Assuming one nerve impulse must end before another can begin, what is the maximum firing rate of a nerve in impulses per second? SOLUTION: One nerve impulse lasts for .
(a) Calculate the number of cells in a hummingbird assuming the mass of an average cell is ten times the mass of a bacterium. (b) Making the same assumption, how many cells are there in a human? SOLUTION: a) The mass of a hummingbird is , while the mass of a cell is . The number of … Continue reading College Physics Problem 1.35
(a) What fraction of Earth’s diameter is the greatest ocean depth? (b) The greatest mountain height? SOLUTION: a) The greatest ocean depth is , while the earth's diameter is . b) The highest mountain is also roughly .
Approximately how many atoms thick is a cell membrane, assuming all atoms there average about twice the size of a hydrogen atom? SOLUTION: The cell membrane is m while the hydrogen atom is m. The number of atoms in the cell membrane is
Calculate the approximate number of atoms in a bacterium. Assume that the average mass of an atom in the bacterium is ten times the mass of a hydrogen atom. (Hint: The mass of a hydrogen atom is on the order of and the mass of a bacterium is on the order of .) SOLUTION: … Continue reading College Physics Problem 1.32
How many times longer than the mean life of an extremely unstable atomic nucleus is the lifetime of a human? (Hint: The lifetime of an unstable atomic nucleus is on the order of .) [toggle] The lifetime of a human is , while the lifetime of the unstable atomic nucleus is . Therefore, human lifetime is … Continue reading College Physics Problem 1.31
A generation is about one-third of a lifetime. Approximately how many generations have passed since the year 0 AD? [toggle] We are looking for the generations passed in the history. The general assumptions are: There are in 1 history In 1 generation, there is 1/3 of a lifetime. In half a lifetime, there are Therefore, the … Continue reading College Physics Problem 1.30
How many heartbeats are there in a lifetime? SOLUTION: The general assumptions: There is 1 heartbeat in 1 second In half a lifetime, there are seconds. Therefore, in a lifetime, the number of heartbeats is