Answer:
True
Explanation:
The dwarf planet Ceres contains over 50% of the mass of the main asteroid belt.
True
False (if is why)
False
Explanation:
Called an asteroid for many years, Ceres is so much bigger and so different from its rocky neighbors that scientists classified it as a dwarf planet in 2006. Even though Ceres comprises 25 percent of the asteroid belt's total mass, tiny Pluto is still 14 times more massive.
A wall in a house contains a single window. The window consists of a single pane of glass whose area is 0.10 m2 and whose thickness is 8 mm. Treat the wall as a slab of the insulating material Styrofoam whose area and thickness are 11 m2 and 0.15 m, respectively. Heat is lost via conduction through the wall and the window. The temperature difference between the inside and outside is the same for the wall and the window. Of the total heat lost by the wall and the window, what is the percentage lost by the window
Answer:
the percentage of heat lost by the window is 93.18%
Explanation:
Given the data in the question;
Area of glass [tex]A_{glass[/tex] = 0.10 m²
Thickness of glass [tex]t_{glass[/tex] = 8 mm = 0.008 m
Area of Styrofoam [tex]A_{styrofoam[/tex] = 11 m²
Thickness of Styrofoam [tex]t_{styrofoam[/tex] = 0.15 m
we know that;
Thermal conductivity of glass [tex]k_{glass[/tex] = 0.80 J/smC°
Thermal conductivity of Styrofoam [tex]k_{styrofoam[/tex] = 0.010 J/smC°
Now, temperature difference between outside and inside the walls and window is ΔT
So, In time t, heat lost due to conduction in the window will be;
[tex]Q_{glass[/tex] = [[tex]k_{glass[/tex] × [tex]A_{glass[/tex] × ΔTt] / [tex]t_{glass[/tex]
we substitute
[tex]Q_{glass[/tex] = [ 0.80 × 0.10 × (ΔT)t] / 0.008
[tex]Q_{glass[/tex] = [ 0.80 × 0.10 × (ΔT)t] / 0.008
[tex]Q_{glass[/tex] = 10(ΔT)t J
Also, the heat lost due to conduction in the wall be;
[tex]Q_{styrofoam[/tex] = [[tex]k_{styrofoam[/tex] × [tex]A_{styrofoam[/tex] × ΔTt] / [tex]t_{styrofoam[/tex]
we substitute
[tex]Q_{styrofoam[/tex] = [ 0.010 × 11 × ΔTt] / 0.15
[tex]Q_{styrofoam[/tex] = 0.7333(ΔT)t J
Now, Net heat lost in the wall and window is;
Q = [tex]Q_{glass[/tex] + [tex]Q_{styrofoam[/tex]
Q = 10(ΔT)t J + 0.7333(ΔT)t J
Q = 10.7333(ΔT)t J
So, the percentage of heat lost by the windows will be;
% of heat lost = [tex]Q_{glass[/tex] / Q
= 10(ΔT)t J / 10.7333(ΔT)t J
= 0.93167
= ( 0.93167 × 100 )%
= 93.18%
Therefore, the percentage of heat lost by the window is 93.18%
A flat circular coil of wire having 400 turns and diameter 6.0 cm carries a current of 7.0 A. It is placed in a magnetic field of with the plane of the coil making an angle of 30° with the magnetic field. What is the magnitude of the magnetic torque on the coil?
Answer:
6.8 N.m
Explanation:
The computation of the magnitude of the magnetic torque on the coil is given below:
Given that
n = 400
d = 6.0 cm
Current is I = 7.0 A
Angle is [tex]\theta[/tex] = 30 degree
Now
We know that
the magnitude of the magnetic torque is
= nIABsin[tex]\theta[/tex]
= (400) (7.0) π ÷ 4 (0.06m)^2 sin(90° - 30°)
As
[tex]\theta[/tex] = (90° - Ф)
= (400) (7.0) π ÷ 4 (0.06m)^2 sin 60°
= 6.8 N.m
You are asked to design a spring that will give a 1070 kg satellite a speed of 3.75 m/s relative to an orbiting space shuttle. Your spring is to give the satellite a maximum acceleration of 5.00g. The spring's mass, the recoil kinetic energy of the shuttle, and changes in gravitational potential energy will all be negligible.
