Worksheet on Expressing Speed in Different Units is provided here. Students can check different problems on converting the units of speed from one to another and how to find the speed if the distance and time are given. Students who are preparing for the exams have to go through this Expressing Speed in Different Units Worksheet for a better understanding of the concept.

Get the solved example questions on the unit conversion of speed from the following sections. Generally, speed is expressed as the division of distance covered by the object to the time taken to cover the distance. Use the speed formula and convert its unit easily.

**Also, Read**

## Converting Units of Speed Examples

**Example 1:**

Calculate the speed in the following cases.

(i) Distance = 2000 m, time = 20 sec

(ii) Distance = 150 km, time = 3 hours

(iii) Distance = 600 m, time = 12 sec

**Solution:**

The speed formula is

Speed = \(\frac { Distance }{ Time } \)

(i) Given that,Distance = 2000 m, time = 20 sec

Speed = \(\frac { Distance }{ Time } \)

= \(\frac { 2000 m }{ 20 sec } \)

= 100 m/sec

The speed is 100 m/s.

(ii)Given that,

Distance = 150 km, time = 3 hours

Speed = \(\frac { Distance }{ Time } \)

= \(\frac { 150 km }{ 3 hours } \)

= 50 km/hr

The speed is 50 km/hr.

(iii) Given that,

Distance = 600 m, time = 12 sec

Speed = \(\frac { Distance }{ Time } \)

= \(\frac { 600 m }{ 12 sec } \)

= 50 m/sec

The speed is 50 m/s.

**Example 2:**

David runs 100 m in 10 seconds. Find his speed and express in km/hr.

**Solution:**

Given that,

Distance covered by David = 100 m

time taken = 10 seconds

Speed = \(\frac { Distance }{ Time } \)

= \(\frac { 100 }{ 10 } \)

Speed = 10 m/sec

We know 1 km = 1000m and 1 hour = 60 minutes and in turn 1 minute = 60 sec

On simplifying we have m/sec = \(\frac { 18 }{ 5 } \) km/hr

To convert speed in m/s to km/hr multiply the speed by \(\frac { 18 }{ 5 } \)

So, speed = 10 x \(\frac { 18 }{ 5 } \)

= \(\frac { 180 }{ 5 } \)

= 36 km/hr

Therefore, speed is 36 km/hr

**Example 3:**

Express each of the following speeds in kilometres per hour.

(i) 42 m/sec

(ii) 89 m/min

(iii) 69 m/sec

**Solution:**

(i) Given speed is 42 m/sec

To convert 42 m/sec to km/hr multiply it by \(\frac { 18 }{ 5 } \)

Speed = 42 m/sec x \(\frac { 18 }{ 5 } \)

= \(\frac { 42 x 18 }{ 5 } \)

= \(\frac { 756 }{ 5 } \)

= 151.2

So, the speed is 151.2 km/hr

(ii)Given speed is 89 m/min

Speed = 89 m/min x \(\frac { 1/1000 }{ 1/60 } \)

= \(\frac { 89 x 60 }{ 1000 } \)

= \(\frac {5340 }{ 1000 } \)

= 5.34

So, the speed is 5.34 km/hr

(iii)Given speed is 69 m/sec

To convert 69 m/sec to km/hr multiply it by \(\frac { 18 }{ 5 } \)

Speed = 69 m/sec x \(\frac { 18 }{ 5 } \)

= \(\frac { 69 x 18 }{ 5 } \)

= \(\frac { 1242 }{ 5 } \)

= 248.4

So, the speed is 248.4 km/hr

**Example 4:**

Express each of the following speeds in meters per second.

(i) 25 km/hr

(ii) 72 km/hr

(iii) 5 km/minute

**Solution:**

(i) Given speed is 25 km/hr

To express the speed in the form of km/hr as m/sec multiply the given speed by \(\frac { 5 }{ 18 } \)

Speed = 25 km/hr x \(\frac { 5 }{ 18 } \)

= \(\frac { 25 x 5 }{ 18 } \)

= \(\frac { 125 }{ 18 } \)

= 6.94 m/sec

Therefore, speed is 6.94 m/sec

(ii) Given speed is 72 km/hr

We know that 1 km = 1000 m, 1 hr = 3600 sec

Speed = 72 x \(\frac { 1000 m }{ 3600 sec } \)

= \(\frac { 72 x 1000 }{ 3600 } \)

= \(\frac { 72000 }{ 3600 } \)

= 20 m/sec

Therefore, speed is 20 m/sec.

(iii) Given speed is 5 km/minute

We know that 1 km = 1000 m, 1 hr = 60 minutes

Speed = 5 x \(\frac { 1000 m }{ 60 min} \)

= \(\frac { 5 x 1000 m }{ 60 min } \)

= \(\frac { 5000 }{ 60 } \)

= 83.3

Therefore, speed is 83.3 m/minute

**Example 5:**

A train covers a distance of 2100 km in 15 hours, find its speed in m/min and m/sec.

**Solution:**

The distance covered by the train = 2100 km

The time taken = 15 hours

Speed of the train = \(\frac { Distance }{ Time } \)

= \(\frac { 2100 km }{ 15 hr } \)

= 140 km/hr

The speed in m/min = 140 x \(\frac { 1000 }{ 60 } \)

= \(\frac { 140 x 1000 }{ 60 } \)

= \(\frac { 140000 }{ 60 } \)

= 2333.3

The speed in m/sec = 140 x \(\frac { 1000 }{ 3600 } \)

= \(\frac { 140 x 1000 }{ 3600 } \)

= \(\frac { 140000 }{ 3600 } \)

= 388.88

So, the train speed is 2333.3 meters per minute or 388.88 meters per second.

**Example 6:**

Two persons went to the park in their cars. If person A covers a distance of 15 km in 12 minutes and person B covers a distance of 4000 m in 3 minutes. If they start at the same time, who reaches the park first.

**Solution:**

The speed of person A = \(\frac { Distance }{ Time } \)

= \(\frac { 15 }{ 12} \) km/min

The speed of person B = \(\frac { 4000 }{ 3 } \) m/min

Express the speeds in m/sec

Person A speed = \(\frac { 15 }{ 12} \) x latex]\frac { 1000 }{ 60} [/latex]

= latex]\frac { 15 x 1000}{ 12 x 60} [/latex]

= latex]\frac { 15000 }{ 720} [/latex]

= 20.83 m/sec

Person B speed = \(\frac { 4000 }{ 3 } \) x latex]\frac { 1 }{ 60} [/latex]

= \(\frac { 4000 x 1}{ 3 x 60 } \)

= \(\frac { 4000 }{ 180 } \)

= 22.2 m/sec

By observing those speeds, person B reaches the park first.