Radioactive dating gcse
Radioactive sources (most commonly Technetium-99 or sometimes Iodine-123) can be used by doctors to find out if different organs in our bodies are working properly (eg. Doctors can inject a small amount of radioactive substance into a patient's body.This substance is carried by the blood to the organ, eg the kidneys or the thyroid gland, that the doctor wants to examine. Tracers are chosen which will concentrate in the part of the body to be investigated, and the tracer's radiation will also be concentrated there.Drawing of heads of cave lions in the Chauvet cave (south-east France).Dated by radiocarbon dating of the charcoal used to produce the drawings to around 36,000 years ago. Clottes.] The amount of carbon-14 in the atmosphere has not changed in thousands of years.
Sterilising medical equipment and food Surgical instruments are sterilised using high doses of gamma radiation.The Americium emits alpha particles that ionise the air between the two charged metal plates, resulting in a small current flowing.If smoke particles enter the alarm, they (1) gather up and neutralise the ions and (2) absorb some of the alpha particles, so both the ionisation rate and the number of ions gets less, the current reduces, a microchip notices this and triggers the alarm.Some of the isotope is injected into the pipe and then detected with a Geiger counter above ground.Radiotherapy (killing cancer cells) Although ionising radiation can cause cancer, high doses of gamma (or X-ray) radiation can target and kill cancerous cells. About 40% of people with cancer undergo radiotherapy as part of their treatment.