Obtain a relation for the distance travelled by an object moving with a uniform acceleration in the interval between 4th and 5th second.
Using the second equation of motion: s = ut + 
at2
where: s = distance covered
u = initial velocity
a = acceleration
t = time = 4s
Distance covered in 4s :
s1 = ut + 
at2
s1 = u × 4 + 
a × 42
s1 = 4u + 
a ………………… equation 1
Distance covered in 5s:
s2 = ut + 
at2
s2 = u × 5 + 
a × 52
s2 = 5u + 
a …………………… equation 2
Distance travelled by an object between 4th and 5th sec:
equation 2 – equation 1
(s2 – s1 ) = (5u + 
a ) - (4u + 
a)
(s2 – s1 ) = 5u – 4u +
a - 
a)
(s2 – s1 ) = u + 
a
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