JAMB - Physics (1993 - No. 17)
Radio waves emitted from an antenna are picked up by a radar after reflection from an aircraft in 4 x 10-3S. How far is the aircraft from the antenna? [c = 3 x 108ms-1 ]
6.0 x 102ms-1
1.2 x 103km
3.0 x 103km
6.0 x 10 5km
Penjelasan
Time = 1 x 4 x 10-3sec
distance = velocity x time
= 3 x 108 x 4 x 10-3
= 6 x 105m
distance = velocity x time
= 3 x 108 x 4 x 10-3
= 6 x 105m