Question

the velocity of a car increases from 30km/hr to 45km/hr in 5 min . assuming the acceleration to be uniform calculate the distance travelled​

Answer 1

Distance Travelled = 3.125 km

Explation:

See in the attachment.

Answer 2

Given :

Initial velocity of the car = 30 km/hr

Final velocity of the car = 45 km/hr

Time taken = 5 min

To find :

The acceleration and distance covered by the car.

Solution :

Firstly we have to convert km/hr to m/s

1 km/hr = 5/18 m/s

30 km/hr = 30 × 5/18 = 25/3 = 8.3 m/s

45 km/hr = 45 × 5/18 = 25/2 = 12.5m/s

As we are provided with initial velocity, final velocity and time we can use first equation of motion .i.e.,

v = u + at

here,

• v denotes final velocity
• u denotes initial velocity
• a denotes acceleration
• t denotes time

substituting all the given values in the equation,

➠ v = u + at

➠ 12.5 = 8.3 + (a)(300)

➠ 12.5 - 8.3 = 300a

➠ 4.2 = 300a

➠ a = 4.2 /300

➠ a = 0.014 m/s²

thus the acceleration of the car is 0.013 m/s².

Now, to find distance covered by the car we can use second equation of motion .i.e.,

s = ut + 1/2at²

here,

• s denotes distance covered.
• u denotes initial velocity.
• t denotes time.
• a denotes acceleration.

by substituting all the given values in the formula,

➠ s = ut + 1/2at²

➠ s = (8.3)(300) + 1/2(0.014)(300)²

➠ s = 2490 + 630

➠ s = 3120m$.$

thus the distance covered by the car is 3120 m