38. The water drops fall at regular intervals from a tap 5 m above the ground. The third drop is leaving the tap at an instant when the first drop touches the ground. How far above the ground is the second drop at that instant? ( Take g = 10 m/s2 )

38. The water drops fall at regular intervals from a tap 5 m above the ground. The third drop is leaving the tap at an instant when the first drop touches the ground. How far above the ground is the second drop at that instant? ( Take g = 10 \(m/s^2\) )

(a) 1.25 m

(b) 2.50 m

(c) 3.75 m

(d) 5.00 m

Answer :  (c) 3.75 m

\( s = ut + \)\(\frac{1}{2}\)\(at^2 \)

\( 5 = 0 + \)\(\frac{1}{2}\)\((10)(2t)^2 \)

\(\rightarrow t = \)\(\frac{1}{2}\)\(\, s \)

\( s = ut + \)\(\frac{1}{2}\)\(at^2 \)

\( = 0 + \)\(\frac{1}{2}\)\((10)\)\(\left(\frac{1}{2}\right)^2\)

\( = \)\(\frac{5}{4}\)\( = 1.25\, m \; (\text{from tap}) \)

x = 5 - 1.25 = 3.75 m