8. A rectangle is measured to be 6.4 +0.2 cm by 8.3 $0.2 cm.
a) Calculate its perimeter in cm
b) Calculate the uncertainty in its perimeter.
Answer:
a) The perimeter of the rectangle is 29.4 centimeters.
b) The uncertainty in its perimeter is 0.8 centimeters.
Explanation:
a) From Geometry we remember that the perimeter of the rectangle ([tex]p[/tex]), measured in centimeters, is represented by the following formula:
[tex]p = 2\cdot (w+l)[/tex] (1)
Where:
[tex]w[/tex] - Width, measured in centimeters.
[tex]l[/tex] - Length, measured in centimeters.
If we know that [tex]w = 6.4\,cm[/tex] and [tex]l = 8.3\,cm[/tex], then the perimeter of the rectangle is:
[tex]p = 2\cdot (6.4\,cm+8.3\,cm)[/tex]
[tex]p = 29.4\,cm[/tex]
The perimeter of the rectangle is 29.4 centimeters.
b) The uncertainty of the perimeter ([tex]\Delta p[/tex]), measured in centimeters, is estimated by differences. That is:
[tex]\Delta p = 2\cdot (\Delta w + \Delta l)[/tex] (2)
Where:
[tex]\Delta w[/tex] - Uncertainty in width, measured in centimeters.
[tex]\Delta l[/tex] - Uncertainty in length, measured in centimeters.
If we know that [tex]\Delta w = 0.2\,cm[/tex] and [tex]\Delta l = 0.2\,cm[/tex], then the uncertainty in perimeter is:
[tex]\Delta p = 2\cdot (0.2\,cm+0.2\,cm)[/tex]
[tex]\Delta p = 0.8\,cm[/tex]
The uncertainty in its perimeter is 0.8 centimeters.
. A crane does 62,500 joules of work to lift a boulder a distance of 25.0 meters. How much did the boulder
weigh? (Hint: The weight of an object is considered to be a force in units of newtons.)
13
Answer:
2500 NExplanation:
The weight of the object can be found by using the formula
[tex]f = \frac{w}{d} \\ [/tex]
w is the workdone
d is the distance
From the question we have
[tex]f = \frac{62500}{25} \\ [/tex]
We have the final answer as
2500 NHope this helps you
A car moves forward up a hill at 12 m/s with a uniform backward acceleration of 1.6 m/s2. What is its displacement after 6 s?
Answer:
The displacement of the car after 6s is 43.2 m
Explanation:
Given;
velocity of the car, v = 12 m/s
acceleration of the car, a = -1.6 m/s² (backward acceleration)
time of motion, t = 6 s
The displacement of the car after 6s is given by the following kinematic equation;
d = ut + ¹/₂at²
d = (12 x 6) + ¹/₂(-1.6)(6)²
d = 72 - 28.8
d = 43.2 m
Therefore, the displacement of the car after 6s is 43.2 m
What is the mass of a table that weighs 441 Newtons?
Answer:
45 kg is the mass of a table that weights 441 newton.
Answer:
45 kg
__________________________________________________________
Explanation:
We are given:
weight of the object = 441 N
Solving for the mass of the object:
We know that the weight of an object is the force applied by gravity to pull it towards the ground. So, we can say that:
Weight = Mg
[where M is the mass of the object and g is the gravitational constant]
replacing the variables with given values
441 = M(9.8) [since g = 9.8 m/s²]
Dividing both sides by 9.8
M = 441 / 9.8
M = 45 kg
Hence, the object has a mass of 45 kg
What is the main reason why the age of the oldest rocks can vary from one part of the continent to another?
Answer:
The options are
A. Older rocks are commonly remitted over huge regions
B. Older rocks have been uplifted and eroded away
C. Large parts of the continent are subducted deep within the mantle
D. Parts of the continent have been added by the accretion of tectonic terraces.
The answer is D. Parts of the continent have been added by the accretion of tectonic terraces.
The major reason why the age of the oldest rocks can vary from one part of the continent to another is that parts of continent have been added by the accretion of tectonic terraces.
A baseball is thrown across the field. The ____________is measured from where the ball is thrown to where landed was 75 feet.
motion
direction
distance
reference point
Answer:
distance i think
Explanation:
If a rock is dropped from the top of a tower at the front of and it takes 3.6 seconds to hit the ground. Calculate the final velocity of the penny in m/s.
