1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
SpyIntel [72]
3 years ago
8

Express the following complex numbers in the form re (a) 4 3i (b) -2 -i

Physics
1 answer:
andre [41]3 years ago
4 0

Answer:

(a) 5 {Cos 37° + i Sin 37°}

(b) 2.24 {Cos 206.6° + i Sin 206.6°}

Explanation:

(a) 4 + 3 i

Here it is written in standard form

Z = r (Cosθ + i Sinθ)

By comparison

r cosθ = 4

r sinθ = 3

Squarring both sides and then add

r^{2}=4^{2}+3^{2}=25

r = 5

By dividing

tanθ = 0.75

θ = 37°

So, it is written as 5 {Cos 37° + i Sin 37°}

(b) -2 - i

Here it is written in standard form

Z = r (Cosθ + i Sinθ)

By comparison

r cosθ = -2

r sinθ = - 1

Squarring both sides and then add

r^{2}=(-2)^{2}+(-1)^{2}=5

r = 2.24

By dividing

tanθ = 0.5

θ = 206.6°

So, it is written as 2.24 {Cos 206.6° + i Sin 206.6°}

You might be interested in
An airplane accelerates down a runmway at 2.9 m/s/s for 38.5 seconds
Serhud [2]

Given,

the initial velocity = 0 m /s.

acceleration = 3.20 m / s^2

time = 32.8 s

According to laws of motion.

s = ut + 1/2 at ^2

s = 1/2 at²

s=1/2(3.20)(32.8)²

s= 1721.344 m

the distance traveled before takeoff is 1731.3m

8 0
3 years ago
Read 2 more answers
An object that has kinetic energy must what ?
11Alexandr11 [23.1K]

An object that has kinetic energy must be <em>moving</em>.

The formula for an object's kinetic energy is

KE = (1/2) · (the object's mass) · <u><em>(the object's speed)²</em></u>

As you can see from the formula, if the object has no speed, then its kinetic energy is zero.  That's why kinetic energy is usually called the "energy of motion", and if an object HAS kinetic energy, then that tells you right away that it must be moving.

4 0
4 years ago
If we assume that, in the African savanna, the predator population remains constant, what other, nonmobile, factor would influen
musickatia [10]
On usa test prep the answer is c
7 0
3 years ago
Read 2 more answers
A steel pot has a bottom with a cross sectional area of .1m2 and has a thickness of 1cm. The pot is filled with boiling water an
jenyasd209 [6]

Answer:

840000 J/min

Explanation:

Area = A = 0.1 m²

Bottom of pot temperature = 200 °C

Thermal conductivity = k = 14 J/sm°C

Thickness = L = 1 cm = 0.01 m

Temperature of boiling water = 100 °C

From the law of heat conduction

Q = kAΔT/L

⇒ Q = 14×0.1×(200-100)/0.01

⇒ Q = 14000 J/s

Converting to J/minute

Q = 14000×60 = 840000 J/min

∴ Heat being conducted through the pot is 840000 J/min

3 0
3 years ago
How much heat h1 is transferred to the skin by 25.0 g of steam onto the skin? the latent heat of vaporization for steam is l=2.2
elena-s [515]
The heat transferred by the steam to the skin is given by
Q=m L_v
where
m is the mass of the steam
L_v is the latent heat of vaporization.

In our problem, the mass of the steam is (converting into kg)
m=25.0 g=0.025 kg
while the latent heat of vaporization of the steam is
L_v = 2.256 \cdot 10^6 J/kg
Substituting into the previous formula, we find the heat transferred to the skin:
Q=m L_v = (0.025 kg)(2.256 \cdot 10^6 J/kg)=56400 J = 2.56 \cdot 10^4 J
8 0
4 years ago
Other questions:
  • WILL GIVE BRAINLIEST PLEASE I NEED THIS! A 100-kg projectile crashes through a castle wall with a kinetic energy of 266.45 kJ. W
    10·1 answer
  • Noah drops a rock with a density of 1.73 g/cm3 into a pond. Will the rock float or sink? Explain your answer.
    10·2 answers
  • Driving along a crowded freeway, you notice that it takes a time t to go from one mile marker to the next. When you increase you
    6·2 answers
  • Compare and contrast four types <br> of friction
    9·1 answer
  • A vector has an x component of 25.0 units and a y
    14·1 answer
  • Is jacob barnes a turd face?
    12·2 answers
  • Write down short notes on:<br>c. Power​
    10·1 answer
  • What is the kinetic energy of a bicycle with a mass of 16 kg traveling at a velocity of 5 m/s
    6·1 answer
  • Objects 1 and 2 attract each other with a gravitational force of 12 units. If the mass of Object 2 is tripled, then the new grav
    8·1 answer
  • Question is in the picture below
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!