Answer:
F' = (4/9)F
Explanation:
The electrostatic force between two charged objects is given by Coulomb's Law:
F = kq₁q₂/r² -------------------- equation (1)
where,
F = Electrostatic Force
k = Coulomb's Constant
q₁ = magnitude of first charge
q₂ = magnitude of second charge
r = distance between charges
Now, when the charges and distance altered as follows:
q₁' = 2q₁
q₂' = 2q₂
r' = 3r
Then,
F' = kq₁'q₂'/r'²
F' = k(2q₁)(2q₂)/(3r)²
F' = (4/9)kq₁q₂/r²
using equation (1):
<u>F' = (4/9)F</u>
Answer:
(2) The excess negative charge from the sphere spread out all over your body.
(7) After you touched it, the metal sphere was very nearly neutral.
Explanation:
Plastic pen repels magic tape so magic tape is also negatively charged . Further , magic tape repels small metal sphere that means small sphere also is negatively charged.
Now when small sphere is touched by a man insulated from ground , the charge is distributed between man and small sphere according to their capacitance .
Since human body will have greater capacitance ,it will acquire larger share of charge . Sphere being of very small size will retain very less charge and it will become almost neutral . Hence it will be attracted by charged tape .
The answers are B, C, E and F.
Atoms from an element is mostly made of protons, neutrons, and electrons. Proton numbers are like a class number for each element. Each element has their own and they're all different. And the number of protons are equal to the number of electrons. Therefore, B is correct.
Isotopes. It's different atoms from a same element that has the same number of protons but different number of neutrons. For example in hydrogen, there's 3 Isotopes for hydrogen. Therefore, C is correct.
Again, proton for the same element is never changed, even if they're different Isotopes. So, E is correct.
Isotopes, again, different elements may have different Isotopes. Some has only 1, others may have a few or more. So, F is correct too.
Answer:
This is because the acceleration of objects due to gravity is independent of the mass of the object and is constant for all objects, therefore, all objects fall with the same speed.
Explanation:
The weight of an object or force of gravity acting on an object on the surface of earth is a product of its mass and acceleration due to gravity.
Mathematically, w = mg
where, m=mass of the object; g = acceleration due to gravity
Also, from newton's law of gravitation, gravitational force on the object ,F = GMm/r²
where G is the gravitational constant; M is mass of Earth; m is mass of object; r is the distance of separation between the object and the center of mass of the earth which is approximately the radius of earth.
Since the weight of an object is equal to the force of gravitation acting on it
W = F
mg = GMm/r²
g = GM/r²
The expression above is that of the relationship between the force of gravity acting on a body on the earth's surface, the weight of that body and the acceleration due to gravity, g.
It can be seen that the acceleration due to gravity g is independent of the mass of the object. Therefore, the acceleration of objects due to gravity is constant for all objects and all objects fall with the same speed.
Vector quantities have both magnitude and direction. Distance is a scalar quantity. It refers only to how far an object has traveled. For example, 4 feet is a distance; it gives no information about direction.
