The length of the immersed part of the wood is 0.2m.
What is density?The density is the ratio of the mass and the volume of the object. It is denoted by ρ.
ρ = mass/Volume = m/V
Volume = Area of cross-section A x height h
Given is a piece of wood of mass 40g =0.04kg and uniform cross-sectional area A= 2cm² =2x10⁻⁴ m² floats upright in water.
The density of water ,ρ = 1000 kg/m³
The density related to length of part immersed is
1000 = 0.04/ (2x10⁻⁴ x h)
h = 0.2m
Thus, the length of the immersed part of the wood is 0.2m.
Learn more about density.
https://brainly.com/question/9215083
#SPJ1
The mass of a bicyclist and a bicycle together is 53.0 kg. How much work has been
done if the bicyclist slows the bicycle from a speed of 3.84 m/s to 1.27 m/s?
(A) -68.1 J
(B) -136 J
(C) -348 J
(D) -696 J
Answer:
Approximately [tex](-348\; {\rm J})[/tex], assuming that the bike was on level ground.
Explanation:
If an object of mass [tex]m[/tex] is moving at a speed of [tex]v[/tex], the kinetic energy of that object would be [tex](1/2)\, m\, v^{2}[/tex].
At a speed of [tex]v = 3.84\; {\rm m\cdot s^{-1}}[/tex], the kinetic energy of the bike and the cyclist- combined- would be:
[tex]\begin{aligned} &\frac{1}{2}\, m\, v^{2} \\=\; &\frac{1}{2}\times 53.0\; {\rm kg} \times (3.84\; {\rm m\cdot s^{-2}})^{2} \\ \approx \; & 390.76\; {\rm J}\end{aligned}[/tex].
At a speed of [tex]v = 1.27\; {\rm m\cdot s^{-1}}[/tex], the kinetic energy of the bike and the cyclist- combined- would be:
[tex]\begin{aligned} &\frac{1}{2}\, m\, v^{2} \\=\; &\frac{1}{2}\times 53.0\; {\rm kg} \times (1.27\; {\rm m\cdot s^{-2}})^{2} \\ \approx \; &42.741 \; {\rm J}\end{aligned}[/tex].
The energy change was approximately:
[tex]390.76\; {\rm J} - 42.741\; {\rm J} \approx 348\; {\rm J}[/tex].
If the bike was on level ground, the friction on the bike and the cyclist would have done a work of [tex](-348\: {\rm J})[/tex] to reduce the kinetic energy of the bike and the cyclist by that amount.
Answer: C) -348J
Explanation:
42.741 - 390.76 (the kinetic energy of the two speeds) is equal to -348.
A brick is kept in 2 different ways on a table as shown
below. which brick exerts more pressure? Why?
Answer:
A
Explanation:
when area increases pressure decrease
for example, a sharp nail's area is lower than a blunt nail, so sharp nail is easy to fix
so, here a exerts more pressure
Answer:
a
Explanation:
Pls answer, i need help :(
Answer: B
Explanation: AN increase in heat out
You suspect that the power supply in your desktop pc is failing. you want to use a multimeter to test the power supply. which multimeter setting should you use
The multimeter setting should you use is between 11-12 volts. If the voltage is too high or too low, the power supply must be changed.
What is a multimeter?An instrument made to measure resistance, voltage, and electric current, often across a range of values.
You think your desktop computer's power supply is malfunctioning. To test the power supply, you should use a multimeter.
Between 11 and 12 volts should be seen on the multimeter. The power supply is failing and has to be replaced if it's too high or too low.
Hence, the multimeter setting should you use is between 11-12 volts.
To learn more about the multimeter refer:
https://brainly.com/question/5135212
#SPJ1
Which property of sound waves decreases as the square of the distance from the source increases? A. Pitch
B. Intensity C. Wavelength D. Speed
Intensity is the property of sound waves that decreases as the square of the distance from the source increases. Option B is correct.
