Calculating Cyclist Speed: 10 Secs and 5 Secs

  • Thread starter Thread starter Izekid
  • Start date Start date
  • Tags Tags
    Speed
AI Thread Summary
The cyclist's average speed is 1.8 m/s, with a top speed of 3.6 m/s reached in 10 seconds. To determine the distance covered in the last 5 seconds, one can use the formula for distance based on average speed. The discussion suggests that if the top speed is double the average speed, the cyclist likely started from rest, indicating a constant acceleration model. The total distance covered in the first 10 seconds can be calculated as the area of a triangle under the velocity vs. time graph. Understanding these calculations allows for estimating the cyclist's performance over the last segment of the race.
Izekid
Messages
40
Reaction score
0
The cyclist got a average speed of 1,8m/s and a top speed of 3,6sek
The time is 10 sek.
How do I get to know how long will the cyclist cycle the last 5 sek of the 10 sek. Can i conclude that with my formula?

Please help me
 
Physics news on Phys.org
If you mean that the top speed is 2 times the average speed, then
(in first approximation of constant acceleration) the lowest speed was zero.
So the graph of velocity vs time is through the origin, straight-line.

How far did he go in the whole 10 seconds? (½ vmax tmax)
this is the area of the triangle "under the curve" v vs t .

How far would he go, in the last half of the race?
(OK, what would his average speed be during this half?)
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top