Explanation:
Initial energy = final energy + work done by friction
PE = PE + KE + W
mgH = mgh + 1/2 mv² + W
(800)(9.8)(30) = (800)(9.8)(2) + 1/2 (800) v² + 25000
v = 22.1 m/s
Without friction:
PE = PE + KE
mgH = mgh + 1/2 mv²
(800)(9.8)(30) = (800)(9.8)(2) + 1/2 (800) v²
v = 23.4 m/s
This group is called “noble gases” because they do not react with other elements. This is because they have a full valence shell.
Answer:
λ = 596 nm.
Explanation:
Fringe width = λ D / d
λ is wave length , D is screen distance and d is slit separation.
Putting the values
1.62 x 10⁻² =( λ x 5.3 ) / .195 x 10⁻³
λ = 596 nm.
Answer:
1. Kinetic Energy = 0.0161 Joules
2. Height = 0.0137m
Explanation:
Given
Length of Rod, l = 0.64m
Mass, m = 120g = 0.12kg
Angular speed, w = 1.40 rad/s
a.
Calculating the Rod's kinetic energy
This is calculated by
Kinetic Energy = ½Iw²
Where I = rotational inertia of the rod about an axis.
This is calculated as follows;
I = Icm + mh²
I = ImL² + m(L/2)²
I = 1/12 * 0.12 * 0.64² + 0.12 * (0.64/2)²
I = 0.016384 kgm²
By substituton
KE = ½Iw² becomes
KE = ½ * 0.016384 * 1.40²
KE = 0.01605632J
KE = 0.0161 Joules
2. Using the total conservation of momentum;
K + U = Kf + V
Where K = Initial Kinetic Energy of the rod at lowest point.
U = Initial gravitational potential energy of the rod at lowest point
Kf = Final Kinetic Energy of the rod at maximum height = 0 J
V = Final gravitational potential energy of the rod at maximum height
So, K + U = Kf + V become
K + U = 0 + V
K + U = V
K = V - U = mgh
substitute 0.01605632J for K
0.01605632J = mgh
h = 0.01605632J/mg
h = 0.01605632J/(0.12 * 9.8)
h = 0.013653333333333
h = 0.0137m
Answer:
1. 100 CE
Menelaus of Alexandria lived. a Greek mathematician and astronomer
2. 190 BCE - 120 BCE
Hipparchus of Nicea, an Hellenic language mathematician, astronomer and geographer, regarded by many historians as a scientist of the most effective quality and one amongst the most effective astronomical genius amongst ancient Greeks.
3. 276 BCE - 195 BCE
Eratosthenes, an Hellenic language Alexandrian scholar, who was a native of Cyrene and one amongst the most effective geographers in antiquity.
4. c. 310 BCE - c. 230 BCE
Aristarchus of Samos. A Greek astronomer and mathematician
5. 384 BCE - 322 BCE
Aristotle Era.
6. c. 571 BCE - c. 497 BCE
Pythagoras of Samos lived during this era.
7. 585 BCE
Media and Lydia went into battle and broke off immediately as a result an entire eclipse of the sun which occurred causing the two armies to create peace. The eclipse was already predicted by Thales of Miletus.
8. 585 BCE
Thales of Miletus lived during now.
Explanation:
Ancient Greeks were some of the first people known to study the sky and understand what astronomy really entails. They discovered the Earth was spherical in shape and went ahead to devise a means to measure its size. They also were the ones who created the idea of a geocentric solar system, which was incorrect, But assisted us in understanding the universe for over hundreds of years.
