Question

Derive equation: a] v = u + at²
b] s =ut + 1/2 at²
c] v² - u² = 2as by graphik method​

Answer 1

Answer:

v = u + at

s = u + 1/2 at²

v² = u² + 2as

solution : let a particle moves with initial velocity u after time t, its velocity becomes v due to acceleration acting on particle is a.

see figure,

slope of velocity - time graph = acceleration

⇒(v - u)/(t - 0) = a

⇒v - u = at

⇒v = u + at .........(1)

area enclosed the velocity - time graph = displacement covered by particle

⇒area of trapezium formed as shown in figure = S

⇒S = 1/2 [v + u ] × t

from equation (1),

⇒S = 1/2 [u + at + u ] × t

⇒S = 1/2 [2u + at] × t

⇒S = ut + 1/2 at² ...........(2)

we know, acceleration, a = v dv/ds

⇒a ∫ds = ∫v dv

⇒a[s] = [v²/2]

⇒as = 1/2 [v² - u²]

⇒2as = v² - u²

⇒v² = u² + 2aS ............(3)

Step-by-step explanation: