Q2 of 53 Page 207

If a car travels 50 m distance in 4s with a acceleration of 5 m/s2, then what was its initial speed?

Using the second equation of motion: s = ut + at2

where: s = distance covered =50 m
u = initial velocity = ?
a = acceleration = 5 m/s2
t = time = 4s


s = ut + at2


50 = u x 4s + x 5 x 42


50 = u x 4s + 40


50 – 40 = u x 4s


10 = u x 4s


u = m/s = 2.5 m/s


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