Answer:
36 m/s
Explanation:
t = 3.6s
u = 0m/s
a = +g = 10m/s²
v = ?
using,
v = u + at
v = 0 + 10(3.6)
v = 36 m/s
A graph of the carbon dioxide levels in the Earth's atmosphere is shown below. Which of the following is true? A. The level of carbon dioxide in the atmosphere did not change before 1900. B. Carbon dioxide levels in the atmosphere have been dropping steadily since 1750. C. The steepest increase in carbon dioxide levels took place in the 18th century. D. The carbon dioxide levels in the atmosphere began increasing rapidly around 1950.
Answer:
D. The carbon dioxide levels in the atmosphere began increasing rapidly around 1950.
Explanation:
Study Island
The carbon dioxide levels in the atmosphere began increasing rapidly around 1950. Therefore, the correct option is option D.
What is carbon dioxide?One carbon atom is covalently doubly connected to the two oxygen atoms in each of the molecules that make up carbon dioxide. At room temperature, it exists as a gas.
In the atmosphere, carbon dioxide serves as a greenhouse gas because it absorbs infrared radiation despite being transparent to visible light. It has increased from which was before values of 280 ppm to be a gas in the atmosphere in the Stratosphere at 431 parts per thousand, or roughly 0.04% by volume. The carbon dioxide levels in the atmosphere began increasing rapidly around 1950. This statement is true.
Therefore, the correct option is option D.
To know more about carbon dioxide, here:
https://brainly.com/question/9630194
#SPJ3
A spinning ice skater will slow down if she extends her arms away from her body. Which of the following statements explain this phenomenon
A) circular motion is always uniform
B) A centripetal force always points outward
C) Angular momentum is always conserved
D) Centripetal acceleration cannot change
Marking brainliest
Answer:
B, which is why ice skaters often keep their arms close to their body when doing spins and jumps to minimize resistance.
A 25 gram bullet travels at 240 m/s, penetrates into the wooden block and move together with the wooden block with a velocity of 27m/s. What is the mass of the wooden block?
Answer:
m2=0.2kg approx.Explanation:
Step one:
given data
mass of bullet m1=25g= 0.025kg
initial velocity of bullet u1=240m/s
mass of block m2=?
initial velocity of bullet u2 of block=0m/s
final velocity of the system after impact v= 27m/s
Required; the mass of the block m2
Step two:
applying the conservation of linear moment/elastic collision we have
m1u1+m2u2=v(m1+m2)
substituting we have
0.025*240+m2*0=27(0.025+m2)
6=0.675+27m2
6-0.675=27m2
5.325=27m2
divide both sides by 27
m2=5.325/27
m2=0.197
m2=0.2kg approx.
A model of Earth’s water budget shows that the precipitation on oceans is 420,000 km3 and the precipitation on land is 130,000 km3. If the evaporation from land is 90,000 km3, how much is the evaporation from oceans?
Answer:
Evaporation from oceans = 460,000 km³
Explanation:
Given:
Precipitation on oceans = 420,000 km³
Precipitation on land = 130,000 km³
Evaporation from land = 90,000 km³
Find:
Evaporation from oceans
Computation:
Evaporation from oceans = Precipitation on oceans + Precipitation on land - Evaporation from land
Evaporation from oceans = 420,000 km³ + 130,000 km³ - 90,000 km³
Evaporation from oceans = 460,000 km³
Answer:ccccccC
Explanation:okay
Calculate the force of Earth's gravity on a spacecraft 2.00 Earth radii above the Earth's surface if its mass is 1650 kg .
Answer:
F = 1.8 KN
Explanation:
Given that the spacecraft is 2.00 Earth radii above the Earth's surface, the force of Earth's gravity on it can be determined by;
F = [tex]\frac{GMm}{(R + h)^{2} }[/tex]
Where: F is the force, G is the universal gravitation constant, M is the mass of the earth, m is the mass of the spacecraft, and R is the radius of the earth and h is the distance of the spacecraft to the surface of the earth.
G = 6.67 x [tex]10^{-11}[/tex] N[tex]m^{2}[/tex][tex]kg^{-2}[/tex], M = 5.972 x [tex]10^{24}[/tex] kg, m = 1650 kg, R = 6371 km, h = (2.0 x 6371 km) = 12742 km.
