Answer:
Below
Explanation: 1.Katie likes to read and would rather do that than play sports. Her friends make fun of her and tell her that reading is for nerds. Katie stops reading so much and starts to play sports more.
2. Marcus wants to go to a small community college close to home, but most of the kids in his class are applying to larger colleges out of state. Marcus decides that he should also apply to those colleges.
A fish finder uses a sonar device that sends 20,000-Hz sound pulses downward from the bottom of the boat, and then detects echoes. If the maximum depth for which it is designed to work is 85 m, what is the minimum time between pulses (in fresh water)?
Answer:
0.3106 seconds
Explanation:
Frequency= 20,000-Hz
The speed of echoes sounds can be calculated using the expression below;
Y= ( 2x/t) ...........................eqn(1)
t= overall time taken
x = maximum depth = 230m
Y= speed of echoes sounds
Speed of sound in water= 1,481 m/s which is a constant with little variation.
If we substitute the given values into eqn(1) we have
1481 = (2× 230)/ t
1481 × t= 460
t=460/1481
t=0.3106 seconds
Hence, the minimum time between pulses (in fresh water) is 0.3106 seconds
An unstrained horizontal spring has a length of 0.29 m and a spring constant of 180 N/m. Two small charged objects are attached to this spring, one at each end. The charges on the objects have equal magnitudes. Because of these charges, the spring stretches by 0.021 m relative to its unstrained length. Determine (a) the possible algebraic signs and (b) the magnitude of the charges.
Answer:
A) they both have the same algebraic sign
B)6.377×10^-6 C
Explanation:
From columb's law, the force acting on both charges can be expressed as
F=( kq1*q2)/r^2
Where F= electrostatic force
r= distance between the charges
q1 and q2= charges
The force acting on a spring can be expressed as
F= kx..................eqn(2)
Where
K= spring constant = 180 N/m.
x= stretch of the string= 0.021m
Substitute the values into eqn (2)
F= (180×0.021)
F= 3.78N
If we compare with spring force,
Hence, F( electrostatic) = 3.78N
From
F=( kq1*q2)/r^2 ..............eqn(1)
Where
r= (0.29 m + 0.021m)= 0.311m
K= the electrostatic constant= 8.99×10^9 kg⋅m3⋅s−2⋅C−2.
If we substitute the values we have
Since the charges are the same, then
kq1 and q2 equals "q"
3.78= (8.99×10^9 ×q^2)/(0.311)^2
Making q^2 subject of the formula
3.78× (0.311)^2 = 8.99×10^9 × q^2
q^2= [(0.311)^2 × 3.78]/8.99×10^9
q^2= 40.668×10^-12
q=√40.668×10^-12
q= 6.377×10^-6 C
(a) the possible algebraic signs
They have the same algebraic sign
(b) the magnitude of the charges.
6.377×10^-6 C
A car is traveling on a straight road at a constant 35 m/sm/s, which is faster than the speed limit. Just as the car passes a police motorcycle that is stopped at the side of the road, the motorcycle accelerates forward in pursuit. The motorcycle passes the car 13.5 ss after starting from rest. What is the acceleration of the motorcycle (assumed to be constant)
Answer:
2.59m/s
Explanation:
Using the equation of motion
v = u+at
v is the final velocity = 35ms
u is the initially velocity = 9m/s
t is the time = 13.5s
a is the acceleration
Substitute into the formula
35 = 0+13.5a
a = 35/13.5
a = 2.59m/s²
Hence the acceleration of the motorcycle is 2.59m/s
When testing a home for radon, where is the most likely place for the highest detected level? A) the basement, due to ground seepage B) the first floor, due to doors to the outside allowing radon to enter C) the second floor, due to the chimney effect D) all areas will have equal levels of radon E) radon cannot be tested because it is odorless, colorless, and tasteless
Answer:
A
Explanation:
ive been buying loui i been shoppin
Answer: E) radon cannot be tested because it is odorless, colorless, and tasteless
Explanation:
edge2021
Using equations, determine the temperature, pressure and density of the air for a aircraft flying at 19.5 km. Is this aircraft subsonic or supersonic
Answer:
a) - 72.5°c
b) pressure = 3625.13 Pa
c) density = 0.063 kg/m^3
d) it is a subsonic aircraft
Explanation:
a) Determine Temperature
Temperature at 19.5 km ( 19500 m )
T = -131 + ( 0.003 * altitude in meters )
