Lamp-posts are placed 30 metres apart along a road. How long wili a ca

1.	Lamp-posts are placed 30 metres apart along a road. How long wili a car travelling at 45 km ahour take to pass 6 lamp-posts, not counting the first of them?Il.
Answer» Since we are working with metres, we convert the speed into m/s We do this by multiplying the speed in km/h by 5/18 45×5/18=25/2 This gives :12.5m/s The distance covered excluding the first post we have :5×30=150m For us to get the time taken we use the formulae : Time=Distance/Speed 150m/12.5m/s=12 The time taken is 12 seconds.

Lamp-posts are placed 30 metres apart along a road. How long wili a car travelling at 45 km ahour take to pass 6 lamp-posts, not counting the first of them?Il.

Answer»

Since we are working with metres, we convert the speed into m/s

We do this by multiplying the speed in km/h by 5/18

45×5/18=25/2

This gives :12.5m/s

The distance covered excluding the first post we have :5×30=150m

For us to get the time taken we use the formulae : Time=Distance/Speed

150m/12.5m/s=12

The time taken is 12 seconds.