Question

a car accelerates uniformly from 18 kilometre per hour to 36 km per hour within a distance of 15 metre the uniform acceleration of the car is

Answer 1

Answer

• Uniform acceleration of the car = 2.5 m/s²

Given

• A car accelerates uniformly from 18 kilometre per hour to 36 km per hour within a distance of 15 metre

To Find

• Acceleration of the car , a = ? m/s²

Concept Used

Equations of motion

• v = u + at
• s = ut + ¹/₂ at²
• v² - u² = 2as

Solution

Initial velocity , u = 18 km/h = 18 × ⁵/₁₈ m/s = 5 m/s

⇒ u = 5 m/s

Final velocity , v = 36 km/h = 36 × ⁵/₁₈ m/s = 10 m/s

⇒ v = 10 m/s

Distance , s = 15 m

Acceleration , a = ? m/s²

Now , Apply 3 rd equation of motion .

⇒ v² - u² = 2as

⇒ 10² - 5² = 2a(15)

⇒ 100 - 25 = 30a

⇒ 75 = 30a

⇒ 30a = 75

⇒ a = 2.5 m/s²