= -131 + ( 0.003 * 19500 ) = - 72.5°c
b) Determine pressure and density at 19.5 km altitude
Given :
Po (atmospheric pressure at sea level ) = 101kpa
R ( gas constant of air ) = 0.287 KJ/Kgk
T = -72.5°c ≈ 200.5 k
pressure = 3625.13 Pa
hence density = 0.063 kg/m^3
attached below is the remaining part of the solution
C) determine if the aircraft is subsonic or super sonic
Velocity ( v ) = [tex]\sqrt{CRT}[/tex] = [tex]\sqrt{1.4*287*200.5 }[/tex] = 283.8 m/s
hence it is a subsonic aircraft
Sandy is riding a bicycle with tires that have a diameter of 650 mm. A small twig, caught in the spokes, causes the tire to click once each revolution. Of Sandy hears 8 such clicks every 3 seconds then how fast is she cycling (to the nearest km/hr)
Answer:
Explanation:
Sandy hears 8 such clicks every 3 seconds and a small twig, caught in the spokes, causes the tire to click once each revolution that means the wheel of the cycle is rotating at 8 rotations every 3 seconds or 8/3 rotation per second . In each rotation , it moves distance equal to its circumference .
circumference = 2π r = 2 x 3.14 x .65 / 2 m
= 2.041 m
In 8/3 rotation , distance covered = 8/3 x 2.041 = 5.44 m
So speed of cycle is 5.44 m per second
5.44 x 60 x 60 m per hour
19584 m per hour
= 19.584 km per hour .
= 20 km per hour approx.
Charlotte is driving at 66.5 mi/h and receives a text message. She looks down at her phone and takes her eyes off the road for 3.47 s. How far has Charlotte traveled in feet during this time
Answer:
the distance traveled by Charlotte in feet is 338.44 ft
Explanation:
Given;
speed of Charlotte, u = 66.5 mi/h
time of motion, t = 3.47 s
The distance traveled by Charlotte in feet is calculated as;
[tex]Distance = Speed \ \times \ time \\\\D = ut\\\\D = (\frac{66.5 \ mi}{h} \times \frac{5280 \ ft}{1 \ mi} \times \frac{1 \ h}{3600 \ s} )(3.47 \ s)\\\\D = 338.44 \ ft[/tex]
Therefore, the distance traveled by Charlotte in feet is 338.44 ft
please help asap!!
Explain the movement of a roller coaster in terms of potential and kinetic energy? When are these energies thegreatest? Smallest? Are they ever the same?
Answer:
Potential energy: Greatest at the top of the hill
Kinetic energy: Greatest at the bottom of the hill
The two meet at some point on the way down!
Explanation:
Potential energy is energy that represents an object's potential for motion. Kinetic energy is that object's energy during motion. They're two sides of the same coin, and in fact, their sum gets a special name: mechanical energy. Potential energy builds up in reaction to working against certain forces - in the case of the roller coaster, that primary force is gravity. Gravity exerts a downward force on the roller coaster, and it takes work to pull it up the hill.
When it reaches the peak, the coasters potential energy is at its highest, and the moment it crests over the hill and begins its descent, that gravitational potential energy starts converting into kinetic energy: the coaster starts accelarating down the track, and the potential energy decreases at the same rate that the kinetic energy increases.
At the bottom of the hill, all of that potential energy has become kinetic energy, and the coaster zooms along the track, hopefully not giving too many riders nausea
2. Which of the following items would be the WORST conductor of electricity?
A. A steel rod
B. A copper wire
C. An aluminum bat
D. A rubber band
Answer: a rubber band
Explanation: A rubber band has no conductivity and no electricity would be able to flow whereas steel and copper and aluminum would be able to allow electricity to flow due to how they are built
The tub of a washer goes into its spin-dry cycle, starting from rest and reaching an angular speed of 4.0 rev/s in 9.0 s. At this point, the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub slows to rest in 15.0 s. Through how many revolutions does the tub turn during this 24 s interval
Answer:
48 rev
Explanation:
a) we can calculate the distance covered by the tube using the formula:
θ = (ω + ωo)t/2
where ω is the final angular speed, θ is the distance covered, t is the time taken, ωo is the initial angular speed.
