Answer:
7.0 m/s²Explanation:
The acceleration of an object given it's mass and the force acting on it can be found by using the formula
[tex]a = \frac{f}{m} \\ [/tex]
f is the force
m is the mass
We have
[tex]a = \frac{39}{5.6} \\ = 6.964285...[/tex]
We have the final answer as
7.0 m/s²Hope this helps you
Please help... I'm confused on what I represents in terms of solving the total current. Would variable would I be singling out?
Answer:
the researcher say hi for us the best pa the best of us are going out to eat that I can get my money toward a little bit but the best of luck to be at work by then and we will see what the status
True or False? To observe physical properties in matter, the matter must change into a new substance.
A given container of 5.0 kg of water maintains a constant temperature over 24 hours. If its mass doesn't change, what statements would support identifying it as a closed system.
I. Only energy was exchanged with its surroundings.
II. Its mass was constant because the water lost to evaporation was replaced with an equal volume of water.
III. It didn't exchange matter or energy with its environment.
IV. External work was used to maintain its internal energy.
A) III
B) l and III
C) II and IV
D) I and IV
Answer:
D) I and IV
Explanation:
A closed system is the one where mass can not enter or leave the system, while the energy can enter o leave the system.
I. This is true according to the definition. Because only energy can enter or leave a closed system.
II. This is not true. Because mass interaction is not allowed in a closed system.
III. This is false. Because energy exchange is allowed.
IV. True. Because energy exchange is possible.
Therefore the correct option is:
D) I and IV
A magnetic field of 0.27 T exists in the region enclosed by a solenoid that has 599 turns and a diameter of 9.29 cm. Within what period of time must the field be reduced to zero if the average magnitude of the induced emf within the coil during this time interval is to be 12.8 kV
Answer: [tex]8.54\times 10^{-5}\ s[/tex]
Explanation:
Given
The initial magnetic field is [tex]B=0.27\ T[/tex]
No of turns [tex]N=599\ \text{turns}[/tex]
Diameter of the solenoid [tex]d=9.29\ cm[/tex]
Induced EMF [tex]E=12.8\ kV[/tex]
Induced emf is the product of no of turns and rate of change of flux.
[tex]\Rightarrow E=-N\cdot \dfrac{\Delta \phi }{\Delta t}\\\\\Rightarrow E=-N\cdot \dfrac{\Delta (B\cdot A)}{\Delta t}\\\\\Rightarrow E=-NA\cdot \dfrac{\Delta B}{\Delta t}\\\\\text{Insert the values}\\\\\Rightarrow 12.8=-599\times \pi r^2\cdot \dfrac{(0-B)}{\Delta t}\\\\\Rightarrow \Delta t=\dfrac{599\times \pi \times (4.64\times 10^{-2})\times 0.27}{12.8\times 10^3} \\\\\Rightarrow \Delta t=854.71\times 10^{-7}\ s\\\\\text{Taking absolute value}\\\Rightarrow \Delta t=8.54\times 10^{-5}\ s[/tex]
1 point
4. When mass is in kilograms and velocity is in meters per second then
momentum is in kilograms-meters per second.
True
Ο Ο
False
Answer:
true
Explanation:
momentum = kg (m/s)
momentum = mass × velocity
Which planet(s) in the solar system has/have retrograde orbits around the Sun?
A) Uranus
B) Venus and Uranus
C) Earth, Mars, and Saturn
D) Jupiter
Answer:B
Explanation:
is burning trash a physical change or chemical change?
If two hot-air balloons are filled at the same time, but one filled with warm air and one is filled with hot air, which balloon will wise higher?
Please explain thank you! :))
hot air
Explanation: why cause doesn't every hot air balloon run on hot air
a 4 kg block is moving at 12 m/s on a horizontal frictionless surface. a constant force is applied such that the block slows with an acceleration of 3 m/s^2. how much work must this force do to stop the block?
a. -576 J
b. -360 J
c. -288 J
d. 360 J
e. 576 J
The block comes to a rest from 12 m/s with acceleration 3 m/s^2, which is carried out over a distance x such that
(12 m/s)^2 - 0^2 = 2 (3 m/s^2) x
=> x = (12 m/s)^2 / (2 (3 m/s^2)) = 24 m
The force itself has a magnitude F such that
F = (4 kg) (3 m/s^2)
=> F = 12 N
This force is pointing opposite the direction in which the block is moving, so the work it's performing is negative, and the work done is
W = - (12 N) (24 m) = -288 Nm = -288 J
which makes C the answer.