(a) What must the force constant of the spring be?
(b) What distance must the spring be compressed?
Answer:
[tex]380697.33\ \text{N/m}[/tex]
[tex]0.138\ \text{m}[/tex]
Explanation:
m = Mass rocket = 1070 kg
v = Velocity of rocket = 3.75 m/s
a = Acceleration of rocket = 5g
g = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]
The energy balance of the system is given by
[tex]\dfrac{1}{2}kx^2=\dfrac{1}{2}mv^2\\\Rightarrow kx=\dfrac{mv^2}{x}\\\Rightarrow kx=\dfrac{1070\times 3.75^2}{x}\\\Rightarrow kx=\dfrac{7250}{x}[/tex]
The force balance of the system is given by
[tex]ma=kx\\\Rightarrow m5g=\dfrac{7250}{x}\\\Rightarrow x=\dfrac{7250}{1070\times 5\times 9.81}\\\Rightarrow x=0.138\ \text{m}[/tex]
The distance the spring must be compressed is [tex]0.138\ \text{m}[/tex]
[tex]k=\dfrac{7250}{x^2}\\\Rightarrow k=\dfrac{7250}{0.138^2}\\\Rightarrow k=380697.33\ \text{N/m}[/tex]
The force constant of the spring is [tex]380697.33\ \text{N/m}[/tex].
The plank you are going to walk has a length of 8.76 m and a mass of 16.35 kg. The plank is not bolted down but is to be placed so that 3.17 m of the plank are actually in contact with the boat. The rest of the board overhangs the jelly fish infested waters. You have a mass of 60.3 kg. What is the minimum mass you must put on the end of the board that is still on the ship so that you can successfully walk to the end of the plank without have the board rotate you into the water
Answer:
Explanation:
The center of gravity will act at the middle point that is at 4.38 m from the end of the plank that is on boat . 16.35 x 9.8 N will act at this point .
The plank will turn around a point at 3.17 m from the end of plank that is on boat .
Suppose the weight required be W . It will be placed at the end of the plank that is on boat . The position of man is on the extreme end of the plank that is over water . So its distance from turning point will be 8.76 - 3.17 = 5.59 m .
Taking torque about turning point of all the forces like , weight of plank , weight of the person walking and force due to W
W x 3.17 = 16.35 x ( 4.38 - 3.17 ) + 60.3 x ( 8.76 - 3.17 )
W x 3.17 = 19.78 + 337.07 = 356.85
W = 112.57 kg .
NO LINKS; The graph shows the motion of a train first moving, then stopping, then traveling again at a slower speed. Calculate the average speed for the entire trip.
20 m/s
8.3 m/s
10 m/s
0 m/s
Answer: 0 m/s. that is your answer i hope this help sorry if i am wrong
Explanation:
What does the area under the curve on a velocity-versus-time graph represent? ... then slows down to travel the last 40 miles in three hours. ... 20. A bicyclist travels the first 700 m of a trip at an average speed of 8 m/s, travels the ... to complete the trip at an average speed, for the entire trip of 440 km/h. ... 125) v1= 0 m/s.
A total charge of 9.0 mC passes through a cross-sectional area of a nichrome wire in 3.6s. The number of electrons passing through the cross-sectional area in 10s is
Answer:
n = 1.56 x 10¹⁷ electrons
Explanation:
First of all, we will calculate the current passing through wire:
[tex]I = \frac{q}{t}[/tex]
where,
I = current = ?
q = charge = 9 mC = 0.009 C
t = time = 3.6 s
Therefore,
[tex]I = \frac{0.009\ C}{3.6\ s}\\\\I = 0.0025\ A = 2.5\ mA[/tex]
Now, for the same current in 10 s time the charge will be:
q = It = (0.0025 A)(10 s)
q = 0.025 C
Now, the number of electrons can be given as:
[tex]q = ne\\\\n = \frac{q}{e}\\\\[/tex]
where,
n = no. of electrons = ?
q = charge = 0.025 C
e = charge on single electron = 1.6 x 10⁻¹⁹ C
Therefore,
[tex]n = \frac{0.025\ C}{1.6\ x\ 10^{-19}\ C}[/tex]
n = 1.56 x 10¹⁷ electrons
Why does one side of the Moon’s surface always remain much colder than the other side?
