Question

A car acquired a velocity of 72km/h in 10 seconds starting from rest. Fimd tha average velocity

Answer 1

Initial Velocity = u = 0

Final velocity = v = 72 km/hr = 72 x 5/18 = 20 m/s

Time = t = 10 sec

Acceleration = a

Equation of motion :-

v = u + at
20 = 0 + 10a

a = 20/10

a = 2 m/s²

displacement = distance traveled = s

Equation of motion :-
v² - u² = 2as

20² = 2 × 2 × s

400 = 4s

s = 400/4

s = 100 m

Average velocity = displacement / time

= 100 / 10
= 10 m/s