What is the electric field strength 7.50 x 10E-1 meters from a 2.8 x 10 E-3 C charged object?
Answer:hi
Explanation:
Stunt car A and stunt car B are identical cars with the same mass of 47.1 kg. They are both traveling at 89.3 m/s. Stunt car A crashes into a hard concrete wall, whereas stunt car B crashes into a large pile of soft sand. They both come to a complete stop after the impact.
Stunt Car A experiences a ______ over a ______ of time.
Stunt Car B experiences a ______ over a ______ of time.
Because of the force experienced by Stunt Car A, it will sustain ______ damage than Stunt Car B.
Answer:
1) HIGH IMPULSE, SHORT INSTANT
2) SMALL IMPULSE, MORE INSTANT OF TIME
more
Explanation:
Let's propose the solution of this exercise, let's use the relationship between momentum and momentum
I = Δp
F t = m v_f - m v₀
indicates that the carriage stops v_f = 0
F t = - m v₀
Therefore, if the impact time decreases, the force must increase and therefore the damages also
Car A collides with a concrete wall that is rigid, therefore the collision occurs in a very short time, car B collides with area, so the collision time is extended, now we can complete the sentences
1) Stunt Car A experiences a _HIGH IMPULSE_ over a SHORT INSTANT__ of time.
2)Stunt Car B experiences a _SMALL IMPULSE_____ over a _MORE INSTANT__ of time.
3) Because of the force experienced by Stunt Car A, it will sustain __MORE____ damage than Stunt Car B.a
3) more
A planet moves in a circular orbit of radius 4.5x10^15 m with a period of 4
days. What is its velocity?
Answer:
2.6x10^{10}
Explanation:
please do follow me
An electrical insulator is a material that:
A) contains no charge
B) does not allow electrons to flow
C) has more protons than electrons
D) must be a crystal
Answer:
Option B is appropriate for this question
The springs of a 1500 kg car compress 5.00 mm when its 68 kg driver gets into the driver's seat. Part A If the car goes over a bump, what will be the frequency of oscillations
Answer:
the frequency of the oscillation is 1.5 Hz
Explanation:
Given;
mass of the spring, m = 1500 kg
extention of the spring, x = 5 mm = 5 x 10⁻³ m
mass of the driver = 68 kg
The weight of the driver is calculated as;
F = mg
F = 68 x 9.8 = 666.4 N
The spring constant, k, is calculated as;
k = F/m
k = (666.4 N) / (5 x 10⁻³ m)
k = 133,280 N/m
The angular speed of the spring is calculated;
[tex]\omega = \sqrt{\frac{k}{m} } \\\\\omega = \sqrt{\frac{133280}{1500} } = 9.426 \ rad/s[/tex]
The frequency of the oscillation is calculated as;
ω = 2πf
f = ω / 2π
f = (9.426) / (2π)
f = 1.5 Hz
Therefore, the frequency of the oscillation is 1.5 Hz
Could someone please help me with this question?
Answer:
I linked a screen shot. The decimal version of that is:
11.03 (you want to use the positive version since you're working with area)
A person carries a plank of wood 1.9 m long with one hand pushing down on it at one end with a force F1 and the other hand holding it up at 49 cm from the end of the plank with force F2. If the plank has a mass of 14 kg and its center of gravity is at the middle of the plank, what are the magnitudes of the forces F1 and F2? (The distance of 49 cm is measured from the location of F1.)