A) The colder side of the Moon has a cloud cover over it.
B) The colder side of the Moon is entirely covered with ice.
C) The colder side of the Moon always faces away from the Sun.
D) The colder side of the Moon has many high-altitude mountains.
Answer:
it's C
Explanation:
The colder side of the Moon always faces away from the Sun.
wegut.
c) A body weighs 1.2N on the moon and 120N on
the earth. Calculate the density of the moon,
taking acceleration of free fall as 10ms on the
earth surface and gravitational constant as
6.67 x 10Nm’kg. The radius of the moon is
2740 km.
We/Wm = ge/gm = 120N/1.2N
or
gm = ge/100 = 0.1 m/s^2
density = mass/volume = 3M/(4pir^3)
Re-arranging this equation, we get
M/r^2 = (4/3)×pi×(density)×r
From Newton's universal law of gravitation, the acceleration due to gravity on the moon gm is
gm = G(M/r^2) = G×(4/3)×pi×(density)×r
Solving for density, we get the expression
density = 3gm/(4×pi×G×r)
= 3(0.1)/(4×3.14×6.67×10^-11×2.74×10^6)
= 130.6 kg/m^3
What happens when sulfur reacts with potassium?
O A. Electrons move from the sulfur atoms to the potassium atoms.
B. Electrons become delocalized among the atoms.
O C. Electrons are shared between the potassium atoms and the sulfur
atoms.
O D. Electrons move from the potassium atoms to the sulfur atoms.
Answer: Electrons move from the potassium atoms to the sulfur atoms.
Explanation: 2 K + S ⇒ 2 K^+ + S^2- . Usually metals donor electrons to non-metals
Five lamp, each labbled "6V,3W" are operated at normal brightness. What is the total energy supplied to the lamps in five seconds.
Answer:
E = 75 J
Explanation:
First, we will calculate the total power consumed by the five lamps:
[tex]Total\ Power = P = (5)(Power\ of\ one\ lamp)\\P = (5)(3\ W)\\P = 15\ W[/tex]
Now, the energy supply can be calculated as follows:
[tex]E = Pt[/tex]
where,
E = Energy = ?
t = time = 5 s
Therefore,
E = (15 W)(5 s)
E = 75 J
A soccer ball with mass 0.450 kg is initially moving with speed 2.20 m/s. A soccer player kicks the ball, exerting a constant force of magnitude 38.0 N in the same direction as the ball's motion. Over what distance must her foot be in contact with the ball to increase the ball's speed to 6.00m/s?
Answer:
0.187 m
Explanation:
We'll begin by calculating the acceleration of the ball. This can be obtained as follow:
Mass (m) = 0.450 Kg
Force (F) = 38 N
Acceleration (a) =?
F = m × a
38 = 0.450 × a
Divide both side by 0.450
a = 38 / 0.450
a = 84.44 m/s²
Finally, we shall determine the distance. This can be obtained as follow:
Initial velocity (u) = 2.20 m/s.
Final velocity (v) = 6 m/s
Acceleration (a) = 84.44 m/s²
Distance (s) =?
v² = u² + 2as
6² = 2.2² + (2 × 84.44 × s)
36 = 4.4 + 168.88s
Collect like terms
36 – 4.84 = 168.88s
31.52 = 168.88s
Divide both side by 168.88
s = 31.52 / 168.88
s = 0.187 m
Thus, the distance is 0.187 m
What is the correct calculation for voltage if the resistance is 3 ohms and the current is 4 amps?
3 x 4 = 12 volts
3 + 4 = 7 volts
4= 3 = 1.33 volts
4-3 = 1 volt
Answer:
iek
Explanation:
Answer:
the answer to your questions above is 3 x 4 = 12 volts
Explanation:
Voltage = Current × Resistance
Please help I’ll mark you brainliest
Answer:
Percentage:
Rr = 50% because it's 2/4 (for both or 25% each since you have them separate)
rr = also 50%, because it's also 2/4.
Phenotype:
Rr = heterozygous
rr = "hozygous" recessive
In addition, RR is "hozygous" dominant
Explanation:
They said the hozygous is a swearword LOL.
P Flag question
Matt, shown below, is able to move
the large truck because
Answer:
he has more pushing force than the truck there for pushing it forword.
