Answer:
The height of the building is 88.63 m.
Explanation:
Given;
initial component of vertical velocity,
= 12 m/s sin 26° = 5.26 m/s
initial horizontal component of the velocity,
= 12 m/s cos 26° =10.786 m/s
horizontal distance traveled by the rock, x = 40.4 m
time of flight is calculated as;
x =
t
t = x / 
t = 40.4 / 10.786
t = 3.75 s
Determine the final vertical velocity of the ball;

Determine the height of the rock;

Therefore, the height of the building is 88.63 m.
Fluorite has a hardness of 4 out of 10 and can scratch gypsum, talc and anything less than 4. Fluorite has a hardness of 4 out of 10 and can scratch gypsum, talc and anything less than 4.
I think d would be the answer.
To answer the two questions, we need to know two important equations involving centripetal movement:
v = ωr (ω represents angular velocity <u>in radians</u>)
a = 
Let's apply the first equation to question a:
v = ωr
v = ((1800*2π) / 60) * 0.26
Wait. 2π? 0.26? 60? Let's break down why these numbers are written differently. In order to use the equation v = ωr, it is important that the units of ω is in radians. Since one revolution is equivalent to 2π radians, we can easily do the conversion from revolutions to radians by multiplying it by 2π. As for 0.26, note that the question asks for the units to be m/s. Since we need meters, we simply convert 26 cm, our radius, into meters. The revolutions is also given in revs/min, and we need to convert it into revs/sec so that we can get our final units correct. As a result, we divide the rate by 60 to convert minutes into seconds.
Back to the equation:
v = ((1800*2π)/60) * 0.26
v = (1800*2(3.14)/60) * 0.26
v = (11304/60) * 0.26
v = 188.4 * 0.26
v = 48.984
v = 49 (m/s)
Now that we know the linear velocity, we can find the centripetal acceleration:
a = 
a = 
a = 9234.6 (m/
)
Wow! That's fast!
<u>We now have our answers for a and b:</u>
a. 49 (m/s)
b. 9.2 *
(m/
)
If you have any questions on how I got to these answers, just ask!
- breezyツ