Answer:
the following variables
a solid cubic centimeter of platinum weighs 21.5 N. if this cube of platinum is placed under water, what volume of water is displaced? what weight of water is displaced? (Hints: 1 cm3 of water has a mass of 1 gram; 1 gram weighs 0.0098 N; density of platinum = 21.5 g/cm3.)
Answer:
Mp =Pp g where p = density of solid Platinum
Wp = Mp Pp g weight of mass M
Volume displaced is 1 cm^3
Weight of water = .0098 N since 1 cm^3 displaced
Or Ww = 1 cm^3 * .001 kg / cm^3 * 9.8 N/kg = .0098 N
A record is spinning on a turntable. A record is a uniform disk of mass 1.00 kg and a radius of 0.13 m that spins around an axis through its center. The record is initially spinning at 10 rad/s. Then the motor is turned off and the record slows to a stop with constant angular acceleration. As the record is slowing down it spins through 6.37 revolutions. What is the magnitude of the net torque acting on the record as it slows down
Answer:
T = 0.01 Nm
Explanation:
First, we will calculate the angular acceleration of the disk:
[tex]2\theta\alpha = \omega_f^2-\omega_i^2[/tex]
where,
θ = angular displacement = (6.37 rev)(2π rad/1 rev) = 40.02 rad/s
α = angular acceleration = ?
ωi = initial angular speed = 10 rad/s
ωf = final angular speed = 0 rad/s
Therefore,
[tex](2)(40.02\ rad/s)\alpha = (0\ rad/s)^2-(10\ rad/s)^2[/tex]
α = -1.25 rad/s²
negative sign shows deceleration
α = 1.25 rad/s²
Now, we will calculate the moment of inertia of disk:
[tex]I = \frac{1}{2}mr^2[/tex]
where,
I = Moment of Inertia = ?
m = mass of disk = 1 kg
r = radius of disk = 0.13 m
Therefore,
[tex]I = \frac{1}{2} (1\ kg)(0.13\ m)^2[/tex]
I = 0.00845 kg.m²
Now, the torque can be given as:
T = Iα
T = (0.00845 kg.m²)(1.25 rad/s²)
T = 0.01 Nm
A polar bear walks 2.5 meters to the right and then back to the left to exactly where he started. His displacement would be
?
A.
5 meters
B.
2.5 meters
C.
O meters
D.
No way to determine with given information
g 2. In a laboratory experiment on standing waves a string 3.0 ft long is attached to the prong of an electrically driven tuning fork which vibrates perpendicular to the length of the string at a frequency of 60 Hz. The weight (not mass) of the string is 0.096 lb. a) [5 pts] What tension must the string be under (weights are attached to the other end) if it is to vibrate in four loops
Answer:
The tension in string will be "3.62 N".
Explanation:
The given values are:
Length of string:
l = 3 ft
or,
= 0.9144 m
frequency,
f = 60 Hz
Weight,
= 0.096 lb
or,
= 0.0435 kgm/s²
Now,
The mass will be:
= [tex]\frac{0.0435}{9.8}[/tex]
= [tex]0.0044 \ kg[/tex]
As we know,
⇒ [tex]\lambda=\frac{2L}{n}[/tex]
On substituting the values, we get
⇒ [tex]=\frac{2\times 0.9144}{4}[/tex]
⇒ [tex]=0.4572 \ m[/tex]
or,
⇒ [tex]v=f \lambda[/tex]
⇒ [tex]=0.4572\times 60[/tex]
⇒ [tex]=27.432 \ m/s[/tex]
Now,
⇒ [tex]v=\sqrt{\frac{T}{\mu} }[/tex]
or,
⇒ [tex]T=\frac{m}{l}\times v^2[/tex]
On putting the above given values, we get
⇒ [tex]=\frac{0.0044}{0.9144}\times (27.432)^2[/tex]
⇒ [tex]=\frac{752.51\times 0.0044}{0.9144}[/tex]
⇒ [tex]=3.62 \ N[/tex]
A diver comes off a board with arms straight up and legs straight down, giving her a moment of inertia about her rotation axis of 18kg⋅m2. She then tucks into a small ball, decreasing this moment of inertia to 3.6kg⋅m2. While tucked, she makes two complete revolutions in 1.2s.
Required:
If she hadn't tucked at all, how many revolutions would she have made in the 1.5 s from board to water?
