Answer:
[tex]0.005847\ \text{s}[/tex]
Explanation:
Radio waves travel at the speed of light
[tex]c[/tex] = Speed of light = [tex]3\times 10^8\ \text{m/s}[/tex]
[tex]d_r[/tex] = Distance between two radios = 46 km
[tex]v[/tex] = Speed of sound in air = 348 m/s
[tex]d_s[/tex] = Distance sound travels across the newsroom = 2.1 m
Time taken by the radio signal to reach the required location is
[tex]t_r=\dfrac{d_r}{c}\\\Rightarrow t_r=\dfrac{46\times 10^3}{3\times 10^8}\\\Rightarrow t_r=0.000153\ \text{s}[/tex]
Time taken by sound to reach the required location is
[tex]t_s=\dfrac{d_s}{v}\\\Rightarrow t_s=\dfrac{2.1}{348}\\\Rightarrow t_s=0.006\ \text{s}[/tex]
The time difference is
[tex]t_s-t_r=0.006-0.000153=0.005847\ \text{s}[/tex]
The difference in time that the message is received is [tex]0.005847\ \text{s}[/tex].
PLEASE HELP ME WITH THIS ONE QUESTION
What is the final temperature when 625 grams of water at 75.0° C loses 7.96 x 10^4 J? (cwater = 4186 J/kg°C)
Answer:
T_f = 44.6 ° C
Explanation:
We can solve this exercise using the calorimetry relations
Q = m c_e ΔT
ΔT = [tex]\frac{Q}{m \ c_e}[/tex]
let's calculate
ΔT = -7.96 10⁴ /(0.625 4186)
ΔT = -3.04 10¹
The negative sign indicates that the temperature decreases
the temperature variation is
T_f - T₀ = ΔT
T_f = T₀ + ΔT
T_f = 75.0 - 30.4
T_f = 44.6 ° C
PLZ HELP PLZ ILL GIVE BRAINLIEST TO BEST ANSWERED
The Earth's gravity pulling on a skydiver: Contact or Non Contact
Friction from a car's brakes causing it to stop: Contact or Non Contact
The repulsive magnetic force between the north poles of two magnets: Contact or Non Contact
The attractive electrostatic force between an electrically charged balloon and a wall: Contact or Non Contact
Answer:
1.Contact because its a contact force
2 Contact because when the car is stopping it is coming in to contact with the ground.
3 non Contact because magnets don't need to have contact they pull
4 non Contact because its not a contact force
How do sociologists view the categories of race, class, and gender?
Multiple Choice
1. inherent and inevitable
2. socially constructed
3. unchangeable and perpetual
4. natural and biologically determined
Answer:
2. Socially constructed
Explanation:
who compose the Ghana national anthem
Answer:
Philip Gbeho
Explanation:
A human body consists of
Answer:
60% of the human adult body is water. According to H.H. Mitchell, Journal of Biological Chemistry 158, the brain and heart are composed of 73% water, and the lungs are about 83% water. The skin contains 64% water, muscles and kidneys are 79%, and even the bones are watery: 31%.
Explanation:
Which phrase best completes the diagram?
Role of the Federal Reserve in the U.S. economy:
Sets interest rates➡️?➡️Loans money to other banks
A. Approves the federal budget.
B. Votes on coporate regulations.
C. Sets the consumer price index.
D. Makes rules for other banks.
Correct answer is:
D. Makes rules for other banks.
Answer:
B
Explanation:
i think
Answer:
D. makes rules for other banks
Explanation:
Three 5 Ohm resistors are connected in parallel to a 9 Volt power supply. What is the current through each resistor?
Answer:
I₁ = I₂ = I₃ = 12 A
Explanation:
Since the resistors are connected in parallel across a battery. Hence, the voltage across each of them will be the same, which will be equal to the voltage of the power supply. Since each resistor has the same resistance of 5 Ω. Therefore. the current across each resistor will also be the same. We can easily calculate these current values by the use of Ohm's Law, as follows:
[tex]V = IR\\I_{1}=I_{2}=I_{3}=\frac{V}{R} \\\\I_{1}=I_{2}=I_{3}=\frac{9\ Volt}{5 \Omega}\\\\[/tex]
I₁ = I₂ = I₃ = 12 A
how are characteristics of electromagnetic waves affected by medium
Hello,
QUESTION)Light is an electromagnetic wave, its speed is maximum in space and almost in the air where interactions have almost no effect. In other non-opaque media, light is subject to several phenomena: refraction and reflection. Part of the incident ray will be reflected in the same medium while the other part will be refracted in the new medium with a lower speed. In general, the medium influences the speed, and therefore the wavelength.
To teach you how to find the parameters characterizing an object in a circular orbit around a much heavier body like the earth.
