Question

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 1. 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) o to
50 min, (iii) o 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 !​

Answer 1

Answer:

since displacement is zero

average velocity is also zero

for Average speed

formula is 2uv by/ u+v

= 2×5×7.5÷5+7.5

=6