Answer:
θ₁ = 0.5 revolution
Explanation:
We will use the conservation of angular momentum as follows:
[tex]L_1=L_2\\I_1\omega_1=I_2\omega_2[/tex]
where,
I₁ = initial moment of inertia = 18 kg.m²
I₂ = Final moment of inertia = 3.6 kg.m²
ω₁ = initial angular velocity = ?
ω₂ = Final Angular velocity = [tex]\frac{\theta_2}{t_2} = \frac{2\ rev}{1.2\ s}[/tex] = 1.67 rev/s
Therefore,
[tex](18\ kg.m^2)\omega_1 = (3.6\ kg.m^2)(1.67\ rev/s)\\\\\omega_1 = \frac{(3.6\ kg.m^2)(1.67\ rev/s)}{(18\ kg.m^2)}\\\\\omega_1 = \frac{\theta_1}{t_1} = 0.333\ rev/s\\\\\theta_1 = (0.333\ rev/s)t_1[/tex]
where,
θ₁ = revolutions if she had not tucked at all = ?
t₁ = time = 1.5 s
Therefore,
[tex]\theta_1 = (0.333\ rev/s)(1.5\ s)\\[/tex]
θ₁ = 0.5 revolution
A bat emits a 40 kHz chirp to locate flying insects. If the speed of sound is 340 m/s and a bat hears the echo from the moth after 0.6 seconds, then how far away is the moth?
102 m
Explanation:
The time 0.6 sec is the time it took for the sound to travel from the bat to the moth and back. So it took 0.3 sec for the sound to reach the moth. From the definition of speed, the distance of the moth d to the bat is given by
v = d/t ---> d = vt = (340 m/s)(0.3 sec) = 102 m
A cup has a mass of 0.0650 kg and a
volume of 0.000250 m3, and is floating in fresh water. Pennies are put into the
cup until the top of the cup is level with the water line. What is the mass of the
pennies in the cup?
Answer: 0.185
Explanation:
Trust bro
The correct answer about law of floatation is, “0.185 kg”.
What are the conditions for object to float on water?The object's average density must be lower than the density of the fluid in which it must float.The fluid's upward push force on the item must match the object's entire weight.The objects's volume which is submerged in water has to be large enough so that a large amount of water can be displaced.
What is law of floatation?
When a body which is floating in a liquid, the amount of weight of liquid that is displaced by the body's submerged portion equals the body's total weight.
How to solve this question?
Volume of water that the cup has displaced = volume of cup
Volume of water that the cup has displaced = 0.000250 m³
Mass of water the cup has displaced = Density of water × Volume of water that the cup has displaced
Given that 1000 kg/m³ is the water density,
Mass of water the cup has displaced = 1000 X 0.000250 = 0.250 kg
Mass of water the cup has displaced = 0.250 kg
By law of flotation
Mass of water the cup has displaced = Mass of cup + Mass of pennies
0.250 Kg = 0.065 Kg + Mass of pennies in the cup (in Kg)
Mass of pennies in the cup = 0.250 - 0.065
Mass of pennies in the cup = 0.185 kg
Hence the mass of the pennies in cup came out be 0.185 Kg after solving.
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What unit is current measured in?
Two organisms that can reproduce and produce fertile offspring are defined as a: *
Learning Goal: To understand the concept of moment of inertia and how it depends on mass, radius, and mass distribution.
In rigid-body rotational dynamics, the role analogous to the mass of a body (when one is considering translational motion) is played by the body's moment of inertia. For this reason, conceptual understanding of the motion of a rigid body requires some understanding of moments of inertia. This problem should help you develop such an understanding.
The moment of inertia of a body about some specified axis is I = cmr^2, where c is a dimensionless constant, m is the mass of the body, and r is the perpendicular distance from the axis of rotation. Therefore, if you have two similarly shaped objects of the same size but with one twice as massive as the other, the more massive object should have a moment of inertia twice that of the less massive one. Furthermore, if you have two similarly shaped objects of the same mass, but one has twice the size of the other, the larger object should have a moment of inertia that is four times that of the smaller one.
Two spherical shells have their mass uniformly distrubuted over the spherical surface. One of the shells has a diameter of 2 meters and a mass of 1 kilogram. The other shell has a diameter of 1 meter. What must the mass m of the 1-meter shell be for both shells to have the same moment of inertia about their centers of mass?
