Answer:
Hi... Potential energy is converted to kinetic energy and kinetic energy is converted to potential energy
Answer:
The circumference of the Earth is 24818.58 miles
Explanation:
Analysis conceptual : The formula of the circumference is the following:
L= π*D Formula (1)
Where:
L : is the length of the circumference in miles (mi)
π : is the constant
D : is the diameter of the circumference in miles (mi)
Known data
π = 3.1416
D= 7900 miles: Diameter of the Earth
Problem development
We apply the formula 1 to calculate the circumference of the Earth (L):
L= π*7900 miles
L= 24818.58 miles
Answer:

Explanation:
consider the mass of each train car be m
m₁ = m₂ = m₃ = m
speed of the three identical train
u₁ = u₂ = u₃ = 1.8 m/s
m₄ = m u₄ = 4.5 m/s
m₅ = m u₅ = 0 (initial velocity )
final velocity
v₁ = v₂ = v₃ = v₄ = v₅ = v
using conservation of momentum
m₁u₁ + m₂u₂ + m₃u₃ + m₄u₄ + m₅u₅ = m₁v₁ + m₂v₂ + m₃v₃ + m₄v₄ + m₅v₅
m (1.8 + 1.8 + 1.8 +4.5) = 5 m v


Answer: choices a and b
Explanation:
Telescope can be defined as am optical instrument which is designed to observe the distant objects clear and nearer. It comprises of arrangement of lenses which allow the rays of light to be collected. The collected light is focused and the image so produced is magnified in the form of an image. The telescopes are prepared and manufactured on mountains top as this will help in preventing the distortion of light obtain from the star due to the fluctuation of air mass in the atmosphere. The atmospheric distortion affects the resolution, and affects the vision. The atmospheric pressure is low at the mountain tops so it will help in better observation of the sky.