Thus,
F = [tex]\frac{6.67*10^{-11}*5.972*10^{24} *1650 }{(6371*10^{3}+12742*10^{3}) ^{2} }[/tex]
= [tex]\frac{6.5725*10^{17} }{(19113000)^{2} }[/tex]
= 1799.17
F = 1.8 KN
The force of the Earth's gravity on the spacecraft is 1.8 KN.
If you are sitting on a stationary bus, which frame of reference might make you think the bus has started moving?
a. A car in the next lane passes the bus.
b A passenger moves to the back of the bus. c The bus driver turns to look through the windshield.
scd None of the above.
Since we are sitting in the bus, our current system is the bus
If any object outside our current system moves, we might think that our system has started moving
We are given the choices:
Passenger moving to the back of the bus: This passenger is moving in our current system. So, his movement will not make us think that the bus is moving
The bus driver turns to look through the windshield: The driver is part of our system and is moving moving within the system. So, we wont think that the bus is moving
A car in the next lane: This car is outside our current system and if it moves, we might think that our current system (the bus) has started moving
Therefore, the movement of a car in the next lane will make us think that the bus is moving
A 4 kg cart has a momentum of 12 kg•m/s. What is the cart's velocity?
Answer:
Option A. 3 m/s
Explanation:
From the question given above, the following data were obtained:
Mass of cart = 4 Kg
Momentum of cart = 12 kg•m/s.
Velocity of cart =?
Momentum is simply defined as the product of mass and velocity. Mathematically, it is expressed as:
Momentum = mass × velocity
Thus, we can obtain the velocity of the cart by using the above equation as illustrated below:
Mass of cart = 4 Kg
Momentum of cart = 12 kg•m/s.
Velocity of cart =?
Momentum = mass × velocity
12 = 4 × velocity
Divide both side by 4
Velocity of cart = 12 / 4
Velocity of cart = 3 m/s
Therefore, the velocity of the cart is 3 m/s
A Ferris wheel with 60 spokes has a diameter of 100 m. It makes one rotation every 60 seconds. Find the speed of the passengers when the Ferris wheel is rotating at this rate.
A. 5.24 m/s
B. 6.23 m/s
C. 7.45 m/s
D. 8.01 m/s
Answer:
v = 5.24 m/s
Explanation:
Given that,
No of spokes of a Ferris wheel = 60
The diameter of a wheel, d = 100 m
Radius, r = 50 m
It makes one rotation every 60 seconds.
We need to find the speed of the passengers when the Ferris wheel is rotating at this rate. Let it is v. It can be calculated as follows :
[tex]v=r\omega\\\\=\dfrac{2\pi r }{T}\\\\=\dfrac{2\pi \times 50 }{60}\\\\v=5.235\ m/s[/tex]
or
v = 5.24 m/s
So, the speed of the passengers is 5.24 m/s. Hence, the correct option is (A).
A uniform metal meter-stick is balanced with a 1.0 kg rock attached to the left end of the stick. If the support is located 0.25 m from the left end, what is the mass of the meter-stick? (Hint: meter-stick is 1 m long). a) 0.6 kg b) 2.0 kg c) 1.0 kg d) 3.0 kg
Answer:
c) 1.0 kg
Explanation:
The mass of the stick will be located at the centre of the metre rule. Since the rock is located 0.25m from the pivot, the mass of the meter rule is also 0.25m to the Right of the support
According to law of moment
Sum of clockwise moment = sum of anti clockwise moments
Clockwise moment = M×0.25(mass of metre rule is M)
CW moment = 0.25M
Anti clockwise moment = 0.25×1
ACW moments = 0.25kgm
Equate;
0.25M = 0.25
M = 0.25/0.25
M = 1.0kg
Hence the mass of the metre rule is 1.0kg
Is a light on potential or kinetic?
its the the first one u said
A cable that weighs 4 lb/ft is used to lift 1000 lb of coal up a mine shaft 700 ft deep. Find the work done.
