Question

please answer these​

Answer 1

Answer:

1. a. 16 m
2. b. 16 m
3. a. 4 m/s
4. b. 7 m

Explanation:

given,

body starts from rest ⇒ initial velocity (u) = 0

acceleration (a) = 4m/s²

1) given, time (t) = 4 s

   displacement (s) = ?

   from s = ut + at²/2

   s = (0)4 + 2(4²)/2

   s = 16 m

2) since, the question was not provided with the direction of particle,

   it is to be assumed that particle travels in the same direction throughout   the journey

   in such case, distance = displacement

   from above solution, distance travelled = 16 m

3) given, time (t) = 2 s

   velocity (v) = ?

   from  a = (v - u)/t

   v = u + at

      = 0 + 2(2)

   v = 4 m/s

4) nth second = 4th second

   displacement at nth second (Sₙ) = ?

   Sₙ = u + a(2n - 1)/2

       = 0 + 2[2(4) - 1]/2

       = 8 - 1

   Sₙ = 7 m