Starting from the front door of a ranch house, you walk m due east to a windmill, turn around, and then slowly walk m west to a bench, where you sit and watch the sunrise. It takes you s to walk from the house to the windmill and then s to walk from the windmill to the bench. For the entire trip from the front door to the bench, what are your (a) average velocity? (b) average speed?
Ch 02: Motion Along a Straight Line
2장, 문제 3
You normally drive on the freeway between San Diego and Los Angeles at an average speed of km/h ( mi/h), and the trip takes h and min. On a Friday afternoon, however, heavy traffic slows you down and you drive the same distance at an average speed of only km/h ( mi/h). How much longer does the trip take?
검증된 단계별 안내1
First, convert the time of the normal trip from hours and minutes to hours. The trip takes 1 hour and 50 minutes, which is equivalent to 1 + 50/60 hours.
Calculate the distance of the trip using the formula for distance: \( \text{Distance} = \text{Speed} \times \text{Time} \). Use the normal speed of 105 km/h and the converted time from step 1.
Now, calculate the time taken for the trip on Friday afternoon using the formula \( \text{Time} = \frac{\text{Distance}}{\text{Speed}} \). Use the distance calculated in step 2 and the reduced speed of 70 km/h.
Convert the time taken on Friday afternoon from hours to hours and minutes for easier comparison with the normal trip time.
Finally, find the difference in time between the normal trip and the Friday afternoon trip by subtracting the normal trip time from the Friday afternoon trip time. This will give you how much longer the trip takes.

비슷한 문제에 대한 검증된 영상 답변:
이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
4m주요 개념
질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.
Average Speed
Average speed is defined as the total distance traveled divided by the total time taken to travel that distance. It is a scalar quantity and is typically expressed in units such as kilometers per hour (km/h) or miles per hour (mi/h). Understanding average speed is crucial for calculating travel time over a given distance.
추천 영상:
가이드 코스
Solving Constant and Average Velocity Problems
Distance-Time Relationship
The distance-time relationship is a fundamental concept in kinematics, which states that distance equals speed multiplied by time (d = vt). This relationship allows us to calculate one of these variables if the other two are known, making it essential for solving problems involving travel time and speed.
추천 영상:
가이드 코스
Relationships Between Force, Field, Energy, Potential
Unit Conversion
Unit conversion involves changing a measurement from one unit to another, such as converting time from hours and minutes to just hours. This is important for ensuring consistency in calculations, especially when dealing with different units of speed and time, as seen in this problem where time is given in hours and minutes.
추천 영상:
가이드 코스
Unit Conversions
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