Answer:
A
Explanation:
When switches 1 and 2 are 'on' or 'closed' the circuit becomes a short
Season and date for this person
Answer:
summer June 21 is the answer
What is the force of gravity (in newtons) acting between the earth and a 5 kg bowling ball that is resting on the surface of the earth
Answer:
49 N
Explanation:
F = m a
= 5 * 9.81 =~ 49 N
A magnetic field B = 20.0 mT points in the +y-direction. A rectangular circuit of wire with an area of 200 cm2, which is initially in the xz-plane, rotates into the xy-plane as shown. If this process is smooth and takes 1.2 seconds, what is the magnitude of the emf induced in the loop?
If the process is smooth and only takes the given time, the magnitude of the emf induced in the loop is 3.33 × 10⁻⁴Volts.
Given the data in the question
Magnetic field; \(B = 20mT = 20 * 10^{-3}T\)Area; \(A = 200cm^2 = 0.02m^2\)Time; \(\delta t = 1.2s\)Magnitude of the emf induced in the loop; \(|e| =\ ?\)
From Faraday's law, formula for Induced emf is given as:
\(|e| = -\frac{\delta\theta}{\delta t} \\\\|e| = -\frac{\delta (BAcos\theta)}{\delta t} \\\\|e| = -BA\frac{\delta (cos\theta)}{\delta t}\)
Where \(\delta\theta\) is the change in flux, \(\delta t\) is time taken to change the flux, B is the Magnetic field and A is the area.
We know that; \(\theta = 0^o\ to\ 90^o\), so
\(|e| = -BA\frac{(cos90^o -cos0^o)}{\delta t}\)
Now, we substitute in our given valueslux
\(|e| = [-(20*10^{-3}T)*0.02m^2]\frac{(cos90^o -cos0^o)}{1.2s}\\\\|e| = (-0.0004Tm^2)\frac{(0-1)}{1.2s}\\\\|e| = \frac{0.0004Tm^2}{1.2s}\\\\|e| = 3.33*10^{-4}Volts\)
Therefore, if the process is smooth and only takes the given time, the magnitude of the emf induced in the loop is 3.33 × 10⁻⁴Volts
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Starting from rest, a car takes 2.4 s to travel the first 15 m. Assuming a constant acceleration, how long will it take the car to travel the next 15 m?
A) 1.0s
B) 3.6s
Answer:
letter B.
Explanation:
Answer: A
0.1
Explanation: I did this
A charged capacitor and an inductor are connected in series. At time t = 0, the current is zero, but the capacitor is charged. If T is the period of the resulting oscillations, the next time, after t = 0 that the energy stored in the magnetic field of the inductor is a maximum is
Answer:
t = T / 2 all energy is stored in the inductor
Explanation:
The circuit described is an oscillating circuit where the charge of the condensation stops the inductor and vice versa, in this system the angular velocity of the oscillation is
w = √1/LC
2π / T =√1 / LC
T = 2π √LC
The energy is constant and for the initial instant it is completely stored in the capacitor
Uc = Q₀² / 2C
In the process, the capacitor is discharging and the energy is stored in the inductor until when the charge in the capacitors zero, all the energy is stored in the inductor
U = L I² / 2
in the intermediate instant the energy is stored in the two elements.
Since the period of the system is T for time t = 0 all energy is stored in the capacitor and for t = T / 2 all energy is stored in the inductor
After t = 0 the maximum energy stored in the magnetic field of the inductor is equal to \(U'=\dfrac{L I^{2}}{2}\) for the time period, half of period of oscillation (t = T/2).
The given problem is based on the charging and discharging concepts of capacitor. An oscillating circuit is a circuit where the charge of the capacitor stops the inductor and vice versa, in this system the angular frequency of the oscillation is given as,
\(\omega =\dfrac{1}{\sqrt{LC}}\\\\\\\dfrac{2 \pi}{T} =\dfrac{1}{\sqrt{LC}}\\\\\\T = 2\pi \times \sqrt{LC}\)
here, T is the period of oscillation.
