Question

A body covers 26, 28, 30, 32 meters in $10^{th}$, $11^{th}$, $12^{th}$ and $13^{th}$ seconds respectively. The body starts

• A. from rest and moves with uniform velocity
• B. from rest and moves with uniform acceleration
• C. with an initial velocity and moves with uniform acceleration
• D. with an initial velocity and moves with uniform velocity

Answer 1

Answer: (C)

The distance covered in nth second is $S_n = u + \frac{1}{2} (2n - 1)a $
where u is initial velocity & a is acceleration then $26 = u + \frac{19a}{2}$ .....(1)
$28 = u + \frac{21a}{2} $ ....(2)
$30 = u + \frac{23 a}{2}$ .....(3)
$32 = u + \frac{25a}{2}$ ......(4)
From eq. (1) & (2) we get u = $7 m/ \sec, a = 2 \, m/ \sec^2$
$\therefore $ The body starts with initial velocity u = 7 m/sec
and moves with uniform acceleration $a = 2 m/ \sec^2$