The motivation for Isaac Newton to discover his laws of motion was to explain the properties of planetary orbits that were observed by Tycho Brahe and analyzed by Johannes Kepler. A good starting point for understanding this (as well as the speed of the space shuttle and the height of geostationary satellites) is the simplest orbit--a circular one. This problem concerns the properties of circular orbits for a satellite orbiting a planet of mass M. For all parts of this problem, where appropriate, use G for the universal gravitational constant.
1. Find an expression for the square of the orbital period.
2. The quantities v, K, U, and L all represent physical quantities characterizing the orbit that depend on radius R. Indicate the exponent (power) of the radial dependence of the absolute value of each.
Answer:
a) T² = ([tex]\frac{4\pi ^2}{GM}[/tex]) r³
b) veloicity the dependency is the inverse of the root of the distance
kinetic energy depends on the inverse of the distance
potential energy dependency is the inverse of distance
angular momentum depends directly on the root of the distance
Explanation:
1) for this exercise we will use Newton's second law
F = ma
in this case the acceleration is centripetal
a = v² / r
the linear and angular variable are related
v = w r
we substitute
a = w² r
force is the universal force of attraction
F = [tex]G \frac{m M}{r^2}[/tex]
we substitute
[tex]G \frac{m M}{r^2} = m w^2 r[/tex]
w² = [tex]\frac{GM}{r^3}[/tex]
angular velocity is related to frequency and period
w = 2π f = 2π / T
we substitute
[tex]( \frac{2\pi }{T} ) = \frac{GM}{r^3}[/tex]
the final equation is
T² = () r³
b) the speed of the orbit can be found
v = w r
v = [tex]\sqrt{\frac{GM}{r^3} } \ r[/tex]
v = [tex]\sqrt{\frac{GM}{r} }[/tex]
in this case the dependency is the inverse of the root of the distance
Kinetic energy
K = ½ M v²
K = ½ M GM / r
K = ½ GM² 1 / r
the kinetic energy depends on the inverse of the distance
Potential energy
U =
U = -G mM / r
dependency is the inverse of distance
Angular momentum
L = r x p
for a circular orbit
L = r p = r Mv
L =
L =
The angular momentum depends directly on the root of the distance
PLEASE HELP ME WITH THIS ONE QUESTION
Two substances of different temperatures are brought into thermal contact. While the objects come to equilibrium, some heat is lost to the environment. How would that affect the final temperature?
A) it would be higher
B) it would change unpredictably
C) it would remain the same
D) it would be lower
Answer:
the correct is D
Explanation:
In the calorimetry exercises, if there are no losses, we assume that all the heat lost by one body is absorbed by the other, but if there are losses
Q_ {yielded} = Q_ {absent} + Q_ {lost}
Since energy cannot be created or destroyed, they only ask to change, therefore the term of the absorbed heat must decrease, consequently the final temperature of the system is lower when there is loss of energy.
When checking the answers, the correct one is D
Which of the following is a conductor?
copper
water
aluminum
all of the above
Answer:
D all of the above
Explanation:
electricity moves easily through all of them and none of them prevent the flow of electricity
The microwaves produced inside a microwave have a wavelength of 12.0m and a frequency of 25Hz. At what speed do the microwaves travel in units of m/s ?
Answer: 300 m/s
Explanation:
The equation for finding wave speed is the wavelength times the frequency which would be
12.0mx 25hz=300m/s
given that two vectors A=i,2j-2k and B=6i+3j+2k find A +B
Answer:
7i, 5j, 0k
Explanation:
Add up the two vectors.
Add
i+i 1+6 = 7i
j+j 2+3 = 5j
k+k -2+2 = 0k
therefore A+B = (7i, 5j, 0k)
Chromosomes _____.
carry thousands of genes
can be analyzed in a karyotype
always occur in pairs
are tight coils of DNA
are carried on genes
Answer:
The correct answer for this would be D.
Explanation:
Are tight coils of DNA
What aquatic species is the least susceptible to acid rain? (Refer to the chart in the lesson to answer this question.)
a bass
b Baetis mayflies
c Bullfrogs
d Rainbow Trout
Answer:
c. Bullfrogs
Explanation:
I did this lesson and got it right! :)
Charging by Contact examples
Answer:
the hair and the comb are both neutral
Please please help I'm stuck!!!
Answer: iDc im in 3grade
Explanation:sorry
An electric motor supplies 2,500 Watts of power in a 220 V circuit. What is the resistance of the motor? Be sure to include the proper units in your answer. Remember... Ω is the unit for Resistance.
Answer:
R = 19.36 ohms
Explanation:
Given that,
The power of an electric motor, P = 2500 Watts
The voltage of the circuit, V = 220 V
We need to find the resistance of the motor. We can find it as follows :
[tex]P=\dfrac{V^2}{R}\\\\R=\dfrac{V^2}{P}\\\\R=\dfrac{(220)^2}{2500}\\R=19.36\ \Omega[/tex]
So, the resistance of the motor is 19.36 ohms.
