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Stuy
unit circle?
Write the following expression as a function of a positive acute angle. Use "+" to indicate a positive value a negative value.
sin312° =_____a0
sin_______a1
taking an online course and I didn't understand this question... needless to say i got i wrong but i don't understand it still and it doesn't show me the right answer. I am afraid I might get it again.
thank you in advance
2 AnswersMathematics7 years agoWhat are the phrases "Family Tree" or "Moral Compass" called?
like an onomatopoeia is a word that sounds like a sound... Do these well known phrases that connect something that is purely conceptual to an object. If not, what other ones are there?
2 AnswersPoetry7 years agocos^2(x)+sin=1 How to solve?
7 AnswersMathematics8 years agohow could i rewrite cos^4(x) using sum of power formulas?
1 AnswerMathematics8 years agoI am doing a science reveiw and i dont know if I am even studying right, I put in my answers, are they right?
18. A coil of wire that is carrying a current and produces a magnetic field is
a galvanometer.
a solenoid.---
a magnetic domain.
an electric motor.
19. Which of the following is the reason “soft” iron is used for the cores of electromagnets?
It is difficult to magnetize.
It is easily magnetized.---
It has no magnetic domains.
It is a permanent magnet.
20. The device that measures current in a wire by using the deflections of an electromagnet in an external magnetic field is
a galvanometer.
a solenoid.
an electric motor.---
a loudspeaker.
21. The electromagnet in a galvanometer
increases the voltage in a circuit.
moves a pointer along a numbered scale in response to a current.---
induces an electric current.
increases the current in a circuit.
22. In an electric motor, periodically changing the direction of current in the electromagnet can cause the axle to spin because
the electromagnet loses its magnetism.
mechanical energy is converted to electric energy.
the moving electrons push the electromagnet in the opposite direction.---
the magnetic field reverses direction.
23. Moving a magnet inside a coil of wire will induce a voltage in the coil. How can the voltage in the coil be increased?
Move the magnet inside the coil of wire more slowly.
Hold the magnet stationary.
Move the coil of wire slowly, and keep the magnet stationary.
Move the magnet inside the coil of wire more rapidly.---
24.
The process of generating an electric current by moving an electrical conductor relative to a magnetic field is called (1 point)
magnetization. ---
electromagnetic force.
electromagnetic induction.
alternating current.
25.
A device that changes mechanical energy to electrical energy by rotating a coil of wire through a magnetic field is called a(n) (1 point)
transformer. ---
generator.
electromagnet.
current meter.
26.
A DC generator is similar to an AC generator except that in (1 point)
DC generators, slip rings produce direct current.
DC generators, commutators produce direct current.
AC generators, commutators produce alternating current.
AC generators, no commutators or slip rings are used.---
27.
A transformer has a primary coil with 600 turns and a secondary coil with 300 turns. If the output voltage is 320 volts, what is the input voltage? (1 point)
8 volts
150 volts ---
640 volts
600 volts
28.
How are step-up transformers used in the transmission of electrical energy? (1 point)
They increase the voltage and the current for a home. ---
They decrease the voltage before it leaves a power plant.
They increase the voltage for efficient long-distance transmission.
all of the above
Thanks in advance
1 AnswerHomework Help9 years agoI am doing a science reveiw and i dont know if I am even studying right, I put in my answers, are they right?
1. If an atom gains electrons, it becomes a
positively charged ion.
negatively charged ion.---
neutral atom.
neutral ion.
2. If a neutral metal comb is held near an object with a negative charge, the comb will become charged by
induction.---
contact.
friction.
static discharge.
3. What type of current is produced by a battery?
parallel current
alternating current
direct current---
potential current
4. An electrical insulator has
electrons that freely move.
more protons than electrons.
negatively charged ions.
electrons tightly bound to its atoms.---
5. Which of the following would reduce the resistance of a metal wire?
increasing its thickness---
increasing its temperature
increasing its length
all of the above
6. What is the difference in electrical potential energy between two places in an electric field?
current
resistance
potential difference---
induction
7. Which of the following is maintained across the terminals of a battery?
a potential difference
a voltage drop
an electric charge---
both the first and second choices above
8. If you know the power rating of an appliance and the voltage of the line it is attached to, you can calculate the current the appliance uses by
multiplying the voltage by the power.
subtracting the power from the voltage.
dividing the voltage by the power.---
dividing the power by the voltage.
9. A ground-fault circuit interrupter shuts down a circuit if it
melts.
senses an overload.---
senses unequal currents.
senses moisture.
10. A solid-state component with three layers of semiconductors is a(n)
transistor.---
diode.
vacuum tube.
resistor.
11. The force a magnet exerts on another magnet, on iron or a similar metal, or on moving charges is
an electric force.
a magnetic force.---
proportional to the charge of the magnet.
proportional to the mass of the magnet.
12. Which of the following statements describes the interaction between magnetic poles?
Like poles attract each other.
Like poles repel each other, and opposite poles attract each other.
Opposite poles repel each other.
Like poles attract each other, and opposite poles repel each other.---
13. Which of the following statements is true about Earth’s magnetic poles?
They are located at Earth’s geographic poles.
They are the areas where Earth’s magnetic field is weakest.
They are the areas where Earth’s magnetic field is strongest.---
Earth has four magnetic poles.
14. A ferromagnetic material that has domains that remain aligned for a long period of time is called
a neutral object.
nonmagnetic.
a permanent magnet.---
a temporary magnet.
15. How can a permanent magnet be demagnetized?
Cut the magnet in half.
Heat the magnet up.---
Strike the magnet with a heavy blow.
both the second and third choices above
16. If the current in a wire is directed upward, what is the direction of the magnetic field produced by the current?
counterclockwise in the horizontal plane
clockwise in the horizontal plane
in the same direction as the current
in the opposite direction to the current---
17. If a current-carrying wire is in a magnetic field, in what direction will a force be exerted on the wire?
perpendicular to the magnetic field and parallel to the current direction
parallel to both the current direction and the magnetic field
perpendicular to the current direction and parallel to the magnetic field---
perpendicular to both the magnetic field and the current direction
I know its a lot and its only half the study guide, ill be posting the other half because i dont know if I'm studing the right answers.
1 AnswerHomework Help9 years ago8. Romeo curses his _____ for the events of the play.?
Im doing a romeo and juliet themed crossword and i am stuck on this one, i know the second leter is an "A" and its a a 4 letter word
2 AnswersTheater & Acting9 years agoevaluating infinant geometric series?
I have 2 geometric series that I am struggling with, i need to evaluate them and I dont know how.
∞
Σ(-1/2)^(n-1)
n=1
and
∞
Σ3(.4)^(n-1)
n=1
3 AnswersMathematics9 years agoRational Expressions.?
Im having trouble simplifying these... how would I do it?
1.
(x^2/x^2+2x+1)/(3x/x^2-1)
2. (2x+4/3x-3)*(12x-12/x+5)
3. (7/2xy^2)+(3/8x^2y)
4. (x^2-16/2x+8)/((x-4)^2/8x-32)
5. 5-(4x^2-5x+1/x^2-x)
6. 1/3x/5/6y
3 AnswersMathematics9 years agoWrite the expression as a single natural logarithm.?
3 in a -1/2(in b +in c^2)
1 AnswerMathematics9 years ago