A radioactive isotope has an activity of 8.02×10^4 Bq initially. After 3.55 hours the activity is 4.81×10^4 Bq. a. What is the half-life of the isotope?
b. What is the activity after an additional 3.55 hours?

The two required components for a generator

A6.0-kilogram cart initially traveling at 4.0 meters per second east accelerates uniformly at 0.50 meter per second squared east for 3.0 seconds. what is the speed of the cart at the end of this 3.0 second interval? (1) 1.5 m/s (3) 3.0 m/s (2) 5.5 m/s (4) 7.0 m/s

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656(red) and 486 (blue). light from a hydrogen lamp illuminates a diffraction grating with 500 lines per mm, and the light is observed on a screen 1.50 behind the grating. what is the distance between the first-order red and blue fringes?