Also, the energy stored in the capacitor is constant and for the initial instant it is completely stored in the capacitor. So, the energy stored is given as,
\(U =\dfrac{Q^{2}}{2C}\)
here, C is the capacitance.
In the process, the capacitor is discharging and the energy is stored in the inductor until when the charge in the capacitors zero, all the energy is stored in the inductor. So, the expression for the energy stored in the inductor is,
\(U'=\dfrac{L I^{2}}{2}\)
here, L is the inductance and I is the current.
Note :- The period of the system is T for time t = 0 all energy is stored in the capacitor and for t = T / 2 all energy is stored in the inductor.
Thus, we conclude that after t = 0 the maximum energy stored in the magnetic field of the inductor is equal to \(U'=\dfrac{L I^{2}}{2}\) for the time period, half of period of oscillation (t = T/2).
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what is the force acting on point O? Check picture for diagram! please and thank you
The magnitude of the force acting at point O is determined as 240 N.
What is the magnitude of the force at point O?The magnitude of the force at point O is calculated by applying the principles of moment as shown below.
sum of the clockwise moment = sum of the anticlockwise moment
F₀(2 m + 2m + 2m) = 260 N (2m + 2 m ) + 200 N ( 2 m )
where;
F₀( is the force at point O6F₀ = 260 (4) + 200(2)
6F₀ = 1,440
F₀ = 1440 / 6
F₀ = 240 N
Thus, the magnitude of the force acting at point O is determined as 240 N.
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4. Water is flowing at 12m/s in a horizontal pipe under a pressure of 600kpa
radius 2cm.
a. What is the speed of the water on the other side of 0.5cm radius?
b. What is the pressure of the other side?
Answer:
a. 192 m/s
b. -17,760 kPa
Explanation:
First let's write the flow rate of the liquid, using the following equation:
Q = A*v
Where Q is the flow rate, A is the cross section area of the pipe (A = pi * radius^2) and v is the speed of the liquid. The flow rate in both parts of the pipe (larger radius and smaller radius) needs to be the same, so we have:
a.
A1*v1 = A2*v2
pi * 0.02^2 * 12 = pi * 0.005^2 * v2
v2 = 0.02^2 * 12 / 0.005^2
v2 = 192 m/s
b.
To find the pressure of the other side, we need to use the Bernoulli equation: (600 kPa = 600000 N/m2)
P1 + d1*v1^2/2 = P2 + d1*v2^2/2
Where d1 is the density of the liquid (for water, we have d1 = 1000 kg/m3)
600000 + 1000*12^2/2 = P2 + 1000*192^2/2
P2 = 600000 + 72000 - 1000*192^2/2
P2 = -17760000 N/m2 = -17,760 kPa
The speed in the smaller part of the pipe is too high, the negative pressure in the second part means that the inicial pressure is not enough to maintain this output speed.
An electric device uses 650 watts of power. If the voltage is 120 volts, what is the resistance?
The resistance of the electric device using a power of 650 watts is approximately 27.7 ohms.
How determine resistance from power and votage?Ohm’s law states that the potential difference between two points is directly proportional to the current flowing through the resistance.
Hence
V = IR
R = V/I
Where V is the voltage or potential difference, potential difference, I is the current and R is the resistance.
We need to first find the electric current I.
Note:
Power = Voltage × Current.
Hence:
Current I = Power/Votage
Plug in the values
I = 650 / 120
I = 13/3 A
Substituting the values of voltage and current intio the above formula, we can calculate the resistance:
R = V/I
R = 120 / (13/3)
R = 27.7 ohms
Therefore, the resistance is approximately 27.7 ohms.
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A ball is thrown straight up into the air. Which of the following best describes the energy present at various stages?
There is more energy at the top of the ball's path than there is at the bottom.
The total amount of energy varies, with more energy at the bottom and less at the top of the path.
At the very top, most of the energy is potential and just before it hits the ground, most of the energy is kinetic.
At the very top, most of the energy is kinetic and just before it hits the ground, most of the energy is potential.
