Question

at a given instant, the speed of a
scooter is 54 km/he and after 10 sec it
becomes 18 km/hr calculate it acceleration,
assuming to
be constant calculate the
distance in which it will comes to rest​

Answer 1

Answer:

10 m is your answer for your question

Answer 2

Answer:

$\bigstar{\bold{Acceleration=\:-1\:m/s^{2} }}$

$\bigstar{\bold{Distance=112.5\:m}}$

Explanation:

$\Large{\underline{\underline{\bf{Given:}}}}$

• Initial speed (u) = 54 km/hr = 15 m/s
• Final speed(v)  = 18 km/hr = 5 m/s
• Time taken (t) = 10 s

$\Large{\underline{\underline{\bf{To\:Find:}}}}$

• Acceleration(a)
• Distance (s)

$\Large{\underline{\underline{\bf{Solution:}}}}$

Acceleration:

→ Acceleration is given by the equation

 a = (v - u) /t

→ Substituting the given datas ,we get,

  a = 5 - 15/10

  a = -10/10 = -1 m/s²

$\boxed{\bold{Acceleration=\:-1\:m/s^{2} }}$

Here acceleration is negative since it is retardation or deceleration.

Distance travelled when it comes to rest:

→ By the third equation of motion,

  v² - u² = 2as

→ Here final velocity will be 0, v = 0

  0 - 15² = 2 × - 1 × s

  s = 225/2

  s = 112.5 m

$\boxed{\bold{Distance=112.5\:m}}$

$\Large{\underline{\underline{\bf{Notes:}}}}$

→ The 3 equations of motion are:

• v = u + at
• s = ut + 1/2 × a × t²
• v² - u² = 2as