What is a sound wave?A sound wave is produced when a medium begins to vibrate. When an entity vibrates, a pressure wave is formed, which causes sound.
As the square of the distance from the source increases, the intensity of sound waves decreases.
Sound intensity relationship
[tex]\rm {I} = \frac{1}{r^2}[/tex]
[tex]\rm \frac{I_2}{I_1} =\frac{r_1^2}{r_1^2}[/tex]
Hence, option B is correct.
To learn more about the sound wave, refer to
https://brainly.com/question/11797560.
#SPJ1
A 950-kg car strikes a huge spring at a speed of 22m/s (fig. 11-54), compressing the spring 5.0m. (a) what is the spring stiffness constant of the spring? (b) how long is the car in contact with the spring before it bounces off in the opposite direction?
(a) The spring stiffness constant of the spring is 18,392 N/m.
(b) The time the car was in contact with the spring before it bounces off in the opposite direction is 0.23 s.
Kinetic energy of the carThe kinetic energy of the car is calculated as follows;
K.E = ¹/₂mv²
K.E = ¹/₂ x 950 x 22²
K.E = 229,900 J
Stiffness constant of the springThe stiffness constant of the spring is calculated as follows;
K.E = U = ¹/₂kx²
k = 2U/x²
k = (2 x 229,900)/(5)²
k = 18,392 N/m
Force exerted on the springF = kx
F = 18,392 x 5
F = 91,960 N
Time of impactF = mv/t
t = mv/F
t = (950 x 22)/(91960)
t = 0.23 s
Learn more about spring constant here: https://brainly.com/question/1968517
#SPJ4
Which of the following energies is related to temperature change
Thermal energy is a type of energy that is related to temperature change. Details about thermal energy can be found below.
What is thermal energy?Thermal energy refers to the internal energy of a system in thermodynamic equilibrium due to its temperature.
Thermal energy of a body is determined by the difference in temperature in the surrounding environment and the body.
Therefore, thermal energy is a type of energy that is related to temperature change.
Learn more about thermal energy at: https://brainly.com/question/11278589
#SPJ1
Where are heavier elements, like iron or gold made?
*
1 point
In space, between the stars
in the black holes at the centers of galaxies
In the hearts of stars
They were made as part of the big bang
Answer:
In the hearts of stars:
Theory tells us the elements heavier than iron are created by novas
that is when a star explodes, and any heavier elements were once created when a star exploded.
Some iron has a coefficient of linear expansion of 12 x 10-6 / o K . A 100 mm length of iron piping is heated through 20 K. The pipe extends by:
Given that the linear expansion of the pipe is 12×10¯⁶ K¯¹, the pipe extends by 0.024 mm
Data obtained from the question Original length (L₁) = 100 mmChange in temperature (ΔT) = 20 KCoefficient of expansion (α) = 12×10¯⁶ K¯¹Change in length (ΔL) =?How to determine the new diameter
α = ΔL / L₁ΔT
12×10¯⁶ = ΔL / (100 × 20)
12×10¯⁶ = ΔL / 2000
Cross multiply
ΔL = 12×10¯⁶ × 2000
ΔL = 0.024 mm
Learn more about linear expansion:
https://brainly.com/question/23207743
#SPJ1
Which form of energy is converted to electrical energy in a voltaic cell?.
Answer:
chemical energy is converted to electrical energy in a voltaic cell.
Rearrange the equation = KE
-1
2
- my? to solve for v. Show your work.
Answer:
See below
Explanation:
KE = 1/2 m v^2 multiply both sides by 2
2 (KE) = mv^2 divide both sides by m
2(KE) / m = v^2 sqrt both sides
√ [(2KE)/m ] = v
A race car sits at the starting line on a racetrack. When the race starts, the car's tires exert a force on the track. According to Newton's third law of motion, WHAT PREVENTS THE RACE CAR FROM SINKING INTO THE TRACK?
