A security camera, taking pictures each half a second, films a
cyclist going by. In the film, the cyclist appears to go forward
while the wheels appear to go backwards. Why?
How far have these students walked by the time the teacher's car
reaches them after their bus broke down?
A train leaves on time. After it has gone 8 miles (at 33mph) the
driver looks at his watch and sees that the hour hand is exactly
over the minute hand. When did the train leave the station?
The problem can be solved by considering the relative speed of
The speed of approach of the trains is 125 km/h on a 100 km
track, so they will collide after a time 100/125 = 4/5 hour. Sidney
flies at 100 km/h for 4/5 hour so he flies 80 km.
Finally, if Sidney were to fly exactly 100 km, the relative
speed of the trains would be 100 km/h, provided Sidney was
continuing to fly at 100 km/h. OR .....
there is another way - do you have any suggestions?
We received the correct solutions
Smith(South Greenhoe Middle