Calculating Average Speed and Velocity for a Commuting Student

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SUMMARY

The discussion focuses on calculating the average speed and average velocity of a commuting student who drives to school and back. The student travels at an average speed of 42.0 km/h, initially driving for 22.0 minutes before returning home for 8.0 minutes to retrieve forgotten homework. The total distance covered is 84 km (42 km to school and 42 km back), while the total time taken is 38 minutes (22 minutes to school, 8 minutes searching, and 8 minutes back). The average speed for the entire trip is 132 km/h, and the average velocity is 0 km/h due to the net displacement being zero.

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  • Understanding of average speed and average velocity concepts
  • Familiarity with basic kinematic equations
  • Knowledge of scalar vs. vector quantities
  • Ability to perform unit conversions and time calculations
NEXT STEPS
  • Study the differences between scalar and vector quantities in physics
  • Learn how to apply kinematic equations in real-world scenarios
  • Explore problems involving average speed and average velocity
  • Investigate the impact of direction on displacement calculations
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This discussion is beneficial for physics students, educators, and anyone interested in understanding the principles of motion, particularly in calculating average speed and velocity in practical situations.

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Homework Statement



A commuting student leaves home and drives to school at an average speed of 42.0 km/h. After 22.0 min she realizes that she has forgotten her homework and returns home to get it at the same average speed. It takes 8.0 min to find the report, after which the trip to school 42.0 km away to the east is resumed at the same speed as before.
What is the average speed for the entire trip ? What is the average velocity for the entire trip?

Homework Equations



speed av= total distance/delta t (change in t)
v av (average velocity)=delta x/delta t (change in x, change in t)

The Attempt at a Solution



I've tried numerous things with no success. Please help!
 
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Remember that speed is scalar and velocity is vector. If you wall 10 meters forward and then turn back and return to your original spot then you will have traveled a total distance of 20 meters. But your total displacement is 0. Speed is associated with distance and velocity is associated with displacement.
 
ok so for her total dispacement she basically only went 42 km since she had to turn around the first time correct? but I am having trouble with the time would her total time be 30 mins since she had to turn around and then look for the report?
 

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