Background: One reason radiation is dangerous is that it can’t be detected with the senses. You normally can’t see it, smell it, hear it, or feel it. Fortunately, there are devices such as Geiger counters that can detect radiation. A Geiger counter, like the one in Figure below , has a tube that contains atoms of a gas. If radiation enters the tube, it turns gas atoms to ions that carry electric current. The current causes the Geiger counter to click. The faster the clicks occur, the higher the level of radiation.

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In Fukushima would a Geiger counter click faster or slower than Hiroshima?
Answer: faster

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In Hiroshima would a Geiger counter click faster or slower than Fukushima?
Answer: slower

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In which city a Geiger counter would click faster, Fukushima or Hiroshima?
Answer: Fukushima

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In which city a Geiger counter would click slower, Fukushima or Hiroshima?
Answer: Hiroshima

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In which city a Geiger counter would start clicking, Hiroshima or Tokyo?
Answer: Hiroshima

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In which city a Geiger counter would not start clicking, Hiroshima or Tokyo?
Answer: Tokyo

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In which city a Geiger counter would produce electirc current, Fukushima or Tokyo?
Answer: Fukushima

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In which city a Geiger counter would not produce electirc current, Fukushima or Tokyo?
Answer: Tokyo

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In which city the gas inside a Geiger counter would be ionized, Hiroshima or Tokyo?
Answer: Hiroshima

Situation: David was visiting Japan. First, he went to Fukushima where the recent nuclear plant disaster happened. He found the city still had very high radiation. Then he visited Hiroshima. He found that Hiroshima had some low radiation. Finally, he visited the capital city Tokyo. He found that Tokyo did not have any radiation.

Question: In which city the gas inside a Geiger counter would not be ionized, Hiroshima or Tokyo?
Answer: Tokyo