Question

Q11. A car starts from rest and picks up a velocity of 18 m/s in 20 seconds. Calculate the acceleration of the car​

Answer 1

Explanation:

A car starts from rest and picks up a velocity of 20 m/s in 10 seconds. Calculate the acceleration of the car. - 448181.

Top answer · 27 votes

As car starts from rest u=0 v=20m/s, t=10m/s by the first equation of motion v=u+at, 20m/s=0+a10s, hence by solving above we get a =2m/s square More

Answer 2

$\bf\large\red{\underline{given : }}$

Car starts from rest , u = 0m/sec

Final velocity , v= 18m/sec

Time taken , t = 20sec

$\bf\large\red{\underline{to \: find : }}$

Acceleration , a = ?

$\bf\large\red{\underline{ solution : }}$

◆By 1st Kinematical equation,

☞v = u + at

Here ,

v = final velocity

u = initial velocity

a = acceleration

t = time taken

⇝Putting values in equation,

↬18 = 0 + a(20)

↬18 = 20a

↬ a = 18/20

↬ a = 0.9m/sec²

$\bf\large\red{\underline{answer : }}$

Acceleration , a = 0.9m/sec²

$\bf\large\red{\underline{additional \: informtion : }}$

◆ 2nd Kinematical equation,

➜ s = ut + (1/2)at²

◆ 3rd Kinematical equation,

➜ v² = u² + 2as

Here ,

s = displacement

u = initial velocity

v = final velocity

a = acceleration

t = time taken

Note :

• These Kinematical equations are only valid when acceleration is constant.