Answer:
[tex]1796.65\ \text{N}[/tex]
Explanation:
g = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]
w = Weight of spracecraft at the surface = [tex]7.2\times10^3\ \text{N}[/tex]
m = Mass of spracecraft
R = Radius of Earth = [tex]6.38\times10^3\ \text{km}[/tex]
h = Elevation = [tex]6.38\times10^3\ \text{km}[/tex]
G = Gravitational constant = [tex]6.674\times 10^{-11}\ \text{Nm}^2/\text{kg}^2[/tex]
M = Mass of Earth = [tex]5.972\times 10^{24}\ \text{kg}[/tex]
[tex]w=mg\\\Rightarrow m=\dfrac{w}{g}\\\Rightarrow m=\dfrac{7.2\times 10^3}{9.81}\\\Rightarrow m=733.94\ \text{kg}[/tex]
From the gravitational law we have
[tex]w'=\dfrac{GMm}{(r+h)^2}\\\Rightarrow w'=\dfrac{6.674\times10^{-11}\times 5.972\times 10^{24}\times 733.94}{(6.38\times10^6+6.38\times10^6)^2}\\\Rightarrow w'=1796.65\ \text{N}[/tex]
The weight of the spacecraft at the given height is [tex]1796.65\ \text{N}[/tex]
which ocean is between North
America and Europe?
A. Pacific Ocean
B. Atlantic Ocean
C. Indian Ocean
D. Southern Ocean
Answer:
B. Atlantic Ocean
Explanation:
I need help plissss..............
1. Describe the components of the reflex arc
An amateur blacksmith wants to cool off a 42kg glowing piece of iron, specific heat 470and decides to toss it into a 5.0 kg iron bucket with 10.0 kg of room temperature(23 C) water in it. To his surprise the water completely evaporates away (meaning once it vaporizes it is no longer part of the system) and after some time he goes to pick up the bucket but finds that the bucket is at 150 C.
Required:
What was the initial temperature of the glowing piece of iron?
Answer:
The right approach is "1479°C".
Explanation:
The given values are:
Mass of iron piece,
[tex]m_p=42 \ kg[/tex]
Mass of iron bucket,
[tex]m_I=5 \ kg[/tex]
Mass of water,
[tex]m_w=10 \ kg[/tex]
Iron's specific heat,
[tex]C_I=470 \ J/Kg^{\circ}C[/tex]
Water's specific heat,
[tex]C_w=4186 \ J/Kg^{\circ}C[/tex]
Initial temperature,
[tex]t_I=23^{\circ}C[/tex]
Final equilibrium temperature,
[tex]T=150^{\circ}C[/tex]
Latent heat,
[tex]L_v=2260\times 10^3 \ J/Kg[/tex]
As we know,
The heat lost by the glowing piece of iron will be equal to the heat gain by the iron bucket as well as water, then
⇒ [tex]m_IC_I \Delta T=m_wC_w(100-23)+m_wL_v+m_bC_I(150-23)[/tex]
On substituting the given values, we get
⇒ [tex]42\times 420\times \Delta T=10\times 4186(100-23)+10(2260\times 10^3)+5\times 420(150-23)[/tex]
⇒ [tex]17640 \Delta T=3.22\times 10^6+2.26\times 10^7+2.667\times 10^5[/tex]
⇒ [tex]\Delta T=\frac{2.60867\times 10^7}{17640}[/tex]
⇒ [tex]\Delta T=1479^{\circ}C[/tex]
Plaskett's binary system consists of two stars that revolve in a circular orbit about a center of mass midway between them. This statement implies that the masses of the two stars are equal (see figure below). Assume the orbital speed of each star is |v with arrow| = 230 km/s and the orbital period of each is 15.5 days. Find the mass M of each star. (For comparison, the mass of our Sun is 1.99 1030 kg.)
