1) The speed of a moving object relative to an observer in another moving object is called .....................speed a) irregular b) average c) uniform d) relative 2) . If the relative speed of a car is 20 km/h relative to an observer in a bus moves in the same direction at 40 km/h, therefore the actual speed of this car is a) 20 km/h b) 40 km/h c) 60 km/h d) 80 km/h. 3) If car (A) moves at speed 80 km/h and car (B) moves at speed of 50 km/h in the same direction, the speed of car (A) relative to a passenger in car (B) is...................km/h a) 50 b) 30 c) 130 d) 80 4) An observer in a moving car with 80 km/h speed was observing a moving car with 90 km/h speed in the same direction, so the observed speed of the second car is a) 10 km/h b) 80 km/h. c) 170 km/h d) 90 km/h 5) The relative speed of a moving object relative to an observer moves at the same speed in the opposite direction is .......................the actual speed. a) double b) the same c) half d) quarter

grade 9

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