Solution :
Given :
mass of the plank, m = 14 kg
length of the plank, l = 1.9 m
Distance between [tex]$F_2$[/tex] and the end at which [tex]$F_1$[/tex] is acting, [tex]$r_2$[/tex] = 0.49 m
Torque exerted by the weight of the plank is given by :
[tex]$\tau_w= r_{\perp} \times F$[/tex]
[tex]$=-\frac{1.9}{2} \times 14 \times 9.8$[/tex]
= -130 Nm
The torque exerted by [tex]$F_1$[/tex] is
[tex]$\tau_1= r_{1} \times F_1$[/tex]
[tex]$= 0 \times F_1$[/tex]
= 0
Torque exerted by [tex]$F_2$[/tex] is
[tex]$\tau_2= r_{2} \times F_2$[/tex]
[tex]$= 0.49 \times F_2$[/tex]
[tex]$= 0.49 F_2$[/tex]
Since the system is in equilibrium, the zero rotational acceleration occurs when the net external torque on the system is zero, i.e.
[tex]$\sum \tau = 0$[/tex]
Therefore, we get
[tex]$$\sum \tau= \tau_1+\tau_2+\tau_w[/tex]
[tex]$0= 0+0.49F_2+(-130)$[/tex]
[tex]$F_2=\frac{130}{0.49}$[/tex]
= 265 N (approx)
We know that zero linear acceleration occurs when the net external force is zero on the system to achieve equilibrium, i.e.
[tex]$\sum F = 0$[/tex]
[tex]$\sum F = -F_1+F_2-mg=0$[/tex]
[tex]$F_1=F_2-mg$[/tex]
= 265 - (14 x 9.8)
= 128 N (approx)
For an electrical project in a residence, the electrical engineer had resistors
resistances equal to 300 and 100 to assemble a circuit of an electrical appliance that must be connected 12
hours per day. In order to obtain a chain for optimal operation, he came to the conclusion that the best
configuration would be the one shown in the figure below (consider the middle thread as ideal). Knowing that
kWh value is $ 0.35, what is the amount that must be paid for energy consumption over 1 month (30 days)?
Answer:
$ 0.077
Explanation:
We'll begin by calculating the equivalent resistance of the three 300 Ω resistors connected in series. This can be obtained as follow:
Equivalent resistance of the three 300 Ω (R₃₀₀) = 300 + 300 + 300
= 900 Ω
Next, we shall determine the equivalent resistance of the two 100 Ω resistors connected in series. This can be obtained as follow:
Equivalent resistance of the two 100 Ω (R₁₀₀) = 100 + 100
= 200 Ω
Next, we shall determine the equivalent resistance in the circuit. This can be obtained as follow:
Equivalent resistance of the three 300 Ω (R₃₀₀) = 900 Ω
Equivalent resistance of the two 100 Ω (R₁₀₀) = 200 Ω
Equivalent Resistance (R) =?
R = R₃₀₀ × R₁₀₀ / R₃₀₀ + R₁₀₀ (since they are in parallel connections)
R = 900 × 200 / 900 + 200
R = 163.64 Ω
Next, we shall determine the energy in KWh. This can be obtained as follow:
Voltage (V) = 10 V
Resistance (R) = 163.64 Ω
Time (t) for 30 days = 12 × 30 = 360 h
Energy (E) =?
E = V²t / R
E = 10² × 360 / 163.64
E = 100 × 360 / 163.64
E = 36000 / 163.64
E = 220 Wh
Divide by 1000 to express in KWh
E = 220 Wh / 1000 = 0.22 KWh
Finally, we shall determine the amount paid for 1 month (30 days). This can be obtained as follow:
Cost per KWh = $ 0.35
Energy (E) = 0.22 KWh
Cost for 30 days =?
Cost for 30 days = Energy × Cost per KWh
Cost for 30 days = 0.22 × 0.35
Cost for 30 days = $ 0.077
Therefore, the amount that must be paid for 1 month is $ 0.077
A boat that can travel at 4.60 km/h in still water crosses a river with a current of 1.80 km/h. At what angle must the boat be pointed upstream to travel straight across the river
Answer:
The angle the boat must be pointed upstream is 69⁰
Explanation:
Check the image uploaded for the diagram;
Given;
speed of the boat on still water, = 4.6 km/h
speed of the boat on a river with current, = 1.8 km/h
The angle the boat must be pointed upstream is calculated as follows
[tex]tan(\theta) = \frac{4.6}{1.8} \\\\tan(\theta) = 2.556\\\\\theta = tan^{-1}(2.556)\\\\\theta = 68.63^0\\\\\theta = 69^0[/tex]
A bird is standing on an electric transmission line carrying 3000 A of current. A wire like this has about 3.0 x 10-5 22 of resistance per meter. The bird's feet are 6 cm apart. The bird itself has a resistance of about 4 x 105 12. The bird experiences a potential difference of 0.0054 V. What current goes through the bird?
