At a Particular Time, a Radioactive Source a Has a Decay

question 59

Multiple Choice

At a particular time, a radioactive source A has a decay rate of 1.60 × 10¹¹ Bq and a half-life of 15.0 d, and a second source B has a decay rate of 8.50 × 10¹¹ Bq. Sources A and B have the same decay rate 45.0 d later. The half-life of B is

• A) 0.19 d.
• B) 8.3 d.
• C) 2.8 d.
• D) 5.4 d.
• E) 28 d.

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Definitions:

Visual Cortex

The segment of the cerebral cortex involved in visual information processing, found at the back part of the brain.

Size Constancy

The perceptual phenomenon where the perceived size of an object remains constant despite changes in the size of the object's image on the retina due to varying distances.

Perception

The cognitive process of interpreting and making sense of sensory information from the environment, influencing how one understands and interacts with the world.

Retina

A light-sensitive layer at the back of the eye that converts light into neural signals for visual processing by the brain.