Firstly, we calculate the distance covered from 0 to 9 s then from 9s to 24 s.
within 9s, the tub runs from rest (0) to 4 rev/s, hence:
t = 9s, wo = 0, w = 4 rev/s = (4 * 2π) rad/s = 8π rad/s. Hence:
θ = (ω + ωo)t/2 = (0 + 8π)9 / 2 = 36π rad
θ = 36π rad = (36π)/2π rev = 18 rev
Also, within 15 s, the tub runs from 4 rev/s to rest, hence:
t = 15 s, wo = 4 rev/s = 8π rad/s, w = 0 rad/s. Hence:
θ = (ω + ωo)t/2 = (8π + 0)15 / 2 = 60π rad
θ = 60π rad = (60π)/2π rev = 30 rev
Therefore the total revolutions by the tube during 24 s interval = 30 rev + 18 rev = 48 rev
Two 90.0-kilogram people are separated by 3.00 meters. What is the magnitude of the gravitational force that one person exerts on the other?
Answer:
the magnitude of gravitational force is 6 x 10⁻⁸ N.
Explanation:
Given;
mass of the two people, m₁ and m₂ = 90 kg
distance between them, r = 3.0 m
The magnitude of gravitational force exerted by one person on another is calculated as;
[tex]F = \frac{Gm_1m_2}{r^2} \\\\[/tex]
where;
G is gravitational constant = 6.67 x 10⁻¹¹ Nm²/kg²
[tex]F = \frac{Gm_1m_2}{r^2} \\\\F = \frac{6.67\times 10^{-11} \times \ 90 \ \times \ 90}{3^2} \\\\F = 6\times 10^{-8} \ N[/tex]
Therefore, the magnitude of gravitational force is 6 x 10⁻⁸ N.
Followed by the previous question: presume that the electron performs a uniform circular motion around the hydrogen nucleus. What is the magnitude of the centripetal acceleration in m/sec2? (radius of the circle LaTeX: 5\times 10^{-11}5 × 10 − 11m; period of the motion LaTeX: 1.5 \times 10^{-16}1.5 × 10 − 16sec) Group of answer choices
Answer:
[tex]A_c=87.73*10^{21}m/s[/tex]
Explanation:
From the question we are told that
[tex]r=5\times 10^{-11}[/tex]
[tex]T=1.5 \times 10^{-16}[/tex]
Generally the equation for velocity is mathematically given as
[tex]Velocity (v)=\frac{2 \pi r}{t}[/tex]
[tex]V=\frac{2 \pi (5*10^{-11})}{1.5*10^{-16}}[/tex]
[tex]V=\frac{2 \pi (5*10^{-11})}{1.5*10^{-16}}[/tex]
Generally the equation for Centripetal acceleration is mathematically given as
[tex]A_c=\frac{V^2}{r}[/tex]
[tex]A_c=(\frac{20.944*10^5)}{r5*10^{-11}}[/tex]
[tex]A_c=87.73*10^{21}m/s[/tex]
a block of mas \( m \) = 4.8 kg slides head on into a spring of spring constant \( k \) = 430 N/m. When the block stops, it has compressed the spring by 5.8 cm. The coefficient of kinetic friction between block and floor is 0.28. \( (g =9.8m/s^2) \)
Answer:
See explanation below
Explanation:
The question is incomplete. The missing part of this question is the following:
"While the block is in contact with the spring and being brought to rest, what are (a)the work done by the spring force and (b) the increase in thermal energy of the blockfloor system? (c) What is the blocks speed just as it reaches the spring?"
According to this we need to calculate three values: Work, Thermal Energy and Speed of the block when it reaches the spring.
