Which of the following would be a typical application of gamma radiation? A) Heating objects. B) Killing cells and organisms. C) Producing fluorescence. Or D) transmitting signals between Earth and space.
We’ve got four possible answers here. So, let’s go through them in order and think about whether gamma radiation can be used for each of these applications. First up, heating objects. When we talk about radiation producing heat, we’re almost always talking about infrared radiation. Absorbing infrared radiation will increase the temperature of any object. And any object with a temperature above absolute zero will emit infrared radiation as well.
The hotter the object, the more infrared radiation it will emit, which can cause it to heat up other objects. In fact, infrared radiation is the main mechanism by which the sun heats up the Earth. Now, all kinds of electromagnetic radiation actually have some heating effect. But this effect is much more significant with infrared. So, we can rule out option A as this isn’t a typical application of gamma radiation.
Next, option B, killing cells and organisms. Now, out of all electromagnetic radiation, gamma radiation has the most energy. This makes it very dangerous to living organisms. If a gamma ray strikes a cell in an organism, then the energy contained within it can be enough to break apart DNA or proteins or other molecules that the cell depends on to live. In fact, gamma radiation is often used in hospitals to sterilize medical equipment by killing bacteria. So, B is a correct answer; killing cells and organisms is a typical application of gamma radiation.
Now, let’s just go through the other two answers as well to make sure that they’re not applications of gamma radiation. Option C is producing fluorescence. Fluorescence is where a material absorbs some kind of radiation and then gives off visible light. And fluorescence most commonly occurs when objects are exposed to ultraviolet radiation.
Now, ultraviolet radiation is invisible to humans. But if it shines on a fluorescent material, then that material will give off visible light. This is the same mechanism used by some fish and other animals that have particularly bright coloring. Fluorescent pigments in their scales absorb invisible ultraviolet radiation from the sun, which is then given off as visible light. Which is really cool, but nothing to do with gamma radiation.
That just leaves us with option D, transmitting signals between Earth and space. Now, transmitting signals from Earth to space and back again is crucial for things like satellite communication, which enables us to communicate between parts of the Earth’s surface that are far away from each other. And we also need to be able to do this to communicate with spacecraft that we send out into space.
When sending signals into space, we always use certain frequencies of microwaves and radio waves because these can pass through the atmosphere more effectively than other kinds of radiation. So, option D also has nothing to do with gamma radiation. The correct answer is B. A typical application of gamma radiation is killing cells and organisms.