Answer:
Uhh 2 one
Explanation
Black hole radius, large to small. What is the Schwarzschild radius of (a) the supermassive black hole with
4.0×10 10
solar masses in the Abell 85 galaxy cluster, (b) the imaged
M87
black hole with
6.4×10 9
solar masses, (c) an intermediate mass black hole with
1.0×10 4
solar masses, (d) the Sun, with mass
1.99×10 30
kg
, and (e) a micro black hole with a mass of
2.0×10 −8
kg
The Schwarzschild radius of different materials supermassive black hole and M87black hole are\(4.80528 \times 10^{-19} and 9.49 \times 10^{-18}\) respectively.
What is a black hole's Schwarzschild radius?The distance connecting a Schwarzschild black hole's centre and event horizon is known as the Schwarzschild radius. The event horizon is positioned above the Schwarzschild radius, that starts at the black hole's centre. Black holes have a rather important characteristic called the Schwarzschild radius.
Schwarzschild radius (Rs)= 2GM/c²
G=> gravitational constant = \(6.674 \times 10^{-11} m^3/kgs^2\)
c=> speed of light =>\(3\times10^{8}m/s\)
M => solar mass
A) Rs of supermassive black hole =>
\(2 \times 6.674 \times 10^{-11} \times 4.0\times10^{1}0/(3\times10^{8})^{2} = 4.80528 \times 10^{-19}\)
B) Rs of M87black hole
\(= 2 \times 6.674 \times 10^{-11} \times 6.4 \times 10^{9} /(3 \times 10^{8})^{2} = 9.49 x 10^{-18}\)
C) Rs of intermediate mass black hole =
\(2 \times 6.674 \times 10^{-11} \times 1.0\times10^{4} /(3\times10^{8})^{2} = 1.48 x 10^{-23}\)
D) Rs of the Sun =
\(2 \times 6.674 \times 10^{-11} \times\frac { 1.99 \times 10^{30}}{(3x10^{8})^{2}} = 2.95 \times 10^{3}\)
E) Rs of micro black hole =>
\(2 \times 6.674 \times 10^-11 x\frac{ 2.0\times 10^{−8}}{(3 \times 10^8)^{2}} = 2.96 \times 10^{-35}\)
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Complete question -
Black hole radius, large to small. What is the Schwarzschild radius of
(a) the supermassive black hole with 4.0×10^10 solar masses in the Abell 85 galaxy cluster
(b) the imaged M87black hole with 6.4×10^9 solar masses
(c) an intermediate mass black hole with 1.0×10^4 solar masses
(d) the Sun, with mass 1.99×10^30 kg
(e) a micro black hole with a mass of 2.0×10^−8 kg
Which of the following bounces light in another direction?
a) Sunglasses
b) lamp
c) mirror
d) prism
Answer:
I do believe the answer is D. prism
Answer:
Explanation:
either all of the above or D <3
Consider a double-paned window consisting of two panes of glass, each with a thickness of 0.500 cm and an area of 0.760 m2 , separated by a layer of air with a thickness of 1.65 cm . The temperature on one side of the window is 0.00 ∘C; the temperature on the other side is 23.0 ∘C. In addition, note that the thermal conductivity of glass is roughly 36 times greater than that of air. Approximate the heat transfer through this window by ignoring the glass. That is, calculate the heat flow per second through 1.65 cm of air with a temperature difference of 23.0 ∘C . (The exact result for the complete window is 24.4 J/s .)
The approximate heat transfer through 1.65 cm of air with a temperature difference of 23.0 °C is approximately 24.4 J/s.
To approximate the heat transfer through the air layer in the double-paned window, we can assume that the glass layers have a negligible impact on the heat flow. The heat transfer can be calculated using Fourier's Law of Heat Conduction, which states that the heat flow (Q) is proportional to the temperature difference (ΔT) and inversely proportional to the thickness (L) and thermal conductivity (k) of the material.
