Question

find the total distance travelled by the car if it starts from rest and moves with a speed of 45 km/hr for 30 minutes​

Answer 1

Given data :-

• Car start from rest and moves with a speed of 45 km/hr for 30 minutes.

Solution :-

Here,

→ u = initial velocity

→ v = final velocity

→ a = acceleration

→ t = time

→ s = distancement of object

Now, {according to given}

→ u = 0

→ v = 45 km/hr

→ t = 30 min

We need to convert velocity in m/s.

→ v = 45 km/hr = {[45×1000}/{60×60]}m/s

→ v = 45 km/hr = {45000/3600}m/s

→ v = 45 km/hr = {25/2}m/s

→ v = 45 km/hr = 12.5 m/s

We need to convert time in sec

→ t = 30 min = {30×60}sec = 1800 sec

Now,

→ a = [v - u]/t

→ a = [12.5 - 0]/1800

→ a = 12.5/1800

→ a = 1/144 m/s²

Now, by formula :-

→ v² = u² + 2as

→ v² - u² = 2as

→ (12.5)² - 0 = 2 × 1/144 × s

→ 156.25 = 1/72 × s

→ s = 156.25 × 72

→ s = 11250 m

Hence,distance travel by car is 11250 m.