Answer:
13.5 x 10^-9 A
Explanation:
Yes
the unit of mass"kilogram" is a fundamental unit. why?
Answer:
kilogram is a fundamental unit because it is one of the 7 fundamental units that serve as a building block for derived units.
Explanation:
Fundamental units are used to measure fundamental quantities. They are fundamental units because they serve as a building block for derived units.
7 fundamental quantities and their corresponding units;
Length – meter
Mass – kilogram
Time - seconds
Temperature - Kelvin
Amount of substance - Moles
Electric Current - Ampere
Luminous intensity - Candela
Thus, kilogram is a fundamental unit because it is one of the 7 fundamental units.
12)A black body is heated from 27°C to 127° C. The ratio of their energies of radiations emitted will be
a)3:4
c)27:64
b)9:16
d)81:256
Answer:
[tex]81:256[/tex].
Explanation:
Let [tex]T[/tex] denote the absolute temperature of this object.
Calculate the value of [tex]T[/tex] before and after heating:
[tex]T(\text{before}) = 27 + 273 = 300\; \rm K[/tex].
[tex]T(\text{after}) = 127 + 273 = 400\; \rm K[/tex].
By the Stefan-Boltzmann Law, the energy that this object emits (over all frequencies) would be proportional to [tex]T^4[/tex].
Ratio between the absolute temperature of this object before and after heating:
[tex]\displaystyle \frac{T(\text{before})}{T(\text{after})} = \frac{3}{4}[/tex].
Therefore, by the Stefan-Boltzmann Law, the ratio between the energy that this object emits before and after heating would be:
[tex]\displaystyle \left(\frac{T(\text{before})}{T(\text{after})}\right)^{4} = \left(\frac{3}{4}\right)^{4} = \frac{81}{256}[/tex].
the process where water vapor into the atmosphere is changed back into liquid water
Answer:
Condensation is the process by which water vapor in the air is changed into liquid water. Condensation is crucial to the water cycle because it is responsible for the formation of clouds.
Explanation:
just is
Consider a 30-cm-diameter hemispherical enclosure. The dome is maintained at 600 K, and heat is supplied from the dome at a rate of 65 W while the base surface with an emissivity of 0.55 is maintained at 400 K. Determine the emissivity of the dome.
Answer:
[tex]\epsilon_2=0.098[/tex]
Explanation:
Diameter [tex]d=30cm=0.3m[/tex]
Temperature [tex]T=600k[/tex]
Rate of supply [tex]r=65W[/tex]
Emissivity of base surface [tex]\in_b =0.55[/tex]
Temperature at base [tex]T_b=400k[/tex]
Generally the equation for Area of base surface is mathematically given by
[tex]A_b=\frac{\pi}{4}d^2[/tex]
[tex]A_b=\frac{\pi}{4}0.3^2[/tex]
[tex]A_b=0.0707m^2[/tex]
Generally the equation for Area of Hemispherical dome is mathematically given by
[tex]A_h=\frac{\pi}{2}d^2[/tex]
[tex]A_h=\frac{\pi}{2}0.3^2[/tex]
[tex]A_h=0.1414m^2[/tex]
Since base is a flat surface
[tex]F_{11}+F_{12}=1[/tex]
[tex]F_{11}=0[/tex]
Therefore
[tex]F_{12}=1[/tex]
[tex]A_b=0.0707m^2[/tex]
Generally the equation for Net rate of radiation heat transfer between two surfaces is mathematically given by
[tex]Q_{21}=-Q_{12}[/tex]
[tex]Q_{21}=\frac{\sigma(T_1^4-T_2^4)}{\frac{1-\epsilon}{A_b\epsilon_1} +\frac{1}{A_bF_{12}} +\frac{1-\epsilon_2}{A_h*\epsilon_2} }[/tex]
Where
[tex]\sigma=5.67*10^{-8}[/tex]
Therefore
[tex]65=\frac{(5.67*10^{-8}(400^4-600^4))}{\frac{1-0.55}{0.0707*0.55}+\frac{1}{0.0707}+\frac{1-\epsilon_2}{0.1414*\epsilon_2}}[/tex]
[tex]\epsilon_2=0.098[/tex]
[tex]\epsilon_2 \approx 0.1[/tex]
Therefore the emissivity of the dome is
[tex]\epsilon_2=0.098[/tex]
Activity 4: Caste System - The Hierarchy
Instruction: Label the hierarchy of the caste system. Write your answer on the
space provided.
