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Ch.1 - Chemical Tools: Experimentation & Measurement
Chapter 1, Problem 103

Among many alternative units that might be considered as a measure of time is the shake rather than the second. Based on the expression 'faster than a shake of a lamb's tail,' we'll define 1 shake as equal to 2.5 * 10-4 s. If a car is traveling at 55 mi/h, what is its speed in cm/shake

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Convert the speed from miles per hour to miles per second by dividing 55 mi/h by 3600 s/h.
Convert the speed from miles per second to centimeters per second by using the conversion factor 1 mile = 160934 cm.
Now, convert the speed from centimeters per second to centimeters per shake by using the conversion factor 1 shake = 2.5 \times 10^{-4} s.
Set up the conversion as a series of multiplication steps, ensuring that units cancel appropriately to leave you with cm/shake.
Perform the calculations step by step to find the final speed in cm/shake.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Unit Conversion

Unit conversion is the process of converting a quantity expressed in one set of units to another set of units. In this question, we need to convert the speed of the car from miles per hour (mi/h) to centimeters per shake (cm/shake). This involves using conversion factors to change both the distance and time units appropriately.
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Speed Calculation

Speed is defined as the distance traveled per unit of time. To find the speed in different units, we must first calculate the distance the car travels in a given time frame and then express that distance in the desired units. In this case, we will calculate how far the car travels in one shake and then convert that distance to centimeters.
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Understanding Time Units

Understanding time units is crucial for accurate calculations in physics and chemistry. A shake is defined as 2.5 x 10^-4 seconds, which is significantly shorter than a second. Recognizing this allows us to appropriately relate the speed of the car to the new time unit, ensuring that our final answer is in cm/shake.
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