A car accelerates uniformly from 18 Kmh-1 to 36 Kmh-1 in 5s. calculate the acceleration and the acceleration and distance
covered by the car in that time
Answers
Given :
Initial velocity = 18km/hr
Final velocity = 36km/hr
Time interval = 5s
To Find :
Acceleration of car and distance covered.
Solution :
❖ Acceleration is defined as the rate of change of velocity
- It is a vector quantity having both magnitude as well as direction.
- It can be positive, negative or zero.
- SI unit : m/s²
- Dimension formula : [L¹T‾²]
Formula : a = (v - u) / t
» u = 18 km/hr = 5 m/s
» v = 36 km/hr = 10 m/s
By substituting the given values;
➙ a = (10 - 5) / 5
➙ a = 5/5
➙ a = 1 m/s²
❒ Distance travelled by car :
Applying 3rd equation of kinematics;
➠ v² - u² = 2as
➠ 10² - 5² = 2(1)s
➠ 100 - 25 = 2s
➠ 2s = 75
➠ s = 75/2
➠ s = 37.5 m
Initial velocity = 18km/hr
Final velocity = 36km/hr
Time interval = 5s
Acceleration of car and distance
Acceleration:
SI unit : m/s²
Dimension formula : [L¹T‾²]
Formula : a = (v - u) / t
u = 18 km/hr = 5 m/s
v = 36 km/hr = 10 m/s
Substituting the given values;
➙ a = (10 - 5) / 5
➙ a = 5/5
➙ a = 1 m/s²
Distance :
As per 3rd equation of kinematics;
v² - u² = 2as
10² - 5² = 2(1)s
100 - 25 = 2s
2s = 75
s = 75/2
s = 37.5 m