Question

With an initial velocity of 20 km/h, a car accelerated at 8 m/s2 for 10 seconds.
a) What is the position of the car at the end of the 10 seconds?

Answer 1

We have been given that initial velocity of car is 20 km/h accelerating at 8 m/s² for 10 seconds.

We have to find position of car at the end of 10 seconds.

Solution

Here, initial velocity of car = 20 km/h

⇒ Initial velocity = 20 × (5/18) m/s

⇒ Initial velocity (u) = 5.56 m/s

Acceleration of car (a) = 8 m/s²

Time taken by car (t) = 10 seconds.

Using 2nd equation of motion :

⇒ s = ut + ½ at²

⇒ s = (5.56 × 10) + ½ (8 × 10²)

⇒ s = 55.6 + (4 × 100)

⇒ s = 55.6 + 400

⇒ s = 455.6 m

Therefore,

Position of car after 10 seconds is 455.6 m away from the initial position.

Answer 2

Answer:

Given information –

• Initial velocity = u = 20 km/hr = 20 * 5/18 = 5.56 m/s.
• Acceleration = a = 8 m/s²
• Time period = 10 sec.

To Find –

• The position of the car after 10 seconds.

Solution –

We will have to use the second equation of motion for finding the the position of the car after 10 seconds.

s = ut + ½ at²

➸ s = 5.56*10 + ½*8*(10)²

➸ s = 55.6 + 4*100

➸ s = 55.6 + 400

➸ s = 455.6 m

Hence, the total displacement or the change in position of the car is 455.6 metres away from the initial position.