Answer:
980000ft-lbsExplanation:
Step one:
given data
mass of cable= 4lb/ft
mass of coal= 1000lb
dept of mine= 700ft
Step two:
Required
the work-done to lift the coal and the rope combined
Work-done to lift coal
Wc=1000*700= 700,000 lb-ft
Work-done to lift rope
[tex]Wr=\int\limits^{700} _0 {4(700-y)} \, dx \\\\Wr=4(700y-\frac{1}{2}y^2 )\limits^{700}_0[/tex]
substitute y=700 we have, since y=0 will result to 0
[tex]Wr=4(700*700-\frac{1}{2}*700^2 )\\\\Wr=4(490000-245000)\\\\Wr=4(245000)\\\\Wr=980000ft-lbs[/tex]
a bus with a mass of 5000kg is uniformly acceleration from rest. The net force acting on the bus is
Answer:
50,000N
Explanation:
According to Newton's second law of motion;
Net Force = Mass * acceleration
Given
Mass = 5000kg
Let the acceleration = 10m/s²
Net force = 5000 * 10
Net force = 50,000N
Hence the net force acting on the bus is 50000N
How many significant figures are in 0.0067?
Answer:
2
Explanation:
there are 2 significant figures in there
Two kids are roller skating. Amy, with a mass of 55 kg, is traveling forward at 3 m/s. Jenny, who has a mass of 40 kg, is traveling in the opposite direction at 5 m/s. They crash into each other and hold onto each other so that they move as one mass. How fast are they traveling?
Answer:
-7/19
Explanation:
An electron and a proton have charges of an equal magnitude but opposite sign of 1.60 x 10^-19 C. If the electron and proton in a hydrogen atom are separated by a distance of 4.20 x10^-11 m, what are the magnitude and direction of the electrostatic force exerted on the electron by the proton?
Answer:
i. F = 1.3 x [tex]10^{-7}[/tex] N
ii. The direction of the force of attraction exerted by the proton on the electron is towards the itself (i.e a pull).
Explanation:
Since the given charges are opposite, then the force of attraction is experienced. The force of attraction between the two charges can be determined by:
F = [tex]\frac{kq_{1} q_{2} }{d^{2} }[/tex]
where F is the force, k is the constant, [tex]q_{1}[/tex] is the charge of the electron, [tex]q_{2}[/tex] is the charge on the proton, and d is the distance between them.
So that; k = 9.0 x [tex]10^{9}[/tex] N[tex]m^{2}[/tex][tex]C^{-2}[/tex] , [tex]q_{1}[/tex] = 1.6 x [tex]10^{-19}[/tex] C, [tex]q_{2}[/tex] = 1.6 x
Thus,
F = [tex]\frac{9.0*10^{9}*1.6*10^{-19}*1.6*10^{-19} }{(4.2*10^{-11}) ^{2} }[/tex]
= [tex]\frac{2.304*10^{-28} }{1.764*10^{-21} }[/tex]
= 1.3061 x [tex]10^{-7}[/tex]
F = 1.3 x [tex]10^{-7}[/tex] N
The force between the charges is 1.3 x [tex]10^{-7}[/tex] N.
ii. The direction of the force of attraction exerted by the proton on the electron is towards the itself.
A converging meniscus lens has an index of refraction of 1.55 and radii of curvature for its surfaces of 4.60 cm and 9.20 cm. The concave surface is placed upward and filled with carbon tetrachloride (CCl4), which has n = 1.46. What is the focal length of the CCl4-glass combination?
Answer: the focal length of the CCl4-glass combination is 102.31 cm
Explanation:
Given that;
Index of refraction n1 = 1.55
carbon tetrachloride (CCl4), which has n2 = 1.46
radii of curvature for its surfaces R1 = 4.6cm and R2 = 9.20 cm
the focal length of the CCl4-glass combination = ?
we can determine the focal length using the Formula;
1/f = ( n1 - n2) ( 1/R1 - 1/R)
so we substitute in our values
1/f = ( 1.55 - 1.46 ( 1/4.6 - 1/9.20)
1/f = 0.09 × 0.1086
1/f = 0.009774
f = 1 / 0.009774
f = 102.31 cm
Therefore the focal length of the CCl4-glass combination is 102.31 cm
How does Wind Energy impact the environment? Use in your own words.
Answer:
wind energy can have adverse environmental impacts by, including the potential to reduce, fragment, or degrade habitat for wildlife, fish, and plants.
Answer:
Wind energy is better than fossil fuels in that it dosen't require the extraction of a limited resource or the release of carbon dioxide, but the manufacturing of the turbines uses materials that are harmful to the enviroment and the nonrecyclable turbine blades will inevitably end up in landfils. In conclusion, wind energy has its problems, but it is still better than most of the nonrenewable alternatives.
Explanation:
PLS HELP WILL GIVE BRAINLIST
what is the rate at which an object moves towards a target in
A speed B Arc C force D trajectory
Answer: The rate at which an object moves towards a target is Speed
Explanation:
Rate is something that tells us amount of solmething that changes in one unit of time.
