20 12 Pat measures the speeds of two cars.

The diagram shows the speeds of the cars. car A

speed of car A = 9 m/s (a)

car B

speed of car B = 15 m/s

Calculate the relative velocity of car A and car B. ..................................................................................................................................................... ..................................................................................................................................................... Answer.................................................................................................................................... [1]

(b)

Car A accelerates and, after 4 seconds, is travelling at the same speed as Car B. Calculate the acceleration of car A. ..................................................................................................................................................... ..................................................................................................................................................... Answer.......................................................................................................Units..................[1]

ÂŠ OCR 2011

SPECIMEN

P3 question 12 (1)