First, we need to calculate the effective thermal conductivity of the air layer due to its thickness and the thermal conductivity ratio between air and glass. Let's denote the thermal conductivity of air as k_air and the thermal conductivity of glass as k_glass. Since glass has a thermal conductivity roughly 36 times greater than air, we have k_glass = 36 * k_air.
Next, we calculate the effective thermal conductivity of the air layer as:
k_eff = (k_air * L_air) / (L_air + k_glass)
Substituting the given values, we have:
k_eff = (k_air * 0.0165 m) / (0.0165 m + 0.005 m) = 0.01309 * k_air
Now, we can calculate the heat flow per second through the air layer using the formula:
Q = (k_eff * A * ΔT) / L_air
Substituting the given values, we get:
Q = (0.01309 * k_air * 0.760 m^2 * 23.0 K) / 0.0165 m = 24.4 J/s
Therefore, the approximate heat transfer through 1.65 cm of air with a temperature difference of 23.0 °C is approximately 24.4 J/s.
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Describe how the composition of gasses changes as you travel up through the Earth’s atmosphere.
Answer:
As you travel up through the Earth's atmosphere, the composition of gases changes. Near the Earth's surface, the atmosphere consists mainly of nitrogen (about 78%) and oxygen (about 21%) with traces of other gases like carbon dioxide and argon. As you go higher, the amount of oxygen decreases, and the concentration of other gases becomes more prominent, such as helium, hydrogen, and ozone.
A spacecraft is traveling with a velocity of Vox-5690 m/s along the +x direction. Two engines are turned on for a time of 865 s. One
engine gives the spacecraft an acceleration in the +x direction of a, 1.45 m/s², while the other gives it an acceleration in the ty
direction of a, -8.66 m/s2. At the end of the firing, what is a) v, and b) vy?
(a) Number i
(b) Number
Units
Units
For a spacecraft is traveling with a velocity of Vox-5690 m/s:
(a) The final velocity (v) is approximately 685.25 m/s.(b) The vertical component of the velocity (vy) is -7484.9 m/s.How to calculate velocity and vertical component?To solve this problem, use the equations of motion to calculate the final velocity and the vertical component of the velocity. Assume that the initial velocity in the y-direction is zero.
Given:
Initial velocity in the x-direction (V₀ₓ) = -5690 m/s
Time of engine firing (t) = 865 s
Acceleration in the x-direction (ax) = 1.45 m/s²
Acceleration in the y-direction (ay) = -8.66 m/s²
(a) To calculate the final velocity (v), use the equation:
v = V₀ₓ + ax × t
Substituting the values:
v = -5690 m/s + 1.45 m/s² × 865 s
v = -5690 m/s + 1254.25 m/s
v ≈ 685.25 m/s
Therefore, the final velocity (v) is approximately 685.25 m/s.
(b) To calculate the vertical component of the velocity (vy), use the equation:
vy = ay × t
Substituting the values:
vy = -8.66 m/s² * 865 s
vy = -7484.9 m/s
Therefore, the vertical component of the velocity (vy) is -7484.9 m/s.
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Which of the following is the best hypothesis?
A. The size of ice crystals in clouds depends on the air temperature.
B. It is fun to fly an airplane through large cumulus clouds.,
C. How big can ice crystals get inside a cloud?
D. Clouds are always found in the atmosphere.
Fig. 3.1 shows the speed/time graph for a journey travelled by a tractor
Q
R
6
spood
m/s
4
2.
P
O
S
200
0
50
100
170
time/s
Fig. 3.1
(a) Use the graph to describe the motion of the tractor during each of the marked sections,
OP
РО
QR
RS
[4)
. An electron has a de Broglie wavelength of 2.80 *
10-10 m. Determine (a) the magnitude of its momentum and (b) its
kinetic energy (in joules and in electron volts
The de- Broglie wavelength of 2.80× 10⁻¹⁰ m is associated with a momentum of 2.36 × 10⁻²⁴ Kg m/s. The kinetic energy will be 3.07 × 10⁻¹⁸ J which is equal to 19.015 ev.
