Physics Review Question Unit: Year: 1991 Question#: 7 Question: A skier starting from rest straight down a slope 50. meters long in 5.0 seconds. What is the magnitude of the acceleration of the skier? (1 ) 20. m / s2 (2 ) 9.8 m / s2 (3 ) 5.0 m / s2 (4 ) 4.0 m / s2 What is this question really asking? Explanation by: Alon B [ Return to question menu ] Answer 1 20. m / s2 INCORRECT This answer is incorrect because after pluging in the correct numbers in the correct formula the answer will be different and correct. Try using the formula for change in displacement. return to top Answer 2 9.8 m / s2 INCORRECT This answer is incorrect, check the formula and numbers, you should be getting a different answer. He is not in free fall so his acceleration would not be the acceleration due to gravity. Try using . return to top Answer 3 5.0 m / s2 INCORRECT This answer is incorrect, check the formula and numbers, you should be getting a different answer. Try using return to top Answer 4 4.0 m / s2 CORRECT This answer is correct. When using the formula: you will get 4.0 m/s2 as your answer. (50m = 1/2 * a *(5s)2) return to top What's this question really asking? This question is testing to see if you can find the correct formula. There is only one formula that has displacement, initial velocity, time, and acceleration. Just make sure you plug the right numbers in the right spots. return to top This web site is designed and maintained by Science Joy Wagon and may not be reproduced or redistributed without written permission from Science Joy Wagon. Contact with comments.