A police car drives with a constant speed of 70km/hr. how long will it take to cover a distance of 135km?
(btw, it's a physics question:-)
Explanation:
36. How long does it take a car to slow down from a speed of 54 km/h to 32 km/h over a distance of 65 m? Answer in seconds. 37.
A uniform 140 g rod with length 57 cm rotates in a horizontal plane about a fixed, vertical, frictionless pin through its center. Two small 30 g beads are mounted on the rod such that they are able to slide without friction along its length. Initially the beads are held by catches at positions 11 cm on each sides of the center, at which time the system rotates at an angular speed of 23 rad/s. Suddenly, the catches are released and the small beads slide outward along the rod. Find the angular speed of the system at the instant the beads reach the ends of the rod. Answer in units of rad/s.
Answer:
The correct answer is "12 rad/s"
Explanation:
The given values are,
Mass of rod,
M = 140 g
i.e.,
= 0.14 kg
Length,
L = 57 cm
i.e.,
= 0.57 m
Mass of beads,
M = 30 g
i.e.,
= 0.03 kg
Angular speed,
r = 11 cm
i.e.,
= 0.11 m
Now,
The inertia of rods will be:
= [tex]\frac{1}{12}ML ^2[/tex]
On substituting the values, we get
= [tex]\frac{1}{12}\times 0.14\times (0.57)^2[/tex]
= [tex]0.0037905 \ kg-m^2[/tex]
The inertia of beads will be:
= [tex]mr^2[/tex]
On substituting the values, we get
= [tex]0.03\times (0.11)^2[/tex]
= [tex]0.000726 \ kg-m^2[/tex]
The total inertia will be:
= [tex]Inertia \ of \ rods+Inertia \ of \ beads[/tex]
= [tex]0.0037905 + 0.000726[/tex]
= [tex]0.0045165 \ kg-m^2[/tex]
now,
The angular speed of the system will be:
⇒ [tex]L_1w_1=L_2w_2[/tex]
On substituting the values in the above equation, we get
⇒ [tex]0.0045165\times 23 = (0.0037905 + (0.03\times 0.285^2)\times 2 )\times w_2[/tex]
⇒ [tex]0.1038795 = 0.0037905 + (0.00243675\times 2 )\times w_2[/tex]
⇒ [tex]w_2 = 12 \ rad/s[/tex]
Which types of reactions are also redox reactions?
Answer:
Your ans is B)
Explanation:
Hope its right
if wrong firgive me
help, it's an emergency !!!!!!!
Please help
The period of an oscillation is measured to be 0.0833 seconds. What is
the frequency of this oscillation? *
1.0833 Hz
0.287 Hz
9.8 Hz
12 Hz
0.007 Hz
Answer:
your
answer is
12.004
Two resistors R1 = 3 Ω and R2 = 6 Ω are connected in parallel. What is the net resistance in the circuit?
Answer:
2ohms
Explanation:
the net resistance is given by
1/R=1/R1 +1/R2,we are supposed to find R
thus by making R the subject ....
R=R1•R2/R1+R2
R=3•6/3+6
R=18/9 =2Ohms
Is there more than one way to get two objects with identical masses to balance? How?
Answer: yes you can
Explanation: because i i have a trying and a squar that have the same mass it would caunt as the same
Yes we can get two objects with identical masses to balance in this type of scenario.
What is Mass?
This is defined as the quantity of matter which is present in a body at a given point in time.
The two objects with identical masses can be made to balance through the use of a string and a pulley.
Read more about Mass here https://brainly.com/question/19385703
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Gaseous sulfur dioxide is a compound that combines with water in the atmosphere to form acid rain. What is the primary source of sulfur dioxide?
O volcanic emissions
O combustion of fossil fuels
O destruction of tropical forests
O mining and mineral extraction
How to calculate the voltage of a light bulb
Energy is radiated or transmitted in the form of rays or waves or particles.
B. radiation
C. convection
D. conduction
Answer:
B radiation
Explanation:
every type of transmitted waves are radioactive in a way.
PLEASE HELP ME WITH ONE QUESTION
If 1000 J of heat energy is lost from a piece of hot metal which is placed into a cup of cool water, how much energy is gained by the water?
Answer:
1000J
Explanation:
According to the law of calorimetry;
Heat lost by cold substance = Heat gained by hot substance
If 1000 J of heat energy is lost from a piece of hot metal,
heat lost by hot substance = 1000J
Since we are to determine how much energy is gained by the water, using the law
Heat lost by hot metal = heat gained by the water
Hence heat gained by the water = 1000J
A projectile is thrown with a velocity of 40 m/s, 45 degrees above the +x-axis. Determine its initial x-velocity and its initial y-velocity.
x-component is V·cos(angle)
y-component is V·sin(angle)
When the angle is 45°, its sin and cos are both 1/2·√2 .
Vx = 20·√2 = 28.28 m/s
Vy = 20·√2 = 28.28 m/s