What is de-Broglie wavelength?De-Broglie proposed the dual nature of matter which stated that matter can behave as both wave and particle. For a matter wave, the wavelength of the wave will be the ratio of the Planck's' constant h and its momentum p.
thus, λ = h/p
Given the wavelength = 2.80× 10⁻¹⁰ m.
momentum p = h/λ
= 6.62 × 10 ⁻³⁴ / (2.80× 10⁻¹⁰ m)
= 2.36 × 10⁻²⁴ Kg m/s
The kinetic energy ke = 1/2 mv² = p² /2m.
mass of an electron = 9.1 × 10 ⁻³⁴ Kg.
hence, Ke = (2.36 × 10⁻²⁴ Kg m/s )² / 9.1 × 10 ⁻³⁴ Kg
= 3.07 × 10⁻¹⁸ J.
1 J = 6.24 × 10¹⁸ ev.
thus, KE in ev = 3.07 × 10⁻¹⁸ J × 6.24 × 10¹⁸ ev = 19 ev.
Therefore, the kinetic energy of the electron is 19 ev.
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How might these traits change from individual to individual? (Hint: Do you think the newts are all exactly the same color or size?)
Newts hatch in water, but they spend the most of their lives on land, returning to water only for mating.
They have rough skin, are 8 inches long, and have stubby legs and fangs. In the Pacific Northwest, some of them are toxic.
Rough-skinned newts have brown skin on their backs and bright orange skin on their bellies. When frightened by predators, these newts coil their bodies and show off their orange necks and tails. Predators are warned to stay clear from this orange tint.
It is to be noted that none of the newts are the same traits that is color or size.
What are traits?A phenotypic trait (simply trait or character state) is a distinct variety of an organism's feature that is visible and quantifiable and manifests itself in an observable manner.
For example, eye color (green, blue, brown, and hazel) is a phenotypic feature that is passed down by polygenetic inheritance.
Height, wing length, and hair color are all phenotypes. Phenotypes also include observable traits that may be evaluated in the lab, such as hormone levels or blood cell counts.
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A pyramid was built with approximately 2.3 million stone blocks, each weighing 2.4 tons (1 ton = 2,000 lbm). Find the mass of the pyramid in kg.
Total weight in tons
\(\\ \sf\longmapsto 2.3\times 10^6\times 2.4\)
\(\\ \sf\longmapsto 5.52\times 10^6\)
\(\\ \sf\longmapsto 5520000ton\)
1ton=1000kg\(\\ \sf\longmapsto 5520000\times 1000\)
\(\\ \sf\longmapsto 5520000000kg\)
\(\\ \sf\longmapsto 5.52\times 10^9Kg\)
Block A has mass 1.00 kg and block B has mass 3.00 kg. The blocks collide and stick together on a level, frictionless surface. After the collision, the kinetic energy (KE) of block A is
Answer:
1/2mv²=0
1/2(4kg)(v²)=0
2=-v²
square root -2=v
v=1.414
Block A of mass 1 kg and block B has a mass of 3 kg, then the blocks collide and stick together so the kinetic energy of block A is one-third of the kinetic energy of the block.
What is Kinetic energy?Kinetic energy is a type of power that an item or particle possesses as a result of motion. When an item undergoes work—the transfer of energy—by having subject to a net force, it accelerates and consequently obtains kinetic energy. An object in motion or particle's kinetic energy, which depends on both mass and speed, is one of its features. Any combination of motions, including translation, rotation about an axis, and vibration, may be used as the type of motion.
A body's translational kinetic energy is equal to 1/2mv², or one-half of the sum of its mass, m, and the square of its velocity, v.
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A 2 100-kg pile driver is used to drive a steel i-beam into the ground. the pile driver falls 5.00 m before coming into contact with the top of the beam, and it drives the beam 12.0 cm farther into the ground before coming to rest. using energy considerations, calculate the aver- age force the beam exerts on the pile driver while the pile driver is brought to rest.
GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG
GFHFG
The average force the beam exerts on the pile driver while the pile driver is brought to rest is 878 KN.
