric field.
Balls placed on +ve plate become positive charge and move upward due to electric field.
These balls on colliding with negative plate become negatively charged and move opposite to the direction of electric field.