Answer:
[tex]1.554\times 10^{32}\ \text{kg}[/tex]
Explanation:
M = Mass of each star
T = Time period = 15.5 days
v = Orbital velocity = 230 km/s
G = Gravitational constant = [tex]6.674\times 10^{-11}\ \text{Nm}^2/\text{kg}^2[/tex]
Radius of orbit is given by
[tex]R=\dfrac{vT}{2\pi}[/tex]
We have the relation
[tex]\dfrac{Mv^2}{R}=\dfrac{GM^2}{(2R)^2}\\\Rightarrow M=\dfrac{4Rv^2}{G}\\\Rightarrow M=\dfrac{4\dfrac{vT}{2\pi}v^2}{G}\\\Rightarrow M=\dfrac{2v^3T}{\pi G}\\\Rightarrow M=\dfrac{2\times 230000^3\times 15.5\times 24\times 60\times 60}{\pi\times 6.674\times 10^{-11}}\\\Rightarrow M=1.554\times 10^{32}\ \text{kg}[/tex]
The mass of each star is [tex]1.554\times 10^{32}\ \text{kg}[/tex]
When a helicopter flies, what
type of energy is it using?
A. Thermal energy
B. Mechanical energy
C. Electromagnetic energy
Answer: B. Mechanical energy
Explanation: "Mechanical energy is the energy that is possessed by an object due to its motion or due to its position. Mechanical energy can be either kinetic energy (energy of motion) or potential energy (stored energy of position)."
"Potential and kinetic energy of an object as it is stored and moved. Examples of MECHANICAL ENERGY- roller coasters, hydraulic lift, bow and arrow, and helicopters. Helicopters, cars, roller coasters, all moving objects that are being acted on by a force."
Incorrect options: A. Thermal energy and B. Electromagnetic energy. (explanation on both below)
"Thermal energy (also called heat energy) is produced when a rise in temperature causes atoms and molecules to move faster and collide with each other. The energy that comes from the temperature of the heated substance is called thermal energy."
"Electromagnetic radiation, in classical physics, the flow of energy at the universal speed of light through free space or through a material medium in the form of the electric and magnetic fields that make up electromagnetic waves such as radio waves, visible light, and gamma rays."
A potter's wheel is a uniform disk of mass 4.50 kg and radius 0.650 m and can spin freely around a vertical axis through its center. With the wheel spinning at an angular speed of 4.70 rad/s, a small piece of clay of mass 0.870 kg is dropped at the outer edge of the wheel and sticks to it. Find the final angular speed of the wheel clay. Treat the piece of clay as a point particle. Group of answer choices
Answer:
3.39 rad / s.
Explanation:
Given data:
mass of disk = 4.50 Kg
radius of wheel = 0.650 m
mass of the clay = 0.870 kg
The moment of inertial of the wheel = I = 4.5 kg x ( 0.65 m )2 / 2 = 0.95 kg . m2.
Now, applying the principle of angular momentum conservation :
Iω_i = ( I + mr2 )ω_f.
where ω_i = initial angular speed= 4.70 rad/s, ω_f = final angular speed
Hence, ω_f = Iω_i / ( I + mr2 )
= ( 0.95 kg . m2 x 4.7 rad / s ) / [ 0.95 kg . m2 + 0.87 kg x ( 0.65 m )2 ]
= 3.39 rad / s.
Hence, correct answer is : 3.39 rad / s.
A graduated beaker with 375 mL of water is sitting on a scale which measures the weight of the glass and water to be 7.60 N. When a rock is put into the glass, the volume level of the water changes to 450 mL and the scale reading changes to 9.22 N. What is the specific gravity of the rock
Answer:
Volume of water displaced = 450 - 375 = 75 ml
Vr = volume of rock = 75 ml
Wr = 9.22 - 7.60 = 1.62 N weight of 75 ml of rock
Density of rock = 1.62 N / 75 ml = .0216 N / ml
Density of water = 1000 g / 1000 ml = 9.8 N / 1000 ml = .0098 N / ml
Density of rock / density of water = .0216 / .0098 = 2.20
The specific gravity of the rock in the given water volume is 0.2.
The given parameters;
initial volume of the water, = 375 mlweight of the water, = 7.6 Nfinal volume of water = 450 mlchange in scale reading = 9.22 NThe specific gravity of the rock is calculated as follows;
[tex]S.G = \frac{weight \ in \ air}{Weight \ in \ water} \\\\S.G = \frac{450 - 375}{375} \\\\S.G = 0.2[/tex]
Thus, the specific gravity of the rock in the given water volume is 0.2.
Learn more here:https://brainly.com/question/19142897
What happens during rusting?