What in science is a force?The word "force" has a specific meaning in science. At this level, calling a force a push or a pull is entirely appropriate. A force is not something an object "has in it" or that it "contains." One thing experiences a force from another. There is no distinction between living and non-living things in the concept of a force.
What does a force unit mean?The newton, abbreviated N, is the SI unit of force. The force-relevant base units are The symbol for the length unit known as the meter is m. the kilogram (kg), is a unit of mass. The sign for the unit of time is s or the second.
Given:-
Mass (m) = 2100Kg
The distance it moves the pilling (h) = 0.12 m
The distance over which the driver falls freely (d) = 5.00 m
\(F=\frac{(mg)(h+d)}{d}\)
Substitute values,
Where, g = 9.80 m/s^2
\(F=\frac{(2100kg)(9.80m/s^2)(0.12m+5.00m)}{0.12m}\)
\(F=\frac{(2100kg)(9.80m/s^2)(5.12m)}{0.12m}\)
\(F= 8.78*10^5N\)
\(F=878KN\)
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water flows steadily through a horizontal pipe of varying cross section at one place, the pressure is 130KPa and the speed is 0.6m/s. what is the pressure at another place in the same pipe where the speed is 9.0m/s
Answer:
1950 kpa
Explanation:
9 ÷ .6 = 15 times the speed. so 15 times the pressure 130 x15 = 1950 kpa
A 2-kg object is moving horizontally across a frictionless surface with a speed of 4 m/s. How much force is required to keep the object moving at this speed and in this direction?
Answer:
none
Explanation:
Newton's first law says an object in motion will stay in motion at the same speed and direction unless acted upon by some force.
No force is necessary for the object to keep its speed and direction on a frictionless surface.
Answer:
3. Which of the following is NOT fluid?
Ice
Air
Water vapor
Liquid ice
Answer:
4. If you filled a balloon on Earth and brought it to the moon, it would ________.
Expand
Shrink
Stay the same size, with the same internal pressure
Stay the same size but with different internal pressure.
Answer:
5. Which of the following is the largest in number?
Air molecule son your lungs
Grains of sand on earth
Stars in the galaxy
Insects alive on the planet
Answer:
3. Ice.
4. Stay the same size but with different internal pressure.
5. Stars in the galaxy
Explanation:
Hope it helped!!
Suppose you buy a pair of shoes. They come in a box. You take the shoes
out of the box to wear them. How do the mass and the volume of the shoe
box compare before and after you take the shoes out?
Answer:
unchanged
Explanation:
the box itself has same mass and volume with or without the shoes
A hockey puck attached to a horizontal spring oscillates on a
frictionless, horizontal surface. The spring has force constant 4.50 N/m and the oscillation period is 1.20 s. (a) What is the mass of the puck? (b) During an oscillation, the acceleration of the puck has maximum magnitude 1.20 m/s^2. What is the amplitude of the oscillation?
Answers:
(a) 0.164 kg
(b) 0.0438 m = 4.38 cm
(a) The mass of the puck is 0.16 kg
(b) The amplitude of the oscillation is 4.3 cm.
What is the mass of the puck?The mass of the puck is calculated by applying the formula for the period of the oscillation.
T = 2π √ ( m /k )
T / 2π = √ ( m /k )
T² / 4π² = m/k
m = k ( T² / 4π² )
where;
k is the spring constantT is the period of oscillationm is mass of the puckThe mass of the puck is calculated as;
m = 4.5 ( 1.2² / 4π²)
m = 0.16 kg
The amplitude of the oscillation is calculated as follows;
a = ω²A
where;
ω is the angular frequencyA is the amplitude a is the maximum accelerationω = √ ( k /m )
ω² = k / m
from this equation "a = ω²A" make amplitude "A" the subject of the formula.
A = a / ω²
A = (a) / (k / m)
A = ( 1.2 ) / ( 4.5 / 0.16)
A = (1.2) / ( 0.03556)
A = 0.043 m = 4.3 cm
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The temperature of a cup of coffee varies according to Newton's Law of Cooling: dT dt equals negative k times the quantity T minus A, where T is the temperature of the coffee, A is the room temperature, and k is a positive constant. If the coffee cools from 100°C to 90°C in 1 minute at a room temperature of 25°C, find the temperature, to the nearest degree Celsius of the coffee after 4 minutes.
