AP EAMCET2014PhysicsMotion in One Dimension
A person walks along a straight road from his house to a market 2.5 ~km away with a speed of 5 ~km / h and instantly turns back and reaches his house with a speed of 7.5 ~km / h . The average speed of the person during the time interval 0 to 50 ~min is ( in m / s )
Options
- A4 2 3
- B5 3
- C5 6
- D1 3
Correct answer
B. 5 3
Step-by-step solution
A according to question, t₁= 2.5 5 = 1 2 ~h =30 ~min and t₂= 2.5 7.5 = 1 3 ~h =20 ~min So, the average speed aligned & = Total distance ( in metre ) Total time ( in second ) & = (2.5+2.5) 1000 (30+20) 60 & = 5 1000 50 60 = 50 30 = 5 3 ~m / s aligned