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Understanding how to calculate average speed is crucial in solving this physics problem. Average speed is defined as the total distance traveled divided by the total time taken. It can be expressed using the formula: \[ \text{Average Speed} = \frac{\text{Total Distance}}{\text{Total Time}} \] In the problem, you're given two scenarios with different speeds for the same distance. Initially, the average speed is 105 km/h for the journey, allowing the calculation of total distance when multiplied by the total travel time of 2 hours and 20 minutes, converted into hours. On the second occasion, the average speed is reduced to 70 km/h due to heavy traffic.

• Average speed helps understand how consistent velocity is throughout the trip.
• It's useful for predicting travel times under different conditions.

Recognizing the role of average speed is essential to find out how slower speeds impact travel time.

In physics problems like this, time conversion is a key skill. We often need to convert time given in minutes to hours for consistent use in formulas. Here's a step-by-step explanation of how we achieve this:Given the original time of 2 hours and 20 minutes, first convert the 20 minutes into a fractional hour. Since 1 hour equals 60 minutes, you convert minutes to hours by dividing the number of minutes by 60. Thus,\[ 20 \text{ minutes} = \frac{20}{60} = \frac{1}{3} \text{ hours} \]Adding this to the 2 hours results in:\[ 2 + \frac{1}{3} = \frac{7}{3} \text{ hours} \]Moving all time measures to the same unit simplifies calculations.

• This method is especially useful when calculating with speeds given in terms of km/h or mi/h.
• Ensures consistency and accuracy in further travel time or distance computation calculations.

Proper time conversion prevents errors and facilitates seamless calculations.

Distance calculation is an essential part of solving this problem. We use the formula: \[ \text{Distance} = \text{Speed} \times \text{Time} \] In our scenario, the distance is calculated during the first journey using the known average speed of 105 km/h and the total converted time of \(\frac{7}{3}\) hours:\[ \text{Distance} = 105 \frac{\text{km}}{\text{h}} \times \frac{7}{3} \text{h} = 245 \text{ km} \]Then, when the speed is reduced to 70 km/h due to traffic, the same distance of 245 km is used in our formula to determine the new travel time:\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} = \frac{245 \text{ km}}{70 \frac{\text{km}}{\text{h}}} = 3.5 \text{ hours} \]

• Ensures accurate travel predictions by relating speed and time.
• Facilitates comparison between different travel speeds for the same route.

Accurately calculating distance is crucial for resolving time-related inquiries and understanding journey dynamics.