Answer:
m₂ = 4 kg
Explanation:
The moment of inertia is defined by
I = ∫ r² dm
for bodies with high symmetry it is tabulated, for a spherical shell
I = 2/3 m r²
in this case the first sphere has a radius of r₁ = 2m and a mass of m₁ = 1 kg, the second sphere has a radius r₂ = 1m.
They ask what is the masses of the second spherical shell so that the moment of inertia of the two is the same.
I₁ = ⅔ m₁ r₁²
I₂ = ⅔ m₂ r₂²
They ask that the two moments have been equal
I₁ = I₂
⅔ m₁ r₁² = ⅔ m₂ r₂²
m₂ = (r₁ / r₂) ² m₁
let's calculate
m₂ = (2/1) ² 1
m₂ = 4 kg
When an object is fully converted into energy the amount of energy liberated is
3.6×1017 J, what is the mass of the substance?
Answer:
Mass, m = 4 kg
Explanation:
Given the following data;
Energy = 3.6 * 10^17 Joules
We know that the speed of light is equal to 3 * 10⁸ m/s.
To find the mass of the substance;
The theory of special relativity by Albert Einstein gave birth to one of the most famous equation in science.
The equation illustrates, energy equals mass multiplied by the square of the speed of light.
Mathematically, the theory of special relativity is given by the formula;
[tex] E = mc^{2} [/tex]
Where;
E is the energy possessed by a substance.m is the mass.c is the speed of light.Substituting into the formula, we have;
[tex] 3.6 * 10^{17} = m * 300000000^{2} [/tex]
[tex] 3.6 * 10^{17} = m * 9*10^{16} [/tex]
[tex] m = \frac {3.6 * 10^{17}}{9*10^{16}} [/tex]
Mass, m = 4 kg
A cargo spacecraft was orbiting the earth. It is equipped with rocket and has an initial mass of 30 metric ton. It wants to catch up with the international space station to deliver the cargo. So its rocket engine was fired for 1 minute. The engine ejects mass at a rate of 30 kg/s with an exhaust velocity of 3.1 km/s. The pressure at the nozzle exit is 5 kPa and the diameter of exit area is 94.4 cm. What is the thrust of the engine in a vacuum
Answer:
Explanation:
A cargo spacecraft was orbiting the earth. It is equipped with rocket and has an initial mass of 30 metric ton. It wants to catch up with the international space station to deliver the cargo. So its rocket engine was fired for 1 minute. The engine ejects mass at a rate of 30 kg/s with an exhaust velocity of 3.1 km/s. The pressure at the nozzle exit is 5 kPa and the diameter of exit area is 94.4 cm. What is the thrust of the eng
Two creatures sit on a horizontal frictional rotating platform. The platform rotates at a constant speed. The creatures do not slip off as it rotates.
ASSUME:
Red has a mass of 5 kg
Red is 1.5 m from the center
Red has a speed of 9 m/s
Blue has a mass of 25 kg
Blue has a speed of 1.8 m/s
The force of friction on Red is EQUAL to the force of friction on Blue
DETERMINE:
How far from the center is Blue
Answer:
M v^2 / R = centripetal force
For Red: M v^2 / R = 5 * 9^2 / 1.5 = 270
For Blue M v^2 / R = 270 = 25 * 1.8^2 / Rb
So Rb = 25 * 1.8^2 / 270 = .3 m
Please help, confused on this whole lesson
Answer:
1,4,3and 2 would happen hope this helps
An inventor claims to have developed a power cycle capable of delivering a net work output of 400 kJ for an energy input by heat transfer of 1200 kJ. The system undergoing the cycle receives heat from a source of 550K and rejects heat to a sink of 350K. Determine if this is a valid claim.
Answer: Valid claim
Explanation:
Given
Work output is [tex]W=400\ kJ[/tex]
Work input is [tex]Q=1200\ kJ[/tex]
The temperature of the source [tex]T_h=550\ K[/tex]
The temperature of the sink is [tex]T_l=350\ K[/tex]
Efficiency is given by
[tex]\eta =\dfrac{\text{W}}{\text{Q}}\times 100[/tex]
Insert the values
[tex]\Rightarrow \eta=\dfrac{400}{1200}\times 100\\\\\Rightarrow \eta=\dfrac{100}{3}\\\\\Rightarrow \eta=33.3\%[/tex]
For ideal cycle it is
[tex]\Rightarrow \eta=\dfrac{T_h-T_l}{T_l}\times 100\\\\\Rightarrow \eta=\dfrac{550-350}{550}\times 100\\\\\Rightarrow \eta=36.36\%[/tex]
The efficiency of the cycle is less than the ideal situation, therefore, it is valid claim.
