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Sahay Sir > Question Answers > NCERT Exemplar Class 11 > Physics > Chapter 2 - Motion in a Straight Line > A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km/h. Finding the market closed, he instantly turns and walks back home with a speed of 7.5 km/h . What is the (a) magnitude of average velocity, and (b) average speed of the man over the interval of time (i) 0 to 30 min, (ii) 0 to 50 min (iii) 0 to 40 min? [Note: You will appreciate from this exercise why it is better to define average speed as total path length divided by time and not as magnitude of average velocity. You would not like to tell the tired man on his return home that his average speed was zero!]

A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km/h. Finding the market closed, he instantly turns and walks back home with a speed of 7.5 km/h . What is the (a) magnitude of average velocity, and (b) average speed of the man over the interval of time (i) 0 to 30 min, (ii) 0 to 50 min (iii) 0 to 40 min? [Note: You will appreciate from this exercise why it is better to define average speed as total path length divided by time and not as magnitude of average velocity. You would not like to tell the tired man on his return home that his average speed was zero!]

1) is: A force of -F k acts on O A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km/h. Finding the market closed and (b) average speed of the man over the interval of time (i) 0 to 30 min he instantly turns and walks back home with a speed of 7.5 km/h . What is the (a) magnitude of average velocity respectively the origin of the coordinate system. The torque about the point (1 The position-time (x-t) graphs for two children A and B returning from their school O to their homes P and Q