Answer:
The velocity at impact is 222.2 m/s
Explanation:
The given information are;
The time at which the woman heard the sound of the coin after dropping it into the wishing well = 30 seconds
The average speed of sound in air = 344 m/s
The time in which the dime travel = t₁
The time in which the sound travel = t₂
1/2 × 9.8 × t₁² = 344 × t₂
t₁ + t₂ = 30
4.9·t₁² = 344 × (30 - t₁)
4.9·t₁² + 344·t₁ - 10320 = 0
Which gives -344±
t₁ = 22.676 seconds or -92.9 seconds
Therefore the correct natural time is t₁ = 22.676 seconds
The velocity at impact, v = g×t₁ = 9.8 × 22.676 = 222.2 m/s
The velocity at impact= 222.2 m/s.
Answer
given,
position of particle
x(t)= A t + B t²
A = -3.5 m/s
B = 3.9 m/s²
t = 3 s
a) x(t)= -3.5 t + 3.9 t²
velocity of the particle is equal to the differentiation of position w.r.t. time.
------(1)
velocity of the particle at t = 3 s
v = -3.5 + 7.8 x 3
v = 19.9 m/s
b) velocity of the particle at origin
time at which particle is at origin
x(t)= -3.5 t + 3.9 t²
0 = t (-3.5 + 3.9 t )
t = 0, 
t = 0 , 0.897 s
speed of the particle at t = 0.897 s
from equation (1)
v = -3.9 + 7.8 t
v = -3.9 + 7.8 x 0.897
v = 3.1 m/s
the Republic of South Africa country is being described by these statements
<u>Explanation:</u>
South Africa has the highest amount of people living with HIV/AIDS in the world. It was initially identified in 1982. The ANC came to power in 1994 after ten years of National Party inaction concerning AIDS. The ANC although took province with a formidable strategy, on record at least, for speaking HIV/AIDS.
A National AIDS Convention of South Africa (NACOSA), first gathered in 1992, brought collectively the ANC, the ANC-aligned United Democratic Front, and the National Party government’s ministry of health, to develop a comprehensive 1994 national AIDS plan based on robust projections: ‘HIV/AIDS is emerging as a major public health problem, with over 2,000 reported cases at the end of 1993, and 500,000 people infected with HIV’.
Albert Vanfleet i know this because he flew over in 1976 and found a job studying physics. He became well known for his work in 1983.
