﻿ A train is moving southwards at a speed of 30 ms–1. A monkey is running northwards on the roof of the train with a speed of 5ms–1. What is the velocity of the monkey as obserced by a person standing on the ground? : Kaysons Education

# A Train Is Moving Southwards At A Speed Of 30 Ms–1. A Monkey Is Running Northwards On The Roof Of The Train With A Speed Of 5ms–1. What Is The Velocity Of The Monkey As Obserced By A Person Standing On The Ground?

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## Question

### Solution

Correct option is

25 ms–1 in the southward direction

Suppose we choose the direction from south to north as the positive direction. Then the velocity of the train moving southwards = –30 ms–1. Velocity of the monkey running northwards = +5 ms–1. Therefore, the velocity of the monkey as observed by a person in the ground = –30 + 5 = –25 ms–1. The negative sign indicates that the direction of this velocity is southwards.

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