Question

ce A train starting from rest attains a velocity of 72
km/hr in 5 minutes - Assuming that the acceleration
en wriform, find in the acceleration and ii) the distance traveled by the train While it attained this velocity​

Answer 1

Answer:

Given:

Initial Velocity = 0 km/hr

Final velocity = 72 km/hr

Time taken = 5 minutes

To find:

• Acceleration of train
• Distance travelled

Calculation:

We need to convert km/hr to m/s first .

72 km/hr = 72 × (5/18) = 20 m/s

$acc. = \dfrac{20 - 0}{(5 \times 60)} = \dfrac{20}{300} = \dfrac{1}{15} \: m {s}^{ - 1}$

Distance travelled be d :

${v}^{2} = {u}^{2} + 2ad$

$= > {(20)}^{2} = {0}^{2} + 2(\dfrac{1}{15})(d)$

$= > d = \dfrac{400 \times 2}{15}$

$= > d = 3000\: m$

$= > d = 3 \: km$

So final answer is :

Distance travelled is 3 km

Answer 2

Answer:

Given:

⇏ A train starting from rest attains a velocity of 72 km/hr in 5 minutes.

Find:

⇏ Find the acceleration and the distance traveled by the train.

Know term's:

⇏ Initial velocity = (v)

⇏ Final velocity = (u)

⇏ Distance = (D)

⇏ Acceleration = (A)

⇏ Kilometre/Hour = (km/hr)

⇏ Minute/Second = (m/s)

Note:

.•. ATQ, let's covert the given km/hr in to m/s.

72 km/hr.

.•. (72 × 5/18)

⇏ 20 m/s

Using the above values for further calculations:

⇏ A = (20 - 0)/(5 × 6) = 20/300

⇏ 1.15 m/s-¹

Using formula:

⇏ v² = u² + 2ad

⇏ (20)² = 0² + 2 (1/15)

⇏ D = (400 × 2)/15

⇏ D = 3000 m

Note:

⇏ 1 km = 1000 m

.•. 3000 m = 3 km

⇏ D = 3 km

Therefore, 3 km is the distance travelled.