Two loudspeakers in a plane are 2.0 m apart and in phase with each other. Both emit 700 Hz sound waves into a room where the speed of sound is 341 m/s. A listener stands 5.0 m in front of the loudspeakers and 2.0 m to one side of the center line. Is the interference at this point completely constructive, completely destructive, or in between
Answer:
interference is between destructive and constructive
Explanation:
The interference of two sound waves periodicity in phase by the speakers is
Δr = [tex]\frac{\phi }{2\pi } \ \lambda[/tex]
in this case they indicate that the frequency is f = 700 Hz, the wave speed is
v =λ f
λ = v / f
λ = 341/700
λ = 0.487 m
Let's use the Pythagorean theorem to find the distance that each wave travels
r₁ = [tex]\sqrt{x^2 + y^2}[/tex]
let's measure the distance from speaker 1
r₁ = [tex]\sqrt{5^2 + 1^2}[/tex]
r₁ = 5,099 m
the distance from the second speaker
r₂ = \sqrt{x^2 + y^2}
r₂ = [tex]\sqrt{5^2 +3^2}[/tex]
r₂= 5.831 m
the difference in the way is
Δr = r₂ -r₁
Δr = 5,831 - 5,099
Δr = 0.732 m
[tex]\frac{ \phi }{2\pi }[/tex] = Δr /λ
\frac{ \phi }{2\pi } = 0.732 / 0.487
\frac{ \phi }{2\pi } = 1.50
this is the phase difference this phase difference is approximately
Ф= [tex]\frac{\pi }{2}[/tex] =1.57,
so the interference is between destructive ( Ф = π) and constructive (Ф=2π)
A sphere has a surface uniformly charged with 3.30 C. At what distance from its center is the potential 4.50 MV
Answer:
r = 6.6 x 10³ m = 6600 m
Explanation:
The potential at a distance from a charged sphere can be given as follows:
[tex]V = \frac{kq}{r}\\\\r = \frac{kq}{V}[/tex]
where,
r = distance = ?
k = Colomb Constant = 9 x 10⁹ Nm²/C²
q = charge on sphere = 3.3 C
V = potential = 4.5 MV = 4.5 x 10⁶ V
Therefore,
[tex]r = \frac{(9\ x\ 10^9\ Nm^2/C^2)(3.3\ C)}{4.5\ x\ 10^6\ V}[/tex]
r = 6.6 x 10³ m = 6600 m
PLS HELP!! Our eyes perceive colors because of differences in which of the following properties of light?
Amplitude
Brightness
Wavelength
Source
Answer:
Your answer is wavelength
A child moving at constant velocity carries a 2 N ice-cream cone 1 m across a level surface. What is the net work done on the ice-cream cone?
Answer:
2 Joule
Explanation:
Work=force *dISPLACMENT
2N*1M
2 JOUL
True False: Marke each statement as true or false.
shift
1. Light intensity affects the rate of photosynthesis.
in
2. Energy is required by all organisms for life.
3. The ability of a plant to repair tissue depends on respiration.
4. The gas needed for photosynthesis is carbon dioxide (CO2).
5. Plants only carry on photosynthesis, not respiration.
6. Respiration can occur without photosynthesis.
Answer:
1) true 2) true 3) true 4) true 5) false 6) false
Explanation:
After 60 days, 100g of a certain element has decayed to only 12.5g.
What is the half- life of this element?
А
30 days
B.
8 days
С
20 days
D
5 days
Answer:
8 days
Explanation: