Posted by aisha on Monday, March 5, 2012 at 3:53pm.
A ball starts from rest and rolls down a hill with uniform acceleration, traveling 170 m during the second 5.5 s of its motion.
How far did it roll during the first 5.5 s of motion?
Express your answer using two significant figures.
x= m

physics  drwls, Monday, March 5, 2012 at 6:12pm
Speed at middle of second 5.5 s interval = 3 x (Speed at middle of first 5.5 s interval) = 170/5.5 = 30.91 m/s
= (average speed during that interval)
Speed at 8.25 s = 3 x speed at 2.75 s.
Therefore:
speed at 2.75 s = (1/3)*30.91 = 10.30 m/s
Distance travelled during first interval 10.30 x 5.5 = 56.65 m
Rounding that two 2 significant figures gives 57 m. 
maths  Anonymous, Friday, May 11, 2012 at 7:34am
plzzz explain how to draw root 5 on a number line