A. The force of friction between the car tires and the track prevents the car from moving.
B. The track surface exerts a force that is larger and in the same direction as the force exerted by the tires.
C. A normal force that is equal in magnitude and opposite in direction to gravity pushes on the car.
D. The track exerts a force that is equal and in the opposite direction as the force exerted by the tires.
To prevent the race car from sinking into the track, the track exerts a force that is equal and in the opposite direction as the force exerted by the tires.
What is Newton's third law of motion?
Newton's third law of motion states that force every action there is equal and opposite reaction.
That is the force exerted on an object is equal in magnitude to the reaction of the object.
Fa = - Fb
According to this law, Fa is equal to Fb in magnitude but the directions are different.
Thus, to prevent the race car from sinking into the track, the track exerts a force that is equal and in the opposite direction as the force exerted by the tires.
Learn more about Newton's third law of motion here: https://brainly.com/question/62770
#SPJ1
Which option is an example of an object that has potential energy followed by an object that has kinetic energy?
A ball held over a person's head | a ball rolling on the floor is an example of an object that has potential energy followed by an object that has kinetic energy.
What is Kinetic energy?This is the type of energy possessed by a body by virtue of its motion or movement.
The rolling ball therefore has kinetic energy while a ball being held over a person's head has potential energy which is the energy possessed by a body by virtue of its position.
Read more about Kinetic energy here https://brainly.com/question/8101588
#SPJ1
A massless rod is attached to the ceiling by a string. Two weights are hung from the rod: a 0.4-lb weight at its left end and a 1.2-lb weight at its right end. The length of the rod is L and a string is attached (3L/4 from its left end) so that the rod (with attached weights) is horizontal. What is the tension in the string supporting the rod and the attached weights
The tension in the string supporting the rod and the attached weights is 7.11 N.
Tension in the string supporting the rodThe tension in the string supporting the rod and the attached weights is the sum of the weights supported by the strings.
T = (m1 + m2)g
where;
m1 and m2 are the two masses supported0.4lb + 1.2lb = 1.6lb = 0.725 kg
T = 0.725 x 9.8
T = 7.11 N
Learn more about tension here: https://brainly.com/question/918617
#SPJ1
A 1050 w electric toaster operates on a household circuit of 120 v. what is the resistance of the wire that makes up the heating element of the toaster
The Resistance of the wire that makes up the heating element of the toaster is 13.75Ω.
What is Resistance?
Resistance is the measure of the opposition to current flow in an electrical circuit.
S.I. Unit of resistance is ohms, symbolized by the Greek letter omega (Ω)
Also from Ohm's Law,[tex]R=\frac{V}{I}[/tex]
From power-current relation
P=VI
Also, [tex]I=\frac{P}{V}[/tex]
[tex]I = \frac{1050}{120}[/tex]
I = 8.75 A
From Ohm's Law,[tex]R=\frac{V}{I}[/tex]
[tex]R = \frac{120}{8.75}[/tex]
R = 13.75 Ω
The Resistance of the wire is 13.75 Ω
For more resistance questions visit
https://brainly.com/question/14547003
#SPJ1
G= 10m/s
A 50kg student jumps out of a window onto a pile of mattresses.
(a) Ignoring air resistance, what is her increase in speed each second?
B) What is her change of momentum each second?
The increase in velocity of the student per second is 10 m/s^2 and her change in momentum each second is 500 kgm/s^2.
What is the change in velocity per second for any object falling freely under gravity?The change in velocity of a moving object is known as acceleration.
For any object falling freely under gravity, the change in velocity per second or acceleration due to gravity is a constant and is equal to 10 metres per square second (10 m/s^2).
The change in momentum of a body is given as follows:
Momentum = mass × velocity Change in momentum = mv - muChange in momentum = m(v - u)acceleration = v - uwhere m is mass, v is final velocity and u is final velocity.
Mass of the student = 50 Kg
Change in momentum each second = 50 kg × 10 m/s^2 = 500 kgm/s^2
Therefore, the increase in velocity of the student per second is 10 m/s^2 and her change in momentum each second is 500 kgm/s^2.
