A brick is thrown upward from the top of a building at an angle of 25 degrees to the horizontal with an initial speed of 15 m/s. If the brick is in flight for 3 s, how tall is the building?
Answer is 25 m. How?

Question

A brick is thrown upward from the top of a building at an angle of 25 degrees to the horizontal with an initial speed of 15 m/s. If the brick is in flight for 3 s, how tall is the building?
Answer is 25 m. How?

anonymous · Answer

$$V _{x}=15\cos25=13.59m/s$$
$$V _{y}=15\sin25=6.34m/s$$
$$\Delta y=v _{0}t+\frac{ 1 }{ 2 }at ^{2}$$
$$\Delta y=(6.34)(3)+ (4.9)(3) ^{2}$$=63.12

What am I doing wrong?

anonymous · Answer

check 4th line....

anonymous · Answer

of ur solution...

anonymous · Answer

http://openstudy.com/study#/updates/504f1d09e4b07eae4f22243e

anonymous · Answer

your problem ...whether acceleration due to gravity will be + or -?
check this link...scroll down in this page...U'll see something about frame of reference.

anonymous · Answer

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