Answer:
when water hits a metal surface it alongside oxygen have a chemical reaction making Hydrogenated Iron Oxide
Explanation:
what i remember from 7th grade
According to the law of reflection, the angle of incidence is equal to the angle of
refraction
reflection
deflection
absorption
Answer:
Reflection
the angle of incidence is equal to angle of reflection
According to the law of reflection, the angle of incidence is equal to the angle of reflection. Hence option B is correct.
What is Reflection ?Reflection is the change of direction of the wave at the interface which separates two media. it get incident on the other media and get return to the same media is called as reflection. Common examples include the reflection of light, sound and water waves.
we can see that in the dark room when we incident light on the mirror, the direction of the light changes at the point of the incidence. in the scientific language we can say that light has reflected from the surface of the mirror. in this case angle of incidence is always equal to angle of reflection.
Any mirror bounce back the incident light. therefore it is used to see our face. it reflects almost all the light to same medium from which light has been incident.
Hence option B is correct.
To know more about reflection :
https://brainly.com/question/30270479
#SPJ7.
Which of the following involves an endothermic reaction
Answer:
A
Explanation:
Photosynthesis requires energy to drive the chemical reaction. Photosynthesis is an endothermic reaction. This means it cannot occur without energy (from the Sun).
What do we call the part of the wave labeled with the letter
D in the image below?
B
MONO
A. Compression
B. Rarefaction
D. Wave speed
C. Frequency
Answer:
C. Frequency..............
HELP ASAP GIVING 5 PTS AND BRAINLIEST
Which of the following is an example of a constructive force that helps to shape Earth's land?
A. When two plates in the Earth's lithosphere collide and cause the land to rise up into a mountain
B. When glaciers break pieces of a mountain away as they slide downward
C. When erosion, due to rain, wind, snow, and ice, wears away a mountain top
The answer is C I believe
A yo-yo is twirled in a horizontal circle on a 2 meter long string at 4 m/s. Calculate the speed of the yo-yo if it has the same rotational speed but only 0.5 meters long.
a potted plant falls from a window sill and is gaining speed. which one of the following statements is true of the plant?
a) its kinetic energy is constant
b) its kinetic energy is increasing
c) its kinetic energy is decreasing
Which of the following represents a concave lens?
A. -di
B. +di
C. -f
D. +f
Answer:
The answer is option D. +f
Option D represents a concave lens. There are two types of lenses, one is a concave lens while the other is the convex lens.
What is the definition of a concave lens?A concave lens deviates a direct beam from the source into a reduced form. At minimum, one interior face of concave lenses is curved.
Because it is curved round inwards at the center and bulges outwards through the edges, causing the light to diverge, a concave lens is also known as a diverging lens.
It forms an upright , virtual picture both real and virtual pictures are formed from the concave lens.
The image formed from the positive side of the focus of the lens.+f shows the positive side of the focus of the lens.f is the focal length.
Hence, option D represents a concave lens
To learn more about the concave lens, refer to the link;
https://brainly.com/question/2919483
#SPJ2
The work-energy theorem states that the work done on an object is equal to a change in which quantity?
kinetic energy
displacement
potential energy
mass
The work-energy theorem states that the net work done by the forces on an object equals the change in its kinetic energy.
Answer:
a kinetic energy
Explanation:
Can someone please help me with this !!!!
Answer:
I'm not sure but I think it's 4.5 v
The diagram below shows the beaks of five species of birds that developed over time from
one parent species. The five species of birds can be found living in the different areas. Which
of the following BEST explains why the beak shape of each species of bird developed
differently? * 5
(1 Point)
A. Birds in different areas were able to make different birdcalls and songs.
O
B. Birds in different areas were exposed to different food sources.
C. Birds in different areas had different materials to make nests.
o o
D. Birds in different areas had different predators to defend or hide from.
Answer:
Birds in different areas were exposed to different food sources.
Explanation:Im almost 100 percent this is it.
Answer:
the answer is B
Explanation:
i did test on preformance
The chemical energy in your food is
transformed into what type of energy in
your moving muscles?
