Question

The position of an object moving along x-axis is given by x = a + bt2
where a = 8.5 m, b = 2.5 m s–2 and t is measured in seconds. Its velocity at t = 0 s will be
a. 0 m/s
b. 2 m/s
c. 4 m/s
d. 6 m/s

Answer 1

Answer:

Correct option is

C

15 m s−1

Position is given as   x=a+bt2=8.5+2.5t2

Position at t=2 s,  x2=8.5+2.5(2)2=18.5 m

Position at t=4 s,   x1=8.5+2.5(4)2=48.5 m

Displacement  S=x2−x1=48.5−18.5=30 m

Time taken  t=4−2=2 s

Average velocity  Vavg=tS=230=15 m/s

Answer 2

Answer:

THE CORRECT ANSWER IS C

Explanation:

THE ANSWER IS GIVEN ABOVE IN IMAGE