Speed is defined as the measure of the rate of movement of a body expressed either as the distance travelled divided by the time taken.
Arc is defined as the apparent path described above and below the horizon taken up by a celestial body.
Force is defined as a push or pull upon an object resulting from the object's interaction with another object.
Trajectory is defined as the path followed by an object moving under the action of given force.
The magnitude of the Poynting vector of a planar electromagnetic wave has an average value of 0.724 W/m^2. What is the maximum value of the magnetic field in the wave?
a. 77.9 nT
b. 55.1 nT
c. 38.9 nT
d. 108 nT
Answer:
a. 77.9 nT
Explanation:
Given;
average value of the electromagnetic wave, E = 0.724 W/m^2
The average value of a Poynting vector is given by;
[tex]S = \frac{1}{2\mu_o} *E_oB_o\\\\But, E_o = cB_o\\\\S = \frac{1}{2\mu_o} *cB_o^2\\\\cB_o ^2= 2\mu_o S\\\\B_o^2 = \frac{2\mu_o S}{c}\\\\B_o = \sqrt{ \frac{2\mu_o S}{c}} \\\\B_o = \sqrt{ \frac{2(4\pi*10^{-7}) (0.724)}{3*10^8}}\\\\B_o = 7.79*10^{-8} \ T\\\\B_o = 77.9*10^{-9} \ T\\\\B_o = 77.9 \ nT[/tex]
Therefore, the maximum value of the magnetic field in the wave is 77.9 nT.
Answer:
A I think : )
Explanation:
What is the force of gravity for a 12 kg turkey?
Please help asap
Answer: 117.6N
Explanation:
By the second Newton's law, we know that:
F = m*a
F = force
m = mass
a = acceleration
We know that in the surface of the Earth, the gravitational acceleration is g = 9.8m/s^2.
Then we just can input that acceleration in the above equation, and also replace m by 12kg, and find that the force due the gravity is:
F = 12kg*9.8m/s^2 = 117.6N
Calculating the Velocity of a Wave Quick Check What is the speed of a wave that has a frequency of 173 Hz and a wavelength of 2.59 meters? Express your answer to the nearest whole number. m/s I need answers
Answer:
448m/s
Explanation:
The speed of the wave with a given wavelength and frequency can be calculated using the formula:
λ = v/f
Where;
λ = wavelength (m)
v = speed of wave (m/s)
f = frequency of wave (Hz)
In this question, λ = 2.59 metres, f = 173 Hz, v = ?
λ = v/f
v = λ × f
v = 2.59 × 173
v = 448.07m/s
To the nearest whole number, 448.07 can be written as 448
Hence, the speed of the wave (v) is 448m/s.
Answer:
What is the speed of a wave that has a frequency of 173 Hz and a wavelength of 2.59 meters? Express your answer to the nearest whole number.
448
m/s
Explanation:
How long will it take an object to accelerate from a velocity of 4.8 m/s to a velocity of 15.6 m/s if it is accelerating at a rate of 0.9 m/s2
Initial velocity of the object (u) = 4.8 m/s
Final velocity of the object (v) = 15.6 m/s
Acceleration of the object (a) = 0.9 m/s²
By using equation of motion, we get:
[tex] \bf \longrightarrow v = u + at \\ \\ \rm \longrightarrow 15.6 = 4.8 + 0.9t \\ \\ \rm \longrightarrow 15.6 - 4.8 = 4.8 - 4.8 + 0.9t \\ \\ \rm \longrightarrow 10.8 = 0.9t \\ \\ \rm \longrightarrow 0.9t = 10.8 \\ \\ \rm \longrightarrow \dfrac{0.9}{0.9} t = \dfrac{10.8}{0.9} \\ \\ \rm \longrightarrow t = 12 \: s[/tex]
[tex] \therefore [/tex] Time taken by the object (t) = 12 s
A car is traveling at 21.0 m/s. It slows to a stop at a constant rate over 5.00s. How far does the car travel during those 5.00 seconds before it stops?
Answer:
d = 105 m
Explanation:
Speed of a car, v = 21 m/s
We need to find the distance traveled by the dar during those 5 s before it stops. Let the distance is d. It can be calculated as :
d = v × t
d = 21 m/s × 5 s
d = 105 m
So, it will cover 105 m before it stops.