Explanation:
two 0.5 kg carts, one red and one green, sit about half a meter apart on a low friction track, you push on the red one with the constant force of 4N for 0.17m and then remove your hand. the cart moves 0.33 m on the track and then strikes the green cart. what is the work done by you on the two cart system?
Answer:
The work done by you on the two cart system is 2 N-m
Explanation:
Work done is the product of force and displacement.
W = F * D
Substituting the given values we get -
W =
[tex]4 * (0.17+0.33)\\= 2[/tex]
The work done by you on the two cart system is 2 N-m
how does light travel across the universe to earth?
180 J of work is done when lifting a box up to a shelf that is 3 m high. What is the mass of the box?
Explanation:
Work done= MGH
180=m×10×3
180/30=m
m=6kg
!! How much voltage is needed to generate a current of 20 Amps if a line has a resistance of 10 ohms ? How much power does the appliance from question number one give off ? If the appliance runs for 3 minutes , how much energy is used ? Please help me
Answer:
Power = 4000watts
Energy = 22.22Joules
Explanation:
Power = I²R
I is the current
R is the resistance
t is the time
Given the following
I = 20Amps
R = 10ohms
t = 3miuntes = 180secs
Substitute
P = 20²*10
P = 400*10
P = 4000Watts
Hence the amount of power used is 4000Watts
Energy used = Power/time
Energy used= 4000/180
Energy used = 22.22Joules
The school is 3, 000m meters from the mall. What is the distance in kilometers?
Answer:
3,000 meters = 3 kilometers
Explanation:
Intensity: Radiation of a single frequency reaches the upper atmosphere of the earth with an intensity of 1350 W/m2. What is the maximum value of the electric field associated with this radiation? (c = 3.00 × 108 m/s, μ0 = 4π × 10-7 T ∙ m/A, ε0 = 8.85 × 10-12 C2/N ∙ m2)
Answer:
The right answer is "1010 V/m".
Explanation:
The given values are:
Intensity,
[tex]I=1350 \ W/m^2[/tex]
[tex]c = 3.00\times 108 \ m/s[/tex]
[tex]\mu_0= 4\pi\times 10^{-7} \ T.m/A[/tex]
Now,
The electric field's maximum value will be:
= [tex]\sqrt{2\times u\times c\times I}[/tex]
On substituting the values in the above formula, we get
= [tex]\sqrt{2\times 4\times \pi\times 10^{-7}\times 3\times 10^8\times 1350}[/tex]
= [tex]\sqrt{32400\times 3.14\times 10^{-7}\times 10^8}[/tex]
= [tex]1010 \ V/m[/tex]
The maximum value of the electric field associated with this radiation is :
1010 V/mGiven data :
Intensity ( I ) = 1350 W/m²
C = 3.00 * 10⁸ m/s
The maximum value of the electric field can be calculated using the equation below
[tex]E_{max} = \sqrt{2*u*c*I}[/tex] ----- ( 1 )
where : I = 1350 W/m², μ = 4π * 10⁻⁷, c = 3.00 * 10⁸
Insert values into equation ( 1 )
∴ [tex]E_{max}[/tex] = 1010 V/m.
Hence we can conclude that the maximum value of the electric field is 1010 V/m .
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These steps are followed when using the half-life of carbon-14 to determine
the age of an object that contains carbon. What is the correct order of these
steps?
A. Use the half-life of carbon-14 to determine the number of half-lives
that have passed.
B. Measure the ratio of parent nuclei to daughter nuclei.
C. Use the number of half-lives that have passed to determine the age
of the object.
A. A,B,C
B. A,C,B
0 0
C. B, A,C
D. C, A, B
Answer: a different one is a.b.c
Explanation: still for ape.x
The correct order to determine the age of the an object using carbon-14 is C, A, B. Thus, option D is correct.
What is half life?
The half-life time is defined as the time taken by the radioactive element to reduce one half of its initial value. It is denoted by t(1/2).
To measure the age of an object, a radioactive isotope called carbon-14 is used. The half-life of carbon-14 is 5,730 years. All the objects in the universe consumes carbon in their lifetime and hence, carbon-14 is used to measure the age of the objects.
