Answer:
Explanation:
Given data
time=0.530 h
Average velocity Vavg=19.0 km/s
To find
Displacement Δx
Solution
The Formula for average velocity is given as
Given that,
Initial velocity , Vi = 0
Final velocity , Vf = 40 m/s
Acceleration due to gravity , a = 9.81 m/s²
Distance can be calculated as,
2as = Vf² - Vi²
2 * 9.81 *s = 40² - 0²
s = 81.55 m
For half height, that is, s = 40.77m
Vf= ??
2as = Vf² - Vi²
2 * 9.81 * 40.77 = Vf² - 0²
Vf² = 800
Vf = 28.28 m/s
Therefore, speed of roller coaster when height is half of its starting point will be 28 m/s.
Answer:
A. Kinetic energies are equal.
Explanation:
The kinetic energy of the bodies will be equal since the mass and speed are the same.
Kinetic energy is the energy due to the motion of a body.
Mathematically;
K.E = 
m v²
m is the mass
v is the speed
The kinetic energy is a scalar quantity with no regard for direction.
The correct answer is silver metal.
Conductivity measures the ability of a material or a metal to transmit energy, conductivity may be electrical, thermal or acoustical conductivity. The most electrical conductive element is silver, followed by copper and Gold. Silver also has the highest thermal conductivity as compare to any element. However, copper and Gold are more often used in electrical applications since copper is less expensive and gold has a much higher corrosion resistance.