When silver nitrate and beryllium chloride react, silver chloride and beryllium nitrate form. What are the coefficients in this equation? (Note: Be sure to keep the reactants and products in the same order that they appear in the question.)
A. 2,1,1,2
B. 1,2,2,1
C. 1,2,1,2
D. 2,1,2,1
Answer:
D. 2,1,2,1
Explanation:
The equation of the reaction is; 2AgNO3 + BeCl2 + ---------》2AgCl + Be(NO3)2
The rule applied in balancing chemical reaction equation is that the number of atoms of each element on the reactants side must be the same as the number of atoms of the same element on the products sides.
If this rule is properly applied to the reaction between silver nitrate and beryllium chloride to form silver chloride and beryllium nitrate , the coefficients in the equation are; 2,1,2,1
arcsin 0.9331 in degrees
Answer:
68.9233231661
Explanation:
Just put it into your calculator, shift sin should do it but it will come up like this: [tex]sin^{-1}[/tex] which is the same as arcsin
Please please help me please please help please please
Answer:
Refraction
The rainbow is created because the index of refraction of water droplets changes as a function of wavelength. So, when the light enters the water droplet different colors will bend at different angles thus producing a dispersive effect known as a rainbow.
Answer:
D: Refraction
Explanation:
Refraction is the spitting of the electromagnetic spectrum, or the disembling of colours. For example, white is a mixture of all the colours.
What is the direction of the magnetic force on a positive charge that moves as shown in each of the six cases shown?
Answer:
D:because magmetic force are like factor but the angles of MAGNETIC and FACTORS are same as well!!it soposed to be like force and 1 by 1 to be divided and multiply thus...the DECIMAL have nothing to involved!!
Explanation:
HOPE IT HELPS!!
An echo is heard from a building 0.4 s after you shout "hello." How many feet away is
the building if the air temperature is 27°C? (Velocity of sound in air at 0°C is 1087 ft/s)
Answer:
Circular motion: find period, find radius, find velocity, find centripetal acceleration 27 V= T a =vºlr=rw
Explanation:
1
1 point
The table shows the lengths and diameters of four copper wires.
Which wire has the least resistance?
length/m
diameter/mm
A
0.50
1.0
B
0.50
2.5
С
0.75
1.0
D
0.75
2.5
А
B
D
Answer:
where is the table?????????
The wire has a length of 0.50 m and a diameter of 2.5 mm and has the least resistance, so, option B is correct.
What is resistance?A substance's ability to obstruct the flow of electrical current is referred to as resistance. It is symbolized by the capital letter R. The ohm, frequently written as a word and sometimes represented by the capital Greek letter omega, is the unit of resistance that is typically used.
Given:
The length of the wire A = 0.50 m and the diameter is 1 mm,
The length of the wire B = 0.50 m and the diameter is 2.5 mm,
The length of the wire C = 0.75 m and the diameter is 1 mm,
The length of the wire D = 0.75 m and the diameter is 2.5 mm,
Calculate the L / Area factor of all the wires as shown below,
L / Area factor of A = 0.50 / π × 0.0005²
L / Area factor of A = 636619.8
L / Area factor of B = 0.50 / π × 0.00125²
L / Area factor of B = 101859
L / Area factor of C = 0.75 / π × 0.0005²
L / Area factor of C = 955414
L / Area factor of D = 0.75 / π × 0.00125²
L / Area factor of D = 152866
As we can see, if the L / Area factor of B is less, then its resistance will be the least.
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what do electrons and holes make when they are moving
Answer:
Holes are formed when electrons in atoms move out of the valence band (the outermost shell of the atom that is completely filled with electrons) into the conduction band. (the area in an atom where electrons can escape easily) which happens everywhere in a semiconductor. When an electron and a hole interact and recombine the energy is not transferred into heat energy or thermal vibrations. instead the energy is transferred into an electron within the conduction band which is then promoted to an energy higher in condition band.
Explanation:
So considering that information, electrons and holes make a semiconductor when moving.