74
67
60
42
Answer:
Explanation:
Writing out the Newton's Law pf Cooling:
dT/dt = -k * (T - A),
where T is the temperature of the coffee, A is the room temperature, and k is a positive constant.
If the coffee cools from 100°C to 90°C in 1 minute at a room temperature of 25°C,
T = 100
A = 25
dT = 100 - 90 = 10
dt = 1
Putting the figures into the equation:
10/1 = -k * (100 - 25)
k = -10/75°C
After 4 minutes, dT/4 = 10/75 (100 - 25) = 10
dT = 40
Temperature after 4 minutes = 100 - 40 = 60°C
The temperature of a cup of coffee varies according to Newton's Law of Cooling, the temperature of the coffee after 4 minutes is approximately 67°C.
To tackle this problem, we can apply Newton's Law of Cooling's differential equation and solve it using variable separation.
dT/dt = -k(T - A)
At t = 0 (initial condition): T = 100°C
At t = 1 minute: T = 90°C
dT/dt = -k(T - A)
At t = 0: dT/dt = -k(100 - 25)
So,
-10 = -k(75)
k = 10/75
Separating variables and integrating, we have:
1/(T - A) dT = -k dt
∫(1/(T - A)) dT = ∫(-k) dt
ln|T - A| = -kt + C
ln|100 - 25| = 0 + C
ln|75| = C
So, the equation will be:
ln|T - A| = -kt + ln|75|
ln|(T - 25)/(75)| = -kt
Now,
ln|((T - 25)/(75))| = -(10/75)(4)
|((T - 25)/(75))| = \(e^{(-40/75)\)
T - 25 = ± 75 * \(e^{(-40/75)\)
T = 25 ± 75 * \(e^{(-40/75)\)
T ≈ 25 ± 42.42
Therefore, the temperature of the coffee after 4 minutes is approximately:
T ≈ 25 + 42.42 = 67.42°C
Thus, the temperature of the coffee after 4 minutes is approximately 67°C.
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What is scintillator
Answer:
Scintillators are materials that are able to convert high energy radiation such as X or gamma-rays to a near visible or visible light. They are widely used as detectors in medical diagnostics, high energy physics and geophysical exploration (ref. Knoll).
https://web.stanford.edu › scintillators
What are scintillator materials? - Stanford: Advanced Optical Ceramics Laboratory
2. I drop a ball from the 13.5 meter tall roof of this building. How much time will it take before it
hits the ground?
Answer:I don’t know
Explanation:
When a 2.50 - kg object is hung vertically on a certain light spring described by Hooke’s law, the
spring stretches 2.76 cm. (a) What is the force constant of the spring? (b) If the 2.50 - kg object is
removed, how far will the spring stretch if a 1.25 - kg block is hung on it? (c) How much work must
an external agent do to stretch the same spring 8.00 cm from its unstretched position?
The work done in the spring is calculated to be 2.8 J
What is Hooke's law?Hooke's law states that, the extension of a given material is directly proportional to the applied force as long as the elastic limit is not exceeded . First, we must bear in mind that the material must remain within the elastic limit for us to apply the Hooke's law in solving the problem.
Now;
From Hooke's law;
F = Ke
F = force applied
K = force constant
e = extension
F = W = mg = 2.50 - kg * 9.8 m/s^2 = 24.5 N
K = 24.5 N/ 2.76 * 10^-2
K = 888 N/m
e = F/K
F = W = 1.25 - kg * 9.8 m/s^2 = 12.25 N
e = 12.25 N/ 888 N/m = 0.014 m or 1.4 cm
Work done by an external agent = 1/2 Kx^2
= 0.5 * 888 * (8 * 10^-2)^2
= 2.8 J
Learn more about Hoke's law:https://brainly.com/question/13348278
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