Answer:
They had different beliefs and backgrounds.
Explanation:
Ptolemy believed in geocentric model of the solar system -the earth at the center and the sun, other planets and stars revolved about it. His belief was based on his observation that sun and other objects in sky seemed to revolve about the Earth as they rose and set in one day.
Copernicus while reading a book, constructed the theory of heliocentric system which was later proved through observations.
Well,
A control in an experiment would basically be the "normal" version of your test subjects.
In a drug testing experiment with people, the control group would be the people who don't take the drug.
In an experiment on the effects of salt on potatoes, the control group would be a potato without salt on it.
So in an experiment to measure the effects of gas additives on fuel, the control would be fuel without additives.
M = 10.0 g, the mass of the iron sample
ΔT = 75 - 25.2 = 49.5°C, the decrease in temperature
c = 0.449 J/(g-°C), the specific heat of iron
The heat released is
Q = m*c*ΔT
= (10.0 g)*(0.449 J/(g-°C))*(49.5 C)
= 222.255 J
Answer: 222.3 J (nearest tenth)
Part (a): Velocity of the snowball
By conservation of momentu;
m1v1 + m2v2 = m3v3,
Where, m1 = mass of snowball, v1, velocity of snowball, m2 = mass of the hat, v2 = velocity of the hat, m3 = mass of snowball and the hat, v3 = velocity of snowball and the hut.
v2 = 0, and therefore,
85*v1 + 0 = 220*8 => v1 = 220*8/85 = 20.71 m/s
Part (b): Horizontal range
x = v3*t
But,
y = vy -1/2gt^2, but y = -1.5 m (moving down), vy =0 (no vertical velocity), g = 9.81 m/s^2
Substituting;
-1.5 = 0 - 1/2*9.81*t^2
1.5 = 4.905*t^2
t = Sqrt (1.5/4.905) = 0.553 seconds
Then,
x = 8*0.553 = 4.424 m