When monochromatic light of an unknown wavelength falls on a sample of aluminum, a minimum potential of 2.27 V is required to stop all of the ejected photoelectrons. (The work function for aluminum is 4.08 eV.) HINT (a) Determine the maximum kinetic energy (in eV) of the ejected photoelectrons. eV (b) Determine the maximum speed (in m/s) of the ejected photoelectrons. m/s (c) Determine the wavelength in nm of the incident light. nm
Answer:
a) KE max = 3.632 * 10^{-19}
b) v = 6.31 * 10^5 m/s
c) Lambda = 195 nm
Explanation:
a) Work done is given by equation
W = V * q = change in kinetic energy = Final KE – Initial KE
Substituting the given values, we get –
V * 1.6*10^{-19} =0 - Initial KE
KE max = 2.27 * 1.6*10^{-19} = 3.632 * 10^{-19}
b) As we know KE = 0.5 mv^{2}
Substituting the given values, we get –
3.632 * 10^{-19} = 0.5 * (9.11 * 10^{-31}) v^2
v = 6.31 * 10^5 m/s
c) Incident energy = W + K max
Substituting the given values we get
hc/lambda = 4.08 * 1.6 * 10^{-19} J + 3.632 * 10^{-19} J
6.626 *10^{-34} * 3*10^8/lambda = 4.08 * 1.6 * 10^{-19} J + 3.632 * 10^{-19} J
Lambda = 1.95 * 10^7
Lambda = 195 nm
Help please ASAP will give brainliest
Answer:
42.64
Explanation:
2x=2
7x=5
12x=1.4
17.5x=21.5
Platinum is used in resistance thermometer for industrial applications because of?
platinum is used because it is more stable, provides accurate results and has a broad temperature range.
Match these items.
1. effect observed when light from an object in cool air passes through warm air
2. line perpendicular to a surface
3. splitting of light into its component colors angle of incidence
4. alignment of light into a single vibrational direction
5. larger angle as light passes from air to water
6. cause of the sky's color
7. bouncing of light rays reflection
8. bending of light between media
9. ratio of speeds of light
10. inability of light to escape a low-velocity medium due to a large angle of approach refraction
a. scattering
b.dispersion
c.angle of incidence
d.index of refraction
e.mirage
f.reflection
g.normal
h.total inertial reflection
i.polarization
j.refraction
Answer:
1. effect observed when light from an object in cool air passes through warm air
→ h. total internal reflection
2. line perpendicular to a surface
→ g. normal.
3. splitting of light into its component colors angle of incidence
→ b. dispersion.
4. alignment of light into a single vibrational direction
→ i. polarization
5. larger angle as light passes from air to water
→ c. angle of incidence
6. cause of the sky's color
→ f. reflection
7. bouncing of light rays reflection
→ f. reflection
8. bending of light between media
→ j. refraction.
9. ratio of speeds of light
→ d. index of refraction.
10. inability of light to escape a low-velocity medium due to a large angle of approach refraction
→ scattering.
The figure below shows regions of the electromagnetic
spectrum
Gamma
Radio Microwaves Infrared Visible Ultraviolet X-rays Rays
Which of the following waves has the highest frequency?
{GAMMA RAYS}
Answer:
The electromagnetic spectrum in order of increasing frequency is - radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.
The frequency of the gamma rays is >3×10
19
m.
Hence, the gamma rays has the maximum frequency in the electromagnetic spectrum.
What does Binding Energy in the nucleus represent?
Answer:
Nuclear binding energy is the energy required to split a nucleus of an atom into its component parts: protons and neutrons, or, collectively, the nucleons. The binding energy of nuclei is always a positive number, since all nuclei require net energy to separate them into individual protons and neutrons.
I hope you find this helpful.
TAKE 100 POINTS!!!please help look the picture!!!!
Answer:
A major challenge in the drug delivery field is to enhance transport of therapeutics across biological barriers such as the blood brain barrier (BBB), the small intestine, nasal, skin and the mouth mucosa.
Answer:
An aqueous stagnant layer that overlies the apical membrane and the subepithelial blood flow are potential barriers to the absorption of drugs that readily penetrate the absorbing cell of the epithelium. The apical, basal, and basement membranes are potential barriers to the absorption of less permeable drugs
How many tons and pounds (like together, not two different numbers) is 9,920 pounds? Please help,
Answer:
About 5 tons (4.96)