Kinematics Problem Homework Help

AI Thread Summary
To solve the kinematics problem, the car must average 47 km/h over a 99 km journey. It travels the first 49.5 km at 38 km/h, which requires calculating the time taken for that segment. The remaining distance must be covered at a speed that compensates for the slower initial speed to achieve the desired average. The equation 47 = 0.5(38 + x) indicates the need to find the second segment's speed, x, while considering the total time for the journey. Clarification on the relevant equations and specific questions would enhance the assistance provided.
mpoole
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1. A car making a 99-km journey travels 38 km/h for the first 49.5 km. How fast must it go during the second 49.5 km to average 47 km/h?



2. Homework Equations ?



3. 47=.5(38+x)
 
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You need to consider time in your solution. For example, if the average speed is 47 km/h and the distance traveled is 99 km, how long should this take to occur?
 
Welcome to PF;
You didn't provide a lot of information - i.e. the "relevant equations" section is not filled in.
It is difficult to know what sort of reply will best fit your need.
From the unfinished calculation in section 3, we can make a guess but we could guess wrong.

Did you have a specific question for us or did SteamKing manage to cover it?
 
Thread 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

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