The average radius(r) of each grain is r = 50 nanometers
= 50*10^-6 meters
Since it is spherical, so
Volume=(4/3)*pi*r^3
V= (4/3)*pi*(50*10^-6)^3
V=5.23599*10^-13 m^3
We are given the Density(ρ) =2600kg/m^3
We know that:
Density(p) = mass(m)/volume(V)
m = ρV
So the mass of a single grain is:
m = 5.23599*10^-13 * 2600 = 1.361357*10^-9 kg
The surface area of a grain is:
a = 4*pi*r^2
a = 4*pi*(50*10^-6)^2
a = 3.14*10^-8 m^2
Since we know the surface area and mass of a grain, the
conversion factor is:
1.361357*10^-9 kg / 3.14*10^-8 m^2
Find the Surface area of the cube:
cube = 6a^2
cube = 6*1.1^2 = 7.26m^2
multiply this by the converions ratio to get:
total mass of sand grains = (7.26 m^2 * 1.361357*10^-9 kg)
/ (3.14*10^-8 m^2)
total mass of sand grains = 0.3148 kg = 314.80 g
The gravitational potential energy
gpe = mgh

Any type of physical act isn’t a emotional reaction. Things like crying or yelling or getting mad at yourself is emotional. Changes in your activity level, change in eating, sleeping, sense of humor. Increased uses in tobacco or drugs, when you’re becoming accident prone, when you’re not able to relax, when your heart rate increases, headaches, startled easily, when you’re tired all the time and sleep doesn’t help (fatigue). For women your period might change. When you get lower back pain, upset stomach, flare ups that are associated with allergies asthma or arthritis and if you get sick easier. If you lose more hair than normal for your body. If you’re blood pressure is up. Things like this is physical. You might find people will isolate themselves or blame themselves. They may have a difficulty concentrating. You can look up so many ways that stress can affect a person physically
Answer:
Heyyy hope this helps
Convection currents describe the rising, spread, and sinking of gas, liquid, or molten material caused by the application of heat.
Explanation:
If a positive test charge is placed in an electric field, it will exert the force in the test charge in the direction of electric field vector. We know that the direction of electric field is given by electric field lines. The field lines for a positive charge is outwards. The electric force acting on the charge is given by :
F = q E
Hence, this is the required solution.