I attached the full question.
We know that for a parallel-plate capacitor the surface charge density is given by the following formula:

Where V is the voltage between the plates and d is separation.
Voltage is by definition:

Voltage is analog to the mechanical work done by the force.
Above formula is correct only If the field is constant, and we can assume that it is since no function has been given.
The charge density would then be:

Please note that elecric permittivity of air is very close to elecric permittivity of vacum, it is common to use them <span>interchangeably</span>.
(a) The net force on the shopping cart is zero.
(b) The the force of friction on the shopping cart is 25 N.
(c) When same force is applied to the shopping cart on a wet surface, it will move faster.
<h3>Net force on the shopping cart</h3>
The net force on the shopping cart is calculated as follows;
F(net) = F - Ff
where;
- F is the applied force
- Ff is the frictional force
ma = F - Ff
where;
- a is acceleration of the cart
- m is mass of the cart
at a constant velocity, a = 0
0 = F - Ff
F(net) = 0
F = Ff = 25 N
Net force is zero, and frictional force is equal to applied force.
<h3>On wet surface</h3>
Coefficient of kinetic friction of solid surface is greater than that of wet surface.
Since frictional force limit motion, when the frictional force is smaller, the object tends to move faster.
Thus, the cart will move faster on a wet surface due to decrease in friction.
Learn more about frictional force here: brainly.com/question/24386803
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Answer:
The pressure and maximum height are
and 161.22 m respectively.
Explanation:
Given that,
Diameter = 3.00 cm
Exit diameter = 9.00 cm
Flow = 40.0 L/s²
We need to calculate the pressure
Using Bernoulli effect

When two point are at same height so ,
....(I)
Firstly we need to calculate the velocity
Using continuity equation
For input velocity,




For output velocity,


Put the value into the formula



(b). We need to calculate the maximum height
Using formula of height

Put the value into the formula



Hence, The pressure and maximum height are
and 161.22 m respectively.
Answer- There are two reasons that we know quotations have been used first is the use of of name of the person who quoted it and secondly the quotation is written inside the quotation marks.
Explanation- Quotation is nothing but using a line that has been already quoted by someone somewhere. Such sentences are normally written inside quotation marks. In the above given paragraph the name of the person who quotes the sentence is also given hence we know that our quotation has been used.