Answer:
In order to make this force twice as strong, F' = 2 F, the distance would have to be changed to half i.e. r' = r/2.
Explanation :
The electric force between two point charges is directly proportional to the product of charges and inversely proportional to the square of the distance between charges. It is given by :
r is the separation between charges
If F'= 2F
In order to make this force twice as strong, F' = 2 F, the distance would have to be changed to half i.e. . Hence, this is the required solution.
Explanation:
The velocity of sound depends on the density of the medium. So we need to find the density of air at each set of conditions. The density of air is:
ρ = (Pd / (Rd T)) + (Pv / (Rv T))
where Pd and Pv are the partial pressures of dry air and water vapor,
Rd and Rv are the specific gas constants of dry air and water vapor,
and T is the absolute temperature.
At the first condition:
Pv = 31.7 mmHg = 4226.3 Pa
Pd = 650 mmHg - 31.7 mmHg = 618.3 mmHg = 82433 Pa
Rv = 461.52 J/kg/K
Rd = 287.00 J/kg/K
T = 30°C = 303.15°C
ρ = (82433 / 287.00 / 303.15) + (4226.3 / 461.52 / 303.15)
ρ = 0.94746 + 0.03021
ρ = 0.97767 kg/m³
At the second condition:
Pv = 0 Pa
Pd = 650 mmHg = 86660 Pa
Rv = 461.52 J/kg/K
Rd = 287.00 J/kg/K
T = 0°C = 273.15°C
ρ = (86660 / 287.00 / 273.15) + (0 / 461.52 / 273.15)
ρ = 1.1054 + 0
ρ = 1.1054 kg/m³
The square of the velocity of sound is proportional to the ratio between pressure and density:
v² = k P / ρ
Since the atmospheric pressure is constant, we can say it's proportional to just the density:
v² = k / ρ
Using the first condition to find the coefficient:
(340)² = k / 0.97767
k = 113018.652
Now finding the velocity of sound at the second condition:
v² = 113018.652 / 1.1054
v = 319.75
Answer:
Hematite and magnetite
Explanation:
Minerals such as Iron don’t occur alone due to its interaction with other elements. The Iron’s major source is usually through ores such as Hematite, Magnetite, limonite etc.
However Pure magnetite contains 72.4 percent iron and pure hematite contains 69.9 percent. They have the highest percentage of iron thereby making them the main sources.
Answer:
False
Explanation:
According to USA today "Though nearly 60% of the 18 to 21 year olds surveyed said they have a job, and 70% of the 22 to 26 year olds said the same, many seem to rely on mom and dad to fund non-essential expenses. Nearly 75% of the 18 to 21 year olds and more than 40% of 22 to 26 year olds said their parents pay their monthly cell phone bill. Just 54% of 22 to 26 year olds own or lease their own car; and 43% of 22 to 26 year olds are living at home with their parents."
Answer:
Hope this help you!!
Explanation:
Crust : The crust is the thinnest layer of the Earth. It has an average thickness of about 18 miles below land, and around 6 miles below the oceans. The crust is the layer that makes up the Earth's surface and it lies on top of a harder layer, called the mantle.
Mantle : The mantle is the mostly-solid bulk of Earth's interior. The mantle lies between Earth's dense, super-heated core and its thin outer layer, the crust. The mantle is about 1,802 miles thick, and makes up a whopping 84% of Earth's total volume
Outer Core : The outer core is the third layer of the Earth. It is the only liquid layer, and is mainly made up of the metals iron and nickel, as well as small amounts of other substances. The outer core is responsible for Earth's magnetic field. As Earth spins on its axis, the iron inside the liquid outer core moves around.
Inner Core : It's Almost The Size of the Moon. The Earth's inner core is surprisingly large, measuring 1,516 miles across. It's Mostly Made of Iron. It Spins Faster Than the Surface of the Earth. It Creates a Magnetic Field.
