Find the speed of the batsman and direction he takes (vectors)

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Homework Help Overview

The problem involves a scenario in cricket where a batsman hits a ball, and a fieldsman attempts to catch it. The context includes calculating the speed and direction of the fieldsman's run in relation to the ball's trajectory, utilizing concepts of vectors and angles.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the need to create variables for unknowns and explore relevant equations. Some mention using the sine rule and alternate angle rules to analyze the triangle formed by the paths of the ball and the fieldsman.

Discussion Status

Some participants have made attempts to solve the problem, with one noting a realization about the vector nature of side RS and its implications for determining direction and time. There is an ongoing exploration of angles and distances, but no consensus has been reached on the correct answers.

Contextual Notes

Participants express uncertainty about their calculations and the correctness of their answers, indicating that the problem may involve complex vector relationships and assumptions that need clarification.

Richie Smash
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Homework Statement


Hello, I havre problem here relevant to an image I will attach.

''A cricket ball hit by a batsman moves with a speed of 6m/s along a straight line path PQRS, as shown in the diagram. When the ball is at R, a fieldsman starts to run in a straight line from T with a speed of 10m/s.
Given that QRT = 25° and RT = 15m, determine by calculation or by drawing:
(a) the direction in which the fieldsman must run in order to retain the ball.
(b)the time he would take to reach the ball at s.

Homework Equations


V=distance/time

The Attempt at a Solution


I have absolutely no idea on this one I'm afraid.
The answer for part (a) in the backof the book is ''Bearing =79.7° ''

For (b), I drew a perpendicular line to QT. I then found angle RTQ which is 65°, then i worked out the angle from the perpendicular I drew by doing 90°-65° = 25°
From here i used the alternate angle rule to find angles RTS and RST which are 25°.

Then I found angle TRS which is 130° then used the sine rule to find side TS which I got to be 27.2 approx, then divided by 10 to find his speed, for which i got 2.72m/s.

Unfortunately that is also the wrong answer.
 

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Richie Smash said:
no idea
Standatd approach: create a variable for the unknown you wish to find and see what equations you can write. Some promising equations may involve other unknowns, such as the distance RS here. So create a variable for that and try to find a second equation involving it.
 
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I have figured it out, side RS was a vector itself of which I can find the angle necessary to give me a bearing of S from T to find the direction, and I can also use that same triangle with it's angle to fins the length of TS and then subsequently divide to find the time taken.
 
Richie Smash said:
I have figured it out, side RS was a vector itself of which I can find the angle necessary to give me a bearing of S from T to find the direction, and I can also use that same triangle with it's angle to fins the length of TS and then subsequently divide to find the time taken.
Well done.
 

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