Let's do this by parts.
a) Work done by the spring:
In this case, we need to apply the following expression:
W = -1/2 kx² (1)
We know that k = 430 N/m, and x is the distance of compressed spring which is 5.8 cm (or 0.058 m). Replacing that into the expression:
W = -1/2 * 430 * (0.058)²
W = -0.7233 Jb) Increase in thermal energy
In this case we need to use the following expression:
ΔEt = Fk * x (2)
And Fk is the force of the kinetic energy which is:
Fk = μk * N (3)
Where μk is the coeffient of kinetic friction
N is the normal force which is the same as the weight, so:
N = mg (4)
Let's calculate first the Normal force (4), then Fk (3) and finally the chance in the thermal energy (2):
N = 4.8 * 9.8 = 47.04 N
Fk = 0.28 * 47.04 = 13.1712 N
Finally the Thermal energy:
ΔEt = 13.1712 * 0.058
ΔEt = 0.7639 Jc) Block's speed reaching the spring
As the block is just reaching the speed, the initial Work is 0. And the following expression will help us to get the speed:
V = √2Ki/m (5)
And Ki, which is the initial kinetic energy can be calculated with:
Ki = ΔU + ΔEt (6)
And ΔU is the same value of work calculated in part (a) but instead of being negative, it will be positive here. So replacing the data first in (6) and then in (5), we can calculate the speed:
Ki = 0.7233 + 0.7639 = 1.4872 J
Finally the speed:
V = √(2 * 1.4872) / 4.8
V = 0.7872 m/sHope this helps
Consider a Carnot cycle executed in a closed system with 0.6 kg of air. The temperature limits of the cycle are 300 and 1100 K, and the minimum and maximum pressures that occur during the cycle are 20 and 3000 kPa. Assuming constant specific heats, determine the net work output per cycle.
Answer:
63.8 kJ
Explanation:
The net work output per cycle is the difference in heat input and heat output. The heat input and heat output are expressed as a function of volume ratios, while volume is expressed as a function of pressure and pressure as a function of temperature.
R = 287 J/kg.K, k = 1.4
Hence the net work input (W) is given as:
[tex]W=Q_{in}-Q_{out}\\\\W=mR[T_Hln\frac{V_2}{V_1} -T_Lln\frac{V_3}{V_4}]\\\\=mR[T_Hln\frac{P_1}{P_2} -T_Lln\frac{P_4}{P_3}]\\\\=mR[T_Hln(\frac{P_1}{P_3}(\frac{T_L}{T_H} )^\frac{k}{k-1}) -T_Lln(\frac{P_1}{P_3}(\frac{T_L}{T_H} )^\frac{k}{k-1})]\\\\=mR(T_H-T_L)ln(\frac{P_1}{P_3}(\frac{T_L}{T_H} )^\frac{k}{k-1})\\\\Substituting\ values:\\\\W=mR(T_H-T_L)ln(\frac{P_1}{P_3}(\frac{T_L}{T_H} )^\frac{k}{k-1})=0.6*287(1100-300)ln(\frac{3000*10^3}{2-*10^3}(\frac{300}{1100} )^\frac{1.4}{1.4-1})\\\\[/tex]
[tex]W=63.8\ kJ[/tex]
what changes when unbalanced forces are applied to a moving bike along the direction its moving?
A. inertia
B.friction
C. mass
D.velocity
Answer:
D.velocity
Explanation:
When unbalanced forces are applied to a moving bike along the direction its moving, the velocity of the bike changes.
Unbalanced forces causes a body to accelerate. Acceleration is the rate of change of velocity with time.
When unbalanced forces acts on a body, the velocity changes.
An unbalanced force is a force whose resultant is not zero. Such a force causes a body to change motion and then acceleration. For a body to accelerate, the velocity must change per unit of time.What three factors affect the viscosity of magma
The factors that affect the viscosity of magma include temperature, crystal and rock fragments (composition), and the different dissolved gases.
What is magma?It is a mixture of solid, volatile and liquid materials.
Characteristics of the viscosity of magmaIt is a mixture of chemical components that form high-temperature silicates.It includes substance in solid, liquid and gaseous state due to the temperature of the magma which is above the melting points of certain components.Volcanic eruptions often occur when the vapor pressure of the gases becomes greater than the pressure exerted by the solid rocks that keep the magma confined.Therefore, we can conclude that the fluidity or viscosity of magma depends on its chemical composition and, in particular, the liquids and solids that the magma contains and the various gases dissolved in it.
