Answer:
400 N
Explanation:
By the law of friction,
is the maximum frictional force, 
is the coefficient of friction and 
is the reaction on the refrigerator. On a horizontal surface, the reaction is equal to the weight of the refrigerator.
While not moving, the fricition on the refrigerator is static friction. So, 
This is the maximum frictional force and is more than the applied horizontal force of 400 N. Frictional force cannot be more than the applied force, else it would actually pull the refrigerator backwards (a strange thing, if it were to happen). It is equal to the extent of the applied force because the applied force is not enough to overcome the maximum.
Hence the frictional force is 400 N.
PS: Note that we do not use the coefficient of kinetic friction because applied force could not overcome the static friction.
Answer:
16.8ohms
Explanation:
According to ohm's law which states that the current passing through a metallic conductor at constant temperature is directly proportional to the potential difference across its ends.
Mathematically, V = IRt where;
V is the voltage across the circuit
I is the current
R is the effective resistance
For a series connected circuit, same current but different voltage flows through the resistors.
If the initial current in a circuit is 19.3A,
V = 19.3R... (1)
When additional resistance of 7.4-Ω is added and current drops to 13.4A, our voltage in the circuit becomes;
V = 13.4(7.4+R)... (2)
Note that the initial resistance is added to the additional resistance because they are connected in series.
Equating the two value of the voltages i.e equation 1 and 2 to get the resistance in the original circuit we will have;
19.3R = 13.4(7.4+R)
19.3R = 99.16+13.4R
19.3R-13.4R = 99.16
5.9R = 99.16
R= 99.16/5.9
R = 16.8ohms
The resistance in the original circuit will be 16.8ohms
Answer:
The answer to this question is given below in this explanation section.
Explanation:
" law of conservation of energy"
The law of conservation of energy states that energy can neither be created nor destroyed only converted from one form of energy into another.This mean that a system always has a same account of a energy,unless it is added from the outside.This is particularly confusing in the case of non conversation forces,where energy is converted from ,mechanical energy into thermal energy.but the overall energy does remain the same.The only way to use energy is to transform energy from one form to another.
The amount of energy in any system than it is determined by the following equation.
Ut=Ui +W+Q
- Ut is the total internal energy of a system.
- Ui is the initial internal energy of a system.
- W is the work done by or on the system.
- Q is the heat added to or removed by the system.
It is also possible to determined the change in internal energy of the system using the equation.
ΔU=W+Q
The mechanical energy of a system increases provided their is no loss of energy due to friction.The energy would transform to kinetic energy when the speed is increasing.Te mechanical energy of a system remain constant provided their is no loss of energy due to friction.
The law of conversation of energy which say that in a closed system total energy is conserved that is it constant.
KE1 + PE1=KE2+PE2
For E = 200 gpa and i = 65. 0(106) mm4, the slope of end a of the cantilevered beam is mathematically given as
A=0.0048rads
<h3>What is the slope of end a of the cantilevered beam?</h3>
Generally, the equation for the is mathematically given as
Therefore
A=\frac{10+10^2+3^2}{2*240*10^9*65*10^6}+\frac{10+10^3*3}{240*10^9*65*10^{-6}}
A=0.00288+0.00192=0.0048rads
A=0.0048rads
In conclusion, the slope is
A=0.0048rads
Read more about Graph
brainly.com/question/14375099
The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet that needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field.
