Question

Define speed. A car covers a distance of 20 km in 20 minutes. What is it's speed. ( please show in detail) ​

Answer 1

Answer:

Step-by-step explanation:

Speed is the distance travelled per unit time .

Speed = Distance/Time

•Speed is scalar quantity

V = D/T

Units of speed are :-

SI unit: m/s, m s−1

Dimension: L T^-1

Given,

A car covers the distance of 20km in 20 minutes

We have ,

Distance travelled (d) = 20km

Time taken to travel(t) = 20 minutes ,20/60 = 1/3

According to formula,

Speed = distance/time

V = d/t

V = 20/20

V = 1km/hr

So,the speed of the car is 60 kilometre(km)/per hour (hr)

Speed = 1 km/hour => 60kmhr {1 hr=60min}

Answer 2

$\huge\underline\mathfrak\blue{Speed}$

» It is the distance covered by an object in per unit time.

» Its S.I unit is meter per second (m/s).

» It is a scaler quantity.

» It can never be zero.

» Mathematical formula :

$speed = \frac{distance}{time}$

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Now, lets come to the numerical.

Given : Distance = 20 km and time = 20 minutes.

To find : speed of car

Solution : We know that, the S.I unit of speed is meter per second.

So, we have to convert the distance in meters and time in seconds.

Therefore, distance = 20 km

1 km = 1000 m

Multiply 20 km by 1000

we get, 20000 meters.

Now, Time = 20 minutes ( Given )

1 minute = 60 seconds

Multiply 20 minutes by 60.

We get, 1200 seconds.

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Also,

$speed = \frac{distance}{time}$

$speed = \frac{20000}{1200}$

$speed = \frac{200}{12 } \\ speed = \frac{50}{3} \\ speed = 16.67 \: {ms}^{ - 1}$

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Hence, speed of car is 16.67 ms-¹.