Question

A small metallic ball is suspended in a uniform electric field by a thread. If high energy X-rays are made to fall on it , then:

• A. ball will be displaced in opposite direction to the direction of field
• B. ball will be displaced in the direction of field
• C. ball will remain in equilibrium state
• D. ball will start oscillating

Answer 1

Answer: (B)

ball will be displaced in the direction of field

High energy x-rays have the capability to knock off the outer shell as well as the inner shell electrons of the metal and thus makes it positively charged. Hence the positively charged metallic ball is attracted to the negative side of the field, i.e., the ball will be displaced in the field direction.