mathematics

class VII

#### Key Concepts

speed, distance, time taken

#### essential questions

How is time and distance used to calculate speed ?
How do we find a relationship between time, distance and speed?

#### Remembering:

Speed

1. Find speed when, distance is 142 km and time is 2 hours.
2.  The speed of the train is 72 km per hour. Find its speed in metre per second.
3.  Express the speed of 60 m per minute in km per hour.
4. Find the speed in the following cases:  (i) Distance = 90 km, Time = 2 hours    (ii) Distance = 36000 m, Time = 24 seconds    (iii) Distance = 750 km, Time = 15 hours.
5. Express each of the following speeds in meters per second:  (i) 36 km per hour   (ii) 72 km per hour
6. Express each of the following speeds in km per hour:  (i) 900 m per minute  (ii) 45 m per second

#### understanding:

1. Find out the distance covered when, speed is 960 km/hour and time is 1 hour 50 minutes.
2. Determine the time taken when, distance is 7150 km and speed is 780 km/hr.
3. If distance travelled by a train is 495 km in 4 hours 30 minutes, what is its speed?
4. A fox ran 1000 m in 5 minutes. Find its speed.
1. A man can cover 17 ½ km in 5 hours. Find his speed in

(i) m/min

(ii) m/sec

5. If the distance covered by a train is 360 km in 4 hours, find its speed.

#### Application:

1. A cyclist covers 950 m in 5 minutes. Find his speed in km/ hour.
2. A man runs at the speed of 10 km/hr. How much time will he take to cover 750 metres?
3. Aaron ran 500 metre in 100 Seconds. Find the speed in km per hour.
4. A cyclist travels at a speed of 20 km/hour. How far will he travels in 50 minutes?
5. A student has to reach his school in 15 minutes. If the school is 800 metres way, at what speed should he walk?