On January 1st, Jerome concocts a rumor and tells Beth. On January 2nd, they each tell a new person. By the end of January 2nd, four people have heard the rumor. On each subsequent day, each person who has heard the rumor spreads it to a new person. How many people have heard the rumor by the end of January 8th?
Answers
Answer:
answer :512
Step-by-step explanation:
for each day the number doubles. 1st day is 2
and 2nd day is 4 ,and 3rd day is 8 and soon till January 8
Answer:
Let the initial velocity of the body be u m/s; and the constsnt acceleration be a m/s². Then displacemet (distance covered) of the body after t second is given by
s = u t + ½ a t² ———————————-(1)
The body covers 20 m in 2s and 80 m in 4 s.
20 = u×2 + ½ a 2²; => 20 = 2 u + 2 a
u + a = 10 —————————————(2)
80 = u×4 + ½ a 4²; => 80 = 4 u + 8 a; this gives,
u + 2 a = 20 ——————————————(3)
Solving (2) and (3) for u and a we get
u = 0 m/s and a = 10 m/s² ————————(4)
To obtain the distance covered in the next 4s we need to find the velocity at the beginning of this interval using,
v = u + a t => v = 0 m/s + 1.....