Answer:
The change in the charge on the positve plate when the Teflon is inserted is +2.5 nC.
Explanation:
- It can be showed that the capacitance of a parallel-plate capacitor, can be expresssed as follows:

- Where ε, is the dielectric constant of the material that fills the space between plates.
- When this space is filled with air, ε= ε₀ = 8,85*10⁻¹² F/m.
- At the same time, the capacitance of a capacitor, by definition, is as follows:

- If we insert a Teflon slab, in such a way that fills completely the gap between the plates, all other parameters being equal, if ε = 2*ε₀, this means that C₂ = 2* C₁. = 50 pF
- As V₂=V₁ (due to the capacitor remains connected to the same battery) the charge must be the double, so Q₂ = 2* Q₁ = 5 nC.
- So, the change in the charge of the positive plate is +2.5 nC.
Explanation:
It is given that,
Mass of the object, m = 0.8 g = 0.0008 kg
Electric field, E = 534 N/C
Distance, s = 12 m
Time, t = 1.2 s
We need to find the acceleration of the object. It can be solved as :
m a = q E.......(1)
m = mass of electron
a = acceleration
q = charge on electron
"a" can be calculated using second equation of motion as :




a = 16.67 m/s²
Now put the value of a in equation (1) as :


q = 0.0000249 C
or

Hence, this is the required solution.
Your grade will probably go down to a D 68% or little higher than that
Answer: 
Explanation:
According to Newton's law of universal gravitation:
Where:
is the module of the force exerted between both bodies
is the universal gravitation constant.
and
are the masses of both bodies.
is the distance between both bodies
In this case we have two situations:
1) Two bags with masses
and
mutually exerting a gravitational attraction
on each other:
(1)
(2)
(3)
2) Two bags with masses
and
mutually exerting a gravitational attraction
on each other (assuming the distance between both bags is the same as situation 1):
(4)
(5)
(6)
Now, if we isolate
from (3):
(7)
Substituting
found in (7) in (6):
(8)
(9)
Simplifying, we finally get the expression for
in terms of
:
D. <span>When placed together in pairs for study, no pair of Abert's squirrel and Kaibab squirrel result in offspring.</span>