A. Light
B. Mechanical
C. Sound
D. Electromagnetic
Answer:
Electromanetic
Explanation:ESPERO TE AYUDE
to measure the static friction coefficient between a block and a vertical wall, a spring is attached to the block, is pushed on the end in a direction perpendicular to the wall until the block does not slip downward. If the spring is compressed, what is the coefficient of static friction
Answer:
μ = mg/kx
Explanation:
Since the bock does not slip, the frictional force equals the weight of the block. So, F = mg. Now, the frictional force, F = μN where μ = coefficient of static friction and N = Normal force.
Now, the normal force equals the spring force F' = kx where k = spring constant and x = compression of spring.
N = F' = kx
So, F = μN = μkx
μkx = mg
So, μ = mg/kx
A bowl of ice cream is sitting on a table.
Which is NOT conduction?
A. The sunlight streaming through the window melts the
ice cream.
B. The bowl is cold because of the ice cream.
C. The table is cold because of the cold bowl.
Answer: The bowl is cold because of the ice cream
Explanation:
Archimedes' Principle states that a. the velocity of a fluid is directly proportional to the pressure exerted on the fluid. b. the pressure of a fluid is inversely proportional to the temperature of the fluid. c. the pressure in a fluid is directly related to the depth below the surface of the fluid. d. an object immersed in a fluid is buoyed up by a force equal to the weight of the displaced fluid.
Answer:
d. an object immersed in a fluid is buoyed up by a force equal to the weight of the displaced fluid.
What happens after the president gives the budget to Congress?
Answer: The president submits a budget to Congress by the first Monday in February every year. The budget contains estimates of federal government income and spending for the upcoming fiscal year and also recommends funding levels for the federal government.
Explanation:
Answer: The president submits a budget to Congress by the first Monday in February every year. The budget contains estimates of federal government income and spending for the upcoming fiscal year and also recommends funding levels for the federal government.
Your welcome!! :)
can someone help me with science:
The cells within a multicellular organism are of a uniform shape.
True
or False
Answer:
trur
Explanation:
gvidttcyhjddgdhjfjdjsjs
HELP ITS DUE IN 4 MINUTES
Answer:
the nephew
Explanation:
because we need to First find the trails that is on top of all the others in order to find who was the last to leave, since the person that was last to leave would most likely step on another person's trail that has been theirs before them.
by looking at this picture I noticed that the butler's footprint was the latest one but the dogs footprint steps over it therefore making it the last to leave, and the person who owns a dog is her nephew so therefore the nephew is the one that stole the butterfly trophy.
Mrs. Archer spent her Saturday running a bunch of errands. She started out by
traveling 2 km east, then 5 km south, 12 km east, 2 km south then 40 km west, 60
km north. Calculate her displacement on the Y AXIS.
Answer:
Velocity = displacement/time whereas speed is distance/time. use the formula
Explanation:
Which planet is least like earth? Mars,Venus, or Jupiter
Answer:
mars, reason why is because they both are diff from the size
Explanation:
It's your birthday, and to celebrate you're going to make your first bungee jump. You stand on a bridge 100m above a raging river and attach a 35-m-long bungee cord to your harness. A bungee cord, for practical purposes, is just a long spring, and this cord has a spring constant of 43N/m . Assume that your mass is 79kg . After a long hesitation, you dive off the bridge. How far are you above the water when the cord reaches its maximum elongation? h=
Answer:
h = 47 m
Explanation:
First, we will calculate the force on the cord due to the weight:
[tex]Force = F = Weight\\F = mg\\F = (79\ kg)(9.81\ m/s^2)\\F = 775\ N[/tex]
Now, we will calculate the elongation by using Hooke's Law:
[tex]F = k \Delta x[/tex]
where,
k = spring constant = 43 N/m
Δx = elongation = ?
Therefore,
[tex]775\ N = (43\ N/m)\Delta x\\\\\Delta x = \frac{775\ N}{43\ N/m}\\\\\Delta x = 18\ m\\[/tex]
So, the final length of the cord will be:
[tex]Final\ Length = Initial\ Length + \Delta x\\Final\ Length = 35\ m + 18\ m\\Final\ Length = 53\ m\\[/tex]
Hence, the height from water (h) can be found using the following formula:
[tex]h = Height\ of\ Bridge - Final\ Length\ of\ cord\\h = 100\ m - 53\ m\\[/tex]
h = 47 m
A thermionic tube with only a cathode and an anode is called?