Question

a car starting from rest and moving with uniform acceleration attains a speed of 60km/h in 20 minutes.find the acceleration in km/h​

Answer 1

Answer:

2 km

Explanation:

Initial Velocity = 0 km/ h

Final Velocity = 60 km/ h

Time = 0.3 h

a = v - u/t

a = 60 km/ h - 0 km/h

0.3 h

a = 2 km

please tell me if the answer is right or wrong

Answer 2

Explanation:

Given

A car starting from rest and moving with uniform acceleration attains a speed of 60 km/h in 20 minutes

To Find

Acceleration (km/h²)

Solution

We know that

Equation of motion

\sf \longrightarrow v=u+at⟶v=u+at

Here

u = Initial velocity

v = Final velocity

a = Acceleration

t = Time

According to the question

We are asked to find acceleration

Hence

We must find "a"

Therefore

\sf \longrightarrow a=\dfrac{v-u}{t}⟶a=

t

v−u

Given that

A car starting from rest and moving with uniform acceleration attains a speed of 60 km/h in 20 minutes

Hence

u = 0 [starts from rest]

v = 60 km/h

t = 20 min = 0.333 hour

Substituting the values

We get

\sf \longrightarrow a=\dfrac{60-0}{0.333} \ km/h^{2}⟶a=

0.333

60−0

km/h

2

\sf \longrightarrow a=\dfrac{60}{0.333} \ km/h^{2}⟶a=

0.333

60

km/h

2

\sf \longrightarrow a=180.18 \ km/h^{2}⟶a=180.18 km/h

2

Therefore

\sf \longrightarrow a \approx 180 \ km/h^{2}⟶a≈180 km/h

2