Question

An object travels 10 km at a speed of 100 m/s and
another 10 km at 50 m/s. The average speed over
the whole distance is :-
(1) 75 m/s
(2) 55 m/s
(3) 66.7 m/s
(4) 33.3 m/s​

Answer 1

Answer:

total distance covered =10×1000+10×1000 m=20×1000m

or 20,000m

total time taken by the object =10×1000m/100( distance /time)+10×1000/50

=100+200 sec

=300 sec

so avg speed = total distance/total time

=20000/300

=200/3 m/sec

=66.7m/s