Answer:
Power_input = 85.71 [W]
Explanation:
To be able to solve this problem we must first find the work done. Work is defined as the product of force by distance.
where:
W = work [J] (units of Joules)
F = force [N] (units of Newton)
d = distance [m]
We need to bear in mind that the force can be calculated by multiplying the mass by the gravity acceleration.
Now replacing:
![W = (80*10)*3\\W = 2400 [J]](https://tex.z-dn.net/?f=W%20%3D%20%2880%2A10%29%2A3%5C%5CW%20%3D%202400%20%5BJ%5D)
Power is defined as the work done over a certain time. In this way by means of the following formula, we can calculate the required power.
where:
P = power [W] (units of watts)
W = work [J]
t = time = 40 [s]
![P = 2400/40\\P = 60 [W]](https://tex.z-dn.net/?f=P%20%3D%202400%2F40%5C%5CP%20%3D%2060%20%5BW%5D)
The calculated power is the required power. Now as we have the efficiency of the machine, we can calculate the power that is introduced, to be able to do that work.
![Effic=0.7\\Effic=P_{required}/P_{introduced}\\P_{introduced}=60/0.7\\P_{introduced}=85.71[W]](https://tex.z-dn.net/?f=Effic%3D0.7%5C%5CEffic%3DP_%7Brequired%7D%2FP_%7Bintroduced%7D%5C%5CP_%7Bintroduced%7D%3D60%2F0.7%5C%5CP_%7Bintroduced%7D%3D85.71%5BW%5D)
Making a wire thicker has the same effect as making a road wider. It makes it easier for the electron traffic to flow. The resistance decreases, and the current (traffic) increases.
Answer:
C
Explanation:
First find the electrical wattage
W = I^2 * R
R = 12 ohms
I = 2 amps
Wattage = 2^2 * 12
Wattage = 4* 12
Wattage = 48 watts.
Now you need to use the power formula
Work = Power * Time
Work = ?
Power = 48 watts
Time = 3 minutes = 3 * 60 = 180 seconds.
Work = 48 * 180
Work = 8640 J
That's C
no i dont agree, because a glass bowl is shiny but its not a metal. just because some metals are shiny doesnt make all metals shiny
Answer:
Magnetic energy and electromagnetic energy form of potential energy followed by a form of kinetic energy.
(B) is correct option.
Explanation:
Given that,
Lists a form of potential energy followed by a form of kinetic energy
We know that,
Sound energy :
The movement of energy through object it is called sound energy. When a object produced vibration by force then it moves in wave.
Sound wave is example of kinetic energy.
Nuclear energy :
The store energy in the nucleus of the atom it is called nuclear energy. This energy released when occurs fusion and fission.
Nuclear energy is the example of potential energy
Magnetic energy :
Magnetic energy is a type of potential energy which is depend on distance and position in the magnetic field.
Electromagnetic energy :
Electromagnetic energy is light energy. it is type of kinetic energy.
Gravitational energy :
Gravitational energy is a type of potential energy. It is an energy related with gravity or gravitational force.
Elastic energy :
The store energy in elastic object it is called elastic energy. This energy is a type of potential energy.
Electrical energy :
The movement of electrons is called electrical energy. When electrons move through a wire then it is are called electricity. Electrical energy is type of kinetic energy.
Hence, Magnetic energy and electromagnetic energy form of potential energy followed by a form of kinetic energy.
(B) is correct option.
