Respuesta :
Answer:
The time taken to complete her run is 1.9 hr.
Explanation:
Speed is a scalar quantity and it is defined as the ratio of distance covered to the time taken to cover that distance. As distance is also a scalar quantity, so the directions given in the problem can be ignored. Thus, the distance covered by the jogger is the sum of kilometers given in problem.
Distance covered = 6+5+4 = 15 km
And the speed is given as 8 km/hr.
So the time taken will be ratio of distance to speed.
So the jogger will take 1.9 hr to complete her run.
- The time taken by the jogger to complete the run is 1.875 hours
- The average velocity of the runner is 5.96 km/h
The given parameter:
initial position of the Jogger = 6 km north
second position of the Jogger = 5 km east
final position of the Jogger, = 4 km north
average speed of the jogger = 8km/h
To find:
- the total time taken by the runner
- the average velocity of the runner
Calculate the time taken for each position:
[tex]time = \frac{distance }{speed} \\\\t_1 = \frac{6 \ km}{8 \ km/h} = 0.75 \ hr\\\\t_2 = \frac{5 \ km}{8 \ km/h} = 0.625 \ hr\\\\t_3 = \frac{4 \ km}{8 \ km/h} = 0.5 \ hr\\\\[/tex]
Total time = 0.75 hr + 0.625 hr + 0.5 hr = 1.875 hr
The time (hour, minutes and seconds) = 1 hour, 52 minutes, 30 seconds
The average velocity is calculated as:
[tex]average \ velocity = \frac{displacement }{time}[/tex]
The displacement is the shortest point between the initial position and the final position.
Q
↑
↑ 4km
↑
↑→ → → →5km→ → →
↑ 6km |
↑ |
p -----------------------| Y
The line PQ is the displacement = hypotenuse side
The line PY = base of the right triangle = 5 km
The line YQ = height of the triangle = 4 km + 6km = 10 km
The line PQ is calculated as:
[tex]PQ^2 = 5^2 + 10^2\\\\PQ^2 = 125\\\\PQ = \sqrt{125} \\\\PQ = 11.18 \ km[/tex]
The average velocity is calculated as:
[tex]V = \frac{11.18}{1.875} = 5.96 \ km/hr\\\\V(m/s) = \frac{5.96}{3.6} = 1.66 \ m/s[/tex]
Learn more here: https://brainly.com/question/862972
