Which one of the following equation represents the motion of a body moving with constant finite acceleration? In these equation, y denotes the displacement in time t and p, q and r are constant:
(a) y = (p + qt )(t + pt)
(b) y = p + t/r
(c) y = (p + t) (q + t ) (r + t)
(d) y =
Answers
answer : option (A)
explanation : acceleration is the rate of change of velocity and velocity is the rate of change of displacement.
means, to find acceleration, differentiate displacement function two times.
i.e., a = d²y/dt²
let's check options.
option (A) : y = (p + qt)(t + pt)
differentiating both sides,
dy/dt = q(t + pt) + (p + qt)(1 + p)
again differentiating both sides,
d²y/dt² = q(1 + p) + q(1 + p) => finite and constant terms
so, option (A) is correct.
option (B) : y = p + t/r
differentiating both sides,
dy/dt = 0 + 1/r
again differentiating both sides,
d²y/dt² = 0 => acceleration is zero
it is incorrect.
option (C) : y = (p + t)(q + t)(r + t) [ it is a cubic polynomial and after twice differentiation, we get d²y/dt² depends on t so, acceleration will be variable. ]
it is also incorrect.
option (D) : y = (p + qt)/(rt) [ it can't be constant because variable term, t is placed at denominator. hence, acceleration will be variable ]
so, it is also incorrect.
hope it helps u dude ❤❤❤❤❤