Question

A car travells with a velocity of 72 km/h in 10s , starting from rest .
(a) Find acceleration
(b) average velocity.
(c) distance travelled .

Please solve it.
Most satisfying answer will mark as brainliest.
​

Answer 1

Answer:

(a) Acceleration ( a ) = 2 m / sec²

(b). Average velocity = 10 m / sec

(c) Distance travelled = 100 m

Explanation:

Given :

Initial velocity ( u ) = 0 m / sec

Final velocity ( v ) = 72 km / hr

To convert km / hr into m / sec multiply it by 5 / 18 we get

v = 4 × 5 = 20 m / sec

Time ( t ) = 10 sec

a .

From first equation of motion we have

v = u + a t

put the value here

20 = 0 + a × 10

10 a = 20

a = 2 m / sec² .

b.

Average velocity = u + v / 2

Average velocity = 0 + 20 / 2

Average velocity = 20 / 2 = 10 m / sec

c.

We have second equation of motion

s = u t + 1 / 2 a t²

put the value here

s = 0 + 1 / 2 ×  2 × 10 × 10

s = 10 × 10

s = 100 m

Thus we get all answer.

Answer 2

» A car travells with a velocity of 72 km/h in 10s.

Here ..

• Final velocity (v) = 72 km/hr

=> 72 × $\dfrac{5}{18}$

=> $\dfrac{360}{18}$

=> 20 m/s

• Time (t) = 10 sec

• Initial velocity (u) = 0 m/s (as said in question car travells with a velocity of 72 km/h in 10s, starting from rest. Means it's initial velocity (from starting) is zero)

______________ [ GIVEN ]

• We have to find : a) Acceleration (a)

b) Average velocity

c) Distance travelled (s)

______________________________

a) v = u + at

(From First Law Of Motion)

Put the known values in above formula

=> 20 = 0 + a(10)

=> 20 = 10a

=> 10a = 20

=> a = 2 m/s²

_________ [ ANSWER ]

______________________________

b) Average velocity = $\frac{Final\: velocity\:+\: Initial\: velocity}{2}$

=> $\dfrac{v\:+\:u}{2}$

=> $\dfrac{20\:+\:0}{2}$

=> 10 m/s

__________ [ ANSWER ]

_____________________________

c) s = ut + $\frac{1}{2}$ at²

Put the known values in above formula

=> s = 0(10) + $\frac{1}{2}$ (2)(10)²

=> s = $\frac{1}{2}$ + 200

=>s = $\frac{200}{2}$

=> s = 100 m

____________ [ ANSWER ]

______________________________