Question

A car moving with uniform acceleration attains speed of 36km/hr in 2 minutes find the acceleration ​

Answer 1

✬ Acceleration = 0.083 m/s² ✬

Explanation:

Given:

• Initial velocity of car is 0.
• Final velocity of car is 36 km/h.
• Time taken to attain final speed is 2 minutes.

To Find:

• What is the acceleration of car ?

Formula to be used:

• v = u + at

Solution: First change the final velocity from km/h to m/s and also time to seconds.

[ To change km/h to m/s multiply by 5/18 ]

➙ Final velocity = 36(5/18) = 10 m/s.

[ 1 minutes = 60 seconds ]

➙ 2 minutes = 2(60) = 120 seconds.

Now, we have

• v = 10 m/s.
• u = 0 m/s.
• t = 120 s.

$\implies{\rm }$ v = u + at

$\implies{\rm }$ 10 = 0 + a(120)

$\implies{\rm }$ 10 = 120a

$\implies{\rm }$ 10/120 = a

$\implies{\rm }$ 0.083 m/s² = a

Hence, the acceleration of car is 0.083 m/s².

__________________

➟ The rate of change of velocity is called acceleration. It is denoted by a.

➟ The velocity at which motion starts is termed as initial velocity. It is denote by u.

➟ The last velocity of an object after a period of time. It is denoted by v.

Answer 2

Given :-

• Initial velocity of car = 0.
• Final velocity of car = 36 km/h.
• Time taken to attain final speed = 2 minutes.

To Find :-

• Acceleration of car

Formula :-

• v = u + at

Where,

• v = Final Velocity
• u = Initial Velocity
• a = Acceleration
• t = Time taken

Solution :-

First of all we change the final velocity from km/h to m/s and also time to seconds.

→ Final velocity = 36(5/18) = 10 m/s.

[ We know { 1 minute = 60 seconds } ]

→ 2 minutes = 2(60) = 120 seconds.

Now, we have

• v = 10 m/s.
• u = 0 m/s.
• t = 120 s.

Put the values,

10 = 0 + a(120)

=> 10 = 120a

=> - 120a = - 10

=> a = - 10/- 120

=> a = 0.083 m/s²

Hence, the acceleration of car is 0.083 m/s².