The process of determining the age of objects using carbon-14 is called Radiocarbon dating. All living organisms consume carbon in means of food and from atmosphere and when the plant and animals dies, the radioactive carbon atoms start decaying.
When it starts decaying, by using Carbon-14 the age of an object is calculated. The age is estimated by measuring the amount of carbon-14 present in the sample and comparing this carbon with the reference Carbon-14 isotope.
The amount of carbon in preserved plants is identified by:
f(t) = 10e {₋ct}
t = time in years when the plant dies( t= 0)
c = the amount of carbon-14 remaining in preserved plants.
The steps include to find the age of an object is :
1. Use the number of half-lives that have passed to determine the age of the object.
2. Use the half-life of carbon-14 to determine the number of half-lives that have passed.
3.Measure the ratio of parent nuclei to daughter nuclei.
Hence, from these steps the age of an object is determined. Therefore the correct solution is D) C, A, B.
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What is the light speed formula?
If ' c ' is the speed of light, then the formula for it is . . .
c = 299,792,458 meters per second
A playground merry-go-round with a radius of 2.0 m and a rotational inertia of 100 kg m2 is rotating at 3.0 rad/s. A child with a mass of 22 kg jumps onto the edge of the merry-go-round, traveling radially inward. What is the new angular speed of the merry-go-round
Answer:
The new angular speed of the merry-go-round = [tex]1.6rad/sec[/tex]
Explanation:
From angular momentum conservation
[tex]Iw_1 = (I + mr^2)w_2\\\\3*100 = (100 + 22*2^2)w_2\\\\300 = (100 + 88)w_2\\\\w_2 = \frac{300}{188}\\\\w_2 = 1.6rad/sec[/tex]
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Please help!!!!!! Motion and Forces
A wave is a disturbance that carries
A. water from one place to another.
B. sound from one place to another.
C. matter from one place to another.
D. energy from one place to another.
Answer:
(D) energy from one place to another
What is the answer to question 4
In order to make it all the way from the opening to the detector, a wave has to travel through air, glass, water, plastic, and vacuum.
-- The siren and the tuning fork are sounds.
-- Sound cannot travel through vacuum.
-- That knocks out choices B, C, and D.
The answer is A.
Note: Making a big exception here. We don't do test questions on Brainly. That would be cheating. Don't let me catch you doing it again.
What is the acceleration of a bicycle that goes from 3 m/s to 1 m/s in 2 seconds?
0.5 m/s2
1.0 m/s2
1.5 m/s2
-1.0 m/s2
Answer:
a=vf - vi/t
vf=final velocity
vi= initial velocity
t=time period
Now The bicycle went from 3ms to 1ms...
1.. It decelerated
2... Since it went from 3 to 1... 1 is the final velocity while 3 is the initial Velocity
Applying the Formula
a= 1-3/2
= -2/2
a= -1ms-²
Option D
A bicycle possesses 1000 units of momentum. what would be the bicycle's momentum if,
A.its velocity is doubled
B. its mass is tripled
The chart lists the masses of four planets.
Planetary Masses
Planet
Mass
Neptune
1.02 x 1026
Uranus
8.68 x 1025
Mars
6.42 x 1023
Venus
4.87 X 1024
According to evidence that supports Einstein's general
theory of relativity, which list shows the planets that
would cause curvature in space-time from the least
amount of curvature to the greatest?
O Mars, Venus, Uranus, Neptune
O Neptune, Uranus, Venus, Mars
O Neptune, Uranus, Mars, Venus
O Venus, Mars, Uranus, Neptune
Answer:
I think it's A
Explanation:
It's definitely not B on edge
The correct option for the given question about Einstein's general
theory of relativity is Option A) Mars, Venus, Uranus, Neptune.
What is the Einstein's general theory of relativity?Albert Einstein established that the rules of physics apply to all non-accelerating observers in his theory of special relativity.He also demonstrated that the speed of light in a vacuum remains constant regardless of the velocity of an observer.The theory may be used to anticipate everything and describes how objects behave in space and time. For instance: that if there are black holes or not, if Gravity can causes light to bend, The way Mercury behaves when it is in orbit and many more interesting things.As a Conclusion, we can state that the planets who would cause curvature in space time from the least amount of curvature to the greatest will be in order Mars, Venus, Uranus, Neptune.
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