Question

A plane travels 350 km south along a straight path with an average velocity of 125 km/h to the south. The plane has a 30 minute layover, and then travels 220 km south with an average velocity of 115 km/h to the south. What is the average velocity for the trip?. a.120 km/hr to the south. b.110 km/hr to the south. c. 121 km/hr to the south. d. need more information

Answer 1

Average Velocity = Total Displacement / Total time

1st part of journey, 350 km at velocity 125 km/h

Time = 350 / 125 = 2.8 hours.

2nd part of journey, 220 km at velocity 115 km/h

Time = 220 / 115 = 1.9 hours


Average Velocity = Total Displacement / Total time

= (350 + 220) / (2.8 + 1.9)

= 570 / 4.7 ≈ 121.3 km/hr

Average Velocity ≈ 121 km/hr due south.

Option C.

Answer 2

b)
`v = 110 km/h` Towards South

Step-by-step explanation:

First plane moves with uniform velocity of 125 km/h towards South

so time taken by the plane to move 350 km is given as

`t_1 = (350)/(125)`

`t_1 = 2.8 hours`

Now it has a layover time of 30 min

then it moves with uniform velocity of 115 km/h towards South

so time taken by the plane to move 220 km is given as

`t_2 = (220)/(115)`

`t_2 = 1.9 hours`

Now we have total displacement of the plane is

`d = 220 + 350`

`d = 570 km`

total time of the journey is given as

`T = 2.8 + 0.5 + 1.9`

`T = 5.21 h`

now average velocity is given as

`v = (d)/(T)`

`v = (570)/(5.21)`

`v = 110 km/h` Towards South