Solution :
Given :
Weight = 4 lb
Stretched of a spring in equilibrium,Δ = 2 ft
a). We know that
F = kΔ
4 = k x 2
k = 2 lb/ft
∴ Stiffness of the spring is, k = 2 lb/ft
Motion is critically damped.
[tex]$\epsilon = 1$[/tex]
[tex]$\epsilon=\frac{C}{C_c} = 1$[/tex]
[tex]$C=C_c[/tex]
[tex]$C=C_c=\sqrt{4k_m}[/tex]
[tex]$C=\sqrt{4 \times 2 \times \left(\frac{4}{32.174}\right)}[/tex]
C = 0.99729 lb.s/ft.
b). Displacement
[tex]$y(t)=y_0 \sin (\omega t)$[/tex]
[tex]$\dot{y}(t)= y_0 \omega \cos (\omega t)$[/tex]
[tex]$[\dot{y}(t)]_{mon}= y_0 \omega $[/tex]
Initial displacement = 6 inches
[tex]$y_0 = 0.5 \ ft , \ \ \ \dot y (t) = 3 \ ft/sec$[/tex]
[tex]$\Rightarrow 3=0.5 \times \omega$[/tex]
[tex]$\Rightarrow \omega = 6$[/tex]
Therefore, displacement :
[tex]$y(t)=y_0 \sin (\omega t)$[/tex]
[tex]$y(t)=0.5 \sin (6 t)$[/tex]
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! :)
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
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
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]
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.
How to calculate the voltage of a light bulb
help, it's an emergency !!!!!!!
for the hypothetical salaries in the following
dataset, what is the average salary per year?
Data set of hypothetical salaries: $46,000 per year,
$20,000 per year, $33,000 per year, $27,000 per year,
$91,000 per year.
Answer: $43400 per year
Explanation:
The Data set of hypothetical salaries is given as:
$46,000 per year,
$20,000 per year,
$33,000 per year,
$27,000 per year,
$91,000 per year.
The average salary per year will be the addition of the salaries per year above which will then be divided by 5. This will be:
= ($46,000 + $20,000 + $33,000 + $27,000 + $91,000) / 5
= $217000/5
= $43400 per year
The average salary per year will be $43400
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
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:
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
Charging by Contact examples
Answer:
the hair and the comb are both neutral
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
who compose the Ghana national anthem
Answer:
Philip Gbeho
Explanation:
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
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.
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
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
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
Suppose that 2 J of work is needed to stretch a spring from its natural length of 24 cm to a length of 42 cm. (a) How much work is needed to stretch the spring from 32 cm to 34 cm
Answer:
Workdone = 0.025 Joules
Explanation:
Given the following data;
Workdone = 2J
Extension = 42 - 24 = 18 cm to meters = 18/100 = 0.18m
The workdone to stretch a string is given by the formula;
Workdone = ½ke²
Where;
k is the constant of elasticity.
e is the extension of the string.
We would solve for string constant, k;
2 = ½*k*0.18²
2 = ½*k*0.0324
Cross-multiplying, we have;
4 = 0.0324k
k = 4/0.0324
k = 123.46 N/m
a. To find the workdone when e = 32, 34.
Extension = 34 - 32 = 2 to meters = 2/100 = 0.02m
Workdone = ½*123.46*0.02²
Workdone = 61.73 * 0.0004
Workdone = 0.025 Joules
Therefore, the amount of work (in J) needed to stretch the spring from 32 cm to 34 cm is 0.67.
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
Which types of reactions are also redox reactions?
Answer:
Your ans is B)
Explanation:
Hope its right
if wrong firgive me
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:
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)
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
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.
Please please help I'm stuck!!!
Answer: iDc im in 3grade
Explanation:sorry
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
#SPJ9
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.
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