Speed Time & Distance Question Answers

Speed, Time and Distance - Quant/Math - CAT 2008

Question 4 the day: September 23, 2002
The question for the day is from the topic of Speed, Time and Distance.

When an object is dropped, the number of feet N that it falls is given by the formula N = �gt² where t is the time in seconds from the time it was dropped and g is 32.2. If it takes 5 seconds for the object to reach the ground, how many feet does it fall during the last 2 seconds?

(1)

64.4

(2)

96.6

(3)

161.0

(4)

257.6

Correct Answer - (4)

 

---

Solution:

In 5 seconds it travels
� * 32.2 * 5² = 16.1 * 25 = 402.5
In first 3 seconds it travels
� * 32.2 * 3² = 16.1 * 9 = 144.9
Hence in the last 2 seconds it traveled 402.5 - 144.9 = 257.6