Learn more about change in momentum at: https://brainly.com/question/27778439
#SPJ1
If you had to choose a theory that best represents your own view of development, would you choose a single theory or would you select components of several different theories? what aspect of your chosen theory (or theories) make it more attractive than others
I would select components of several different theories and the aspect which will be more attractive will be the one which has similarities and accurate.
What is a Theory?This is defined as a proposed explanation for a particular phenomenon or occurrence.
Components of several different theories will bring different dimensions and factors to the occurrence which will help in its thorough analysis.
Read more about Theory here https://brainly.com/question/11555274
#SPJ1
Which statement belongs to daltons atomic theory
Atoms cannot be broken down into smaller pieces is the statement belongs to daltons atomic theory. Option B is correct.
What is an atom?The atom consists of matter that may be split without releasing electrical charges. It's also the smallest unit of matter with chemical element features.
The complete question is:
"Which statements belong to Dalton's atomic theory? Select all that apply.
A)Atoms cannot be created or destroyed.
B)Atoms cannot be broken down into smaller pieces.
C)All atoms of an element are identical.
D)Chemical reactions cause atoms to be rearranged."
According to Dalton's atomic hypothesis, atoms cannot be broken down into smaller bits.
Hence, option B is correct.
To learn more about the atom refer to the link;
https://brainly.com/question/1566330
#SPJ1
How does newton’s third law of motion relate to a catapult?
PLEASE ANSWER ASAP. WILL GIVE BRAINLIEST
Answer: the force when the catapult swings has the same force as it does when coming down
Explanation:
for every reaction there is an equal opposite reaction
5.4.2 Test (CST): Earth's Resources
Question 5 of 15
▬▬
The human population grows by about 2 percent each year, showing
growth.
OA. exponential
OB. linear
OC. cubic
The human population which grows by about 2 percent each year, is showing linear growth.
What is linear increment?
A linear increment occurs when a sequence increases gradually with a constant value.
If a population increases at the rate of 2%, the incremental rate or constant factor is 2%, thus, we can conclude that the human population which grows by about 2 percent each year, is showing linear growth.
Learn more about linear increment here: https://brainly.com/question/2511791
#SPJ1
Which would result in a judge who is sitting beside the testing ground observing the tennis ball having a speed of 7 m/s?
Considering the frames of reference, the robot has to fire backwards at a speed of 2m/s.
What is relative velocity?The relative velocity is obtained based on the inertial frame of reference. The term velocity is always measured relatively.
Given that the inertial frame of reference is relative to the moving frame then; 7m/s - 9 m/s = -2m/s.
It then follows that the robot has to fire backwards at a speed of 2m/s.
Missing parts:
Basim’s robotics team builds a robot that travels at 9 m/s and can fire a tennis ball at a target.
Which would result in a judge who is sitting beside the testing ground observing the tennis ball having a speed of 7 m/s?
The robot fires the ball forward with a speed of 7 m/s.
The robot fires the ball backward with a speed of 7 m/s.
The robot fires the ball backward with a speed of 2 m/s.
The robot fires the ball forward with a speed of 2 m/s.
Learn more about frame of reference:https://brainly.com/question/12222532?
#SPJ1
Answer:
C. the robot fires the ball backward with a speed of 2 m/s.
4. A weightlifter lifts a set of weights a vertical distance of 2 meters. If a constant net force of 350 N is exerted on the weights, what is the net work done on the weights?
Answer:
700 J
Explanation:
Work = Force * Distance
Work = 350 N * 2 M = 700 J
(
the average power transferred to the solar panels by sunlight is 26 000 w
calculate the average energy transferred to the solar panels in 30 seconde
use the equations
energy transferred = power time
Answer:
P = E / t definition of power is energy / unit time
1 W = 1 Joule / sec definition of 1 Watt of power
E = 2.6E4 J/s * 30 s = 7.8E5 Joules = 780,000 Joules
The average power transferred to the solar panels by sunlight is 26 000 w. The average energy transferred to the solar panels in 30 seconds is 780,000 joules.