Learn more about viscosity of magma here: https://brainly.com/question/20621986
The moon has a gravitational field strength (acceleration due to gravity) that is about 1/6 that of
Earth's. What is the gravitational field strength (acceleration due to gravity) on the moon?
Answer:
The gravitational field strength (acceleration due to gravity) on the moon is 1.63 m/s²
Explanation:
From the question, the moon has a gravitational field strength (acceleration due to gravity) that is about 1/6 that of Earth's.
To determine the gravitational field strength (acceleration due to gravity) on the moon, we will multiply the Earth's gravitational field strength (acceleration due to gravity) by 1/6.
Earth's gravitational field strength = 9.8 m/s²
∴ Moon's gravitational field strength = 1/6 × 9.8 m/s²
Moon's gravitational field strength = 1.63 m/s²
Hence, the gravitational field strength (acceleration due to gravity) on the moon is 1.63 m/s².
What is the difference between a wave and energy?
Answer:
The higher the amplitude, the higher the energy. To summarise, waves carry energy. The amount of energy they carry is related to their frequency and their amplitude. The higher the frequency, the more energy, and the higher the amplitude, the more energy
Explanation:
The main difference between a wave and energy is: wave is oscillation of energy whereas energy is ability of doing work.
What is wave?A wave is an energetic disturbance in a medium that doesn't include any net particle motion. Elastic deformation, a change in pressure, an electric or magnetic intensity, an electric potential, or a change in temperature are a few examples.
What is energy?The capacity to do work is energy. Energy can only be changed from one form to another; it cannot be created or destroyed. Energy is measured in Joules, the same unit used to measure work. There are several sorts of energy since it is present in many different things.
There are two types of energy: kinetic and potential. Kinetic energy is the energy that is in motion, whereas potential energy is the energy that is stored in an object and is determined by the amount of work that is required.
Learn more about energy here:
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Tim has a weight of 500N, which his half of his father's
weight. He, his father and his uncle sit on a see saw. If
both Tim and his father sit on the right ended of the
see saw, 5m from the pivot, his uncle's weight is the
same his fathers. Where should Tim's uncle sit in order
to achieve a state of balance?
Answer:
3.75m on the left end
Explanation:
Given data
Tim's weight = 500N= 0.5kN
Tim's fathers weight= 500*2= 1000N= 1kN
Tim and the fathers weight = 500+1000= 1500N= 1.5kN
Tim's uncle weight= 1.5kN
Length of seesaw= 5m
let the distance Tim's uncle sits be x
We know that summation of clockwise moment equals the summation of anticlockwise moment
Taking moment about the center of the seesaw
1.5*2.5= 1*x
3.75= 1x
Divide boths sides by 1
x= 3.75/1
x= 3.75m
Hence Tim's uncle will sit 3.75m on the left end
Complete the following statement: Momentum will be conserved in a two-body collision only if a both bodies come to rest. b the internal forces of the two body system cancel in action-reaction pairs. c the kinetic energy of the system is conserved. d the net external force acting on the two-body system is zero. e the collision is perfectly elastic.
Answer:
d the net external force acting on the two-body system is zero
Explanation:
The net external force acting on the two-body system is zero .
During a collision , two internal forces appear on two bodies in opposite directions separately . As they act on each object separately , they do not cancel each other . But the net force on two body system is zero . Total momentum is always conserved during collision because no external force is involved . Collision is not always elastic .
Energy Eating a banana enables a monkey to perform 4,000 J of work. How high would this enable a 15 kg monkey to climb? W = F.d F=MYA (Earth's Gravity)
Answer:
27.2m approx
Explanation:
Given data
Work done= 4000J
mass= 15kg
W= mg
W= 15*9.81
W= 147.15N
We know that
Work done= W*d
substitute
4000=147.15*d
divide both sides by 147.15
d= 4000/147.15
d=27.18
Hence the distance is 27.2m approx
A gas is enclosed in a cylinder fitted with a light frictionless piston and maintained at atmospheric pressure. When 1400 kcal of heat is added to the gas, the volume is observed to increase slowly from 12.0 m3 to 19.9 m3.
a) Calculate the work done by the gas.
