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Brad stands 6km west of a flagpole, and runs towards it with a speed of 9km/hr. Pitt stands 5km east of the flagpole, and runs toward it with a speed of 8km/hr. At what displacement from the flagpole are they when they meet?

1 Answer

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To solve this problem, we can use the concept of relative motion.

Let's break down the information given:

Brad starts 6 km west of the flagpole.

Brad's speed is 9 km/hr.

Pitt starts 5 km east of the flagpole.

Pitt's speed is 8 km/hr.

When they meet, their combined displacement from the flagpole will be equal. We'll assume that both Brad and Pitt started at the same time.

Let's say they meet after time "t" hours.

Distance Brad travels = Brad's speed * t = 9t km (since he's moving towards the flagpole)

Distance Pitt travels = Pitt's speed * t = 8t km (since he's moving towards the flagpole)

The net displacement of Brad from the flagpole is initially 6 km west and then 9t km east (due to his movement).

The net displacement of Pitt from the flagpole is initially 5 km east and then 8t km west (due to his movement).

Since their net displacements are equal when they meet:

6 + 9t = 5 + 8t

Subtracting 8t from both sides:

t = 1

Now that we know they meet after 1 hour, we can find their displacements from the flagpole at that time:

Brad's displacement = 6 km (initial westward displacement) + 9 km (distance covered in 1 hour) = 15 km east of the flagpole.

Pitt's displacement = 5 km (initial eastward displacement) + 8 km (distance covered in 1 hour) = 13 km west of the flagpole.

So, when they meet, Brad is 15 km east of the flagpole, and Pitt is 13 km west of the flagpole. The distance between them is the sum of their displacements:

Distance between them = Brad's displacement + Pitt's displacement = 15 km + 13 km = 28 km from the flagpole.

User Sangram Mohite
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