To calculate the average energy transferred to the solar panels in 30 seconds, we can use the equation:
Energy transferred = Power × Time
Given that the average power transferred to the solar panels is 26,000 watts and the time is 30 seconds, we can substitute these values into the equation:
Energy transferred = Power × Time
Energy transferred = 26,000 × 30
Energy transferred = 780,000 watt-seconds
Since the watt-second is equivalent to the joule (J), the energy transferred to the solar panels is 780,000 joules.
Therefore, the average energy transferred to the solar panels in 30 seconds is 780,000 joules.
To know more about energy and power:
https://brainly.com/question/34423421
#SPJ5
Which of the following is NOT an example of evidence that can be used to support the theory of evolution?
A. DNA evidence
B. Embryonic structures
C. Anatomical structures
D. Similar appearances in modern day organisms
HELP!
how did Mario Molina contribute to science?
i need like a mini paragraph:(
Mario Molina helped to bring about the 1987 Montreal Protocol on substances that result in depletion of the Ozone Layer.
What is ozone layer?The topmost layer of the atmosphere which protect the harmful UV rays from the Sun to reach the Earth surface.
Mario Molina has the great contribution in science field. He tried hard and succeeded in passing an international agreement to eliminate CFCs also called as Chloro Fluoro Carbons and other ozone-depleting chemicals.
These CFCs were used in jet planes which depleted the ozone layer and a hole was observed over Antarctica.
Learn more about ozone layer.
https://brainly.com/question/14330630
#SPJ1
a carmboard 4ft x 4ft Square has the queen at the centre the queen is hit by the striker moves to the front edge, rebounds and goes inta hole behind the striking line. find the magnitude of displacement of queen a) from the centre to front edge b) from the front end edge to hole (c) from centre to hole.
Diagonal of cardboard=displacement to hole
√4²+4²4√2So displacement till edge
4√2/22√2Total distance
4√2+2√26√2ftFrom centre to hole displacement
2√2when two bodies of diffrent temprature in contact, heat will
Answer:
When two bodies at different temperatures are placed in thermal contact with each other, heat flows from the body at a higher temperature until they both reach the same temperature.
Explanation:
A bat strikes a 0.145 kg baseball with force of 5800 N. What acceleration does the baseball experience?
Answer:
40,000 m/s²
Explanation:
The formula is given as Force = mass × acceleration, so then acceleration = Force / mass.
Therefore...
5800 N ÷ 0.145 kg = 40,000 m/s²
The student notices that the electronic balance has a zero error, so it shows
mass readings that are all slightly too small.
This means that the density value is
A)incorrect and slightly too large
B)incorrect and slightly too small
C)correct because the student used three significant figures
D)correct because the mass of the block is more than zero
The student notices that the electronic balance has a zero error, so it shows mass readings that are all slightly too small. This means that the density value is incorrect and slightly too small. The correct option is B.
The density is the ratio of the mass and the volume of the object. It is denoted by ρ.
ρ = mass/Volume = m/V
The student notices that the electronic balance has a zero error, so it shows mass readings that are all slightly too small.
As mass is directly proportional to density. The density will also be slight small when mass reading are all slightly small.
Thus, the correct option is B.
Learn more about density.
https://brainly.com/question/9215083
#SPJ1
A satellite with a mass of 120 kg fires its rocket thrusters, which give an impulse of 7440 kg-m/s. What was the total change in the velocity of the satellite — that is, what was the total AV?
A. 17 m/s
B. 88 m/s
C. 45 m/s
D. 62 m/s
From the calculation and the momentum of the body, the velocity is 62 m/s
What is momentum?The term momentum refers to the product of mass and velocity. Now recall that the rate of change of momentum is equal to the impressed force.
Hence;
7440 kg-m/s = 120 kg * v
v= 7440 kg-m/s/120 kg
v = 62 m/s
Learn more about momentum:https://brainly.com/question/24030570
#SPJ1