I found this to be 7.4 * 10^5 J
b) Calculate the change in internal energy of the gas
____ J
Answer:
(a) The work done by the gas 8.005 x 10⁵ J
(b) the change in internal energy is 5.0575 x 10⁶ J
Explanation:
Given;
heat added to the gas, Q = 1400 kcal = 1400 kcal x 4184 J/kcal = 5.858 x 10⁶ J.
change in volume, ΔV = 19.9 m³ - 12.0 m³ = 7.9 m³
atmospheric pressure, P = 101325 N/m²
(a) The work done by the gas = PΔV
= 101325 x 7.9
= 8.005 x 10⁵ J
(b) the change in internal energy is obtained from first law of thermodynamic;
ΔU = Q - W
ΔU = 5.858 x 10⁶ J - 8.005 x 10⁵ J
ΔU = 58.58 x 10⁵J - 8.005 x 10⁵ J
ΔU = 5.0575 x 10⁶ J
A disk is rotating with an angular velocity function given by ω=Kt+L. What is the angular acceleration of the disk at t=T ?
Answer:
Angular acceleration of the disk ∝ = K
Explanation:
Given that;
Angular velocity function given by ω = Kt + L
Angular acceleration of the disk at t=T is = ?
Now,
Angular velocity;
ω = Kt + L
Angular acceleration is;
∝ = dω / dt
= [tex]\frac{d}{dt}[/tex] ( Kt + L )
At t = T
∝ = K
Because ∝ is not dependent on t
Therefore
Angular acceleration of the disk ∝ = K
1. Given an element's atomic number and mass number, how can you tell the number of protons and neutrons in its nucleus?
Number of protons = mass number; number of neutrons atomic number - mass number
Number of protons = atomic number; number of neutrons = mass number + atomic number
Number of protons = atomic number; number of neutrons = mass number - atomic number
Answer:
last one. c
Explanation:
atomic number; number of neutrons = mass number - atomic number is the very important to find the number of the question.
Define the physics quantity of work
Explanation:
Work done is the force applied to move a body through a specific or particular direction.
It is also the difference in the amount of energy expended in using an effort.
Work done is given as;
Work done = F x d CosФ
F is the force applied
d is the displacement
Ф is the angle
The unit of work done is in Joules.
what is the direction of the third force that would cause the box to remain stationary on the ramp ?
An arrow pointing from the bottom of the ramp to the top, I assume it would be friction.
A ratio is another name for a decimal true or false
Which of the following is NOT a step used to perform a scientific inquiry
Answer:
b. Designing an uncontrolled experiment.
Explanation:
They always have it controlled.
Answer:
B. Designing an uncontrolled experiment.
Explanation:
Correct Answer!!!!!!
The number of employees for a certain company has been decreasing each year by 4%. If the company currently has 650 employees and this rate continues, find
the number of employees in 20 years.
The number of employees in 20 years will be approximately
(Round to the nearest whole number as needed)
HELP PLEASE!
Three people pull simultaneously on a stubborn donkey. Jack pulls eastward with a force of 83.5 N, Jill pulls with 93.3 N in the northeast direction, and Jane pulls to the southeast with 121 N. (Since the donkey is involved with such uncoordinated people, who can blame it for being stubborn
Answer:
235.8 N
Explanation:
Given that
Jack
83.5 east
Jill
93.3√2/2 east
93.3√2/2 north
Jane
121√2/2 east
121√2/2 south
From the above listed, we can calculate the total force component on x axis to be
Fx = 83.5 + 93.3√2/2 + 121√2/2
Fx = 83.5 + 65.97 + 85.56
Fx = 235 N (east)
Again, we calculate the total force component on y axis to be
Fy = 93.3√2/2 - 121√2/2
Fy = 65.97 - 85.56
Fy = -19.59 N (south)
Finding the resultant, we have
F = √(Fx²+Fy²)
F = √(235² + (-19.59)²)
F = √55225 + 383.7681
F = √55608.7681
F = 235.8 N