Help with 2 simple highschool physics Problem

AI Thread Summary
To average 60 km/h over a 90-km trip after averaging 40 km/h for the first 40 km, the required velocity for the remaining distance can be calculated by determining the time spent and time remaining. For the second problem, Juanita, walking at 4.5 km/h for 45 minutes, will have covered a certain distance, and the speed needed to catch up in one hour can be derived from her total distance. The key is to use the formula v = d/t to find the necessary velocities. Understanding the time and distance relationships is crucial for solving both problems. These calculations will provide the answers needed for the homework questions.
pamba
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:redface: I am really tired and i can't sem to thik right. Please help with these 2 questions




Homework Statement



1. If you must average 60 km/h for a 90-km trip, and only average 40 km/h for the first 40 km, wha velocity must you average the rest of the way?

2. Juanita left on a walk 45 min ago. She is traveling a 4.5km/h. How fast must you travel to catch up to her in 1.0 h?


Homework Equations



v: d/t


The Attempt at a Solution



??
 
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1. How much time would it take if you were going 90km at 60km/h?
How much time have you spent going 40km/h?
So how fast will you have to go for the next 50km in the time you have left?
 
#2

As for #2, how much has Juanita traveled in 45 minutes?
How much will she have traveled once you have caught up to her? (in 1 hour and 45 mins)

that should help
qk
 

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