Answer:
B. 90km/hr
Explanation:
The formula for finding velocity =
Displacement/time
The displacement of the car has been given to be = 1215 km West
Time it took to go from Dallas to Paso = 13.5 hours
Then velocity = 1215/13.5
= 90
Therefore velocity = 90km/hour
Option B is the correct answer to this question.
Thank you!
h m u i m he ll a b o r e d
Answer:
KITTEEENNSSSSS last one is what i got for critsmas KlikBot Hexagon Special Pack
Explanation:
Which energy source contributes least to global warming?
A. Coal
B. Natural gas
C. Solar
D. Petroleum
Solar energy source contributes least to global warming. Hence option C is correct.
What is renewable and non renewable energy sources ?Renewable energy is a energy from a source that is not exhausted or depleted when used. Solar energy or wind energy are examples of the renewable energy source. as wind and solar power is abundantly present everywhere in the environment, it can not be exhausted after its over use.
Non-renewable energy comes from sources that will be exhausted or will not be replenished after its use. Fossil fuels: coal, petroleum, and natural gas are the examples of the non renewable energy sources . Coal is the main element in fossil fuels.
Solar energy is abundantly available in the entire solar system. It is renewable energy source, it has no bad effect on the environment and global warming.
Hence option C is correct.
To know more about solar energy :
https://brainly.com/question/9704099
#SPJ7.
A car of mass 1000 kg is travelling at 10 m/s. What is its kinetic energy?
Answer:
50,000
Explanation:
kinetic energy=1\2×mv^2
=1\2×1000kg×10×10
=50000
2200 kg semi truck driving down the highway has lost control. The truck rolls across the median and into oncoming traffic. The truck collides with a 2000 kg car that is traveling north at 45 m/s. The two vehicles stick together creating a single wreck that travels south at 15 m/s. what was the initial speed and direction of the semi truck?
Answer:
The semi truck travels at an initial speed of 69.545 meters per second downwards.
Explanation:
In this exercise we see a case of an entirely inellastic collision between the semi truck and the car, which can be described by the following equation derived from Principle of Linear Momentum Conservation: (We assume that velocity oriented northwards is positive)
[tex]m_{S}\cdot v_{S}+m_{C}\cdot v_{C} = (m_{S}+m_{C})\cdot v[/tex] (1)
Where:
[tex]m_{S}[/tex], [tex]m_{C}[/tex] - Masses of the semi truck and the car, measured in kilograms.
[tex]v_{S}[/tex], [tex]v_{C}[/tex] - Initial velocities of the semi truck and the car, measured in meters per second.
[tex]v[/tex] - Final speed of the system after collision, measured in meters per second.
If we know that [tex]m_{S} = 2200\,kg[/tex], [tex]m_{C} = 2000\,kg[/tex], [tex]v_{C} = 45\,\frac{m}{s}[/tex] and [tex]v = -15\,\frac{m}{s}[/tex], then the initial velocity of the semi truck is:
[tex]m_{S}\cdot v_{S} = (m_{S}+m_{C})\cdot v -m_{C}\cdot v_{C}[/tex]
[tex]v_{S} = \frac{(m_{S}+m_{C})\cdot v - m_{C}\cdot v_{C}}{m_{S}}[/tex]
[tex]v_{S} = \left(1+\frac{m_{C}}{m_{S}} \right)\cdot v - \frac{m_{C}}{m_{S}} \cdot v_{C}[/tex]
[tex]v_{S} = v +\frac{m_{C}}{m_{S}}\cdot (v-v_{C})[/tex]
[tex]v_{S} = -15\,\frac{m}{s}+\left(\frac{2000\,kg}{2200\,kg} \right) \cdot \left(-15\,\frac{m}{s}-45\,\frac{m}{s} \right)[/tex]
[tex]v_{S} = -69.545\,\frac{m}{s}[/tex]
The semi truck travels at an initial speed of 69.545 meters per second downwards.
An 69-kg jogger is heading due east at a speed of 1.6 m/s. A 63-kg jogger is heading 14 ° north of east at a speed of 1.5 m/s. Find (a) the magnitude and (b) the direction of the sum of the momenta of the two joggers. Describe the direction as an angle with respect to due east.
Answer:
[tex]P=203.3819375kg.m/s\\P\approx203.4kg.m/s[/tex]
[tex]\theta=6.4541\textdegree North East\\\theta\approx6.5\textdegree North East[/tex]
Explanation:
From the question we are told that
Mass of first jogger [tex]M=69kg[/tex]
Speed[tex]v_1=1.6m/s[/tex]
Direction [tex]d= East[/tex]
Mass of 2nd jogger [tex]M=63kg[/tex]
Speed [tex]v_2=1.5m/s[/tex]
Direction [tex]d= 14\textdegree north[/tex]
Generally equation for momentum along the the horizontal is mathematically given as
[tex]P_x=m_1v_1 +m_2v_2cos\theta[/tex]
[tex]P_x=(69)*(1.6) +(63)*(1.5)cos14[/tex]
[tex]P_x=202.0929461kg.m/s[/tex]
Generally equation for momentum along the the vertical is mathematically given as
[tex]P_y=m_2v_2cos\theta[/tex]
[tex]P_x=22.86161913kgm/s[/tex]
a)Generally the magnitude of momentum is mathematically given by
[tex]P=\sqrt{(P_x)^2+(P_y)^2}[/tex]
[tex]P=\sqrt{(202.0929461)^2+(22.86161913)^2}[/tex]
[tex]P=\sqrt{41364.21249}[/tex]
[tex]P=203.3819375kg.m/s[/tex]
[tex]P\approx203.4kg.m/s[/tex]
b) Generally the angle [tex]\theta[/tex] is mathematically given by
[tex]\theta=tan^-^1\frac{py}{px} \\[/tex]
[tex]\theta=tan^-^1\frac{22.86161913}{202.0929461}[/tex]
[tex]\theta=tan^-^1(0.1131242805)[/tex]
[tex]\theta=6.4541\textdegree North East[/tex]
Metals are good conductors of heat because .
Answer:
They have the highest melting point so that mean that the temperature and the are a conductive to electricity.
Explanation:
What state of matter can easily be compressed (squeezed into a much smaller space)? *
gases
solids
solids, liquids, and gases
liquids
Answer:
gases.
Explanation:
gases have the highest volume. if you compress (increase pressure) a gas, the volume decreases and it will take up less space as a liquid, and if you compress more, the liquid will become a solid.
additionally info: this is generally true, but as you get into more difficult subjects, this rule does not hold. for example, some substances cannot obtain a certain phase of matter when they are a certain temperature and or pressure. but that could be way more out of this questions league.
A ball is thrown with 50J of kinetic energy, it hits a target which moves with 30J of kinetic energy, how much energy goes to the thermal store of the surroundings?
Answer:
The energy that will go will for thermal store of the surroundings is 20 J.
Explanation:
Given;
kinetic of the thrown ball, K.E₁ = 50 J
kinetic energy used to move the target, K.E₂ = 30 J
The excess energy that will go will for thermal store of the surroundings;
ΔK.E = K.E₁ - K.E₂
ΔK.E = 50J - 30J
ΔK.E = 20 J
Therefore, the energy that will go will for thermal store of the surroundings is 20 J.
How high did a worker lift a 25 kg bag of sand if it now has 2940 of gravitational potential energy
Answer:
12 m
Explanation:
From the question given above, the following data were obtained:
Mass (m) of bag = 25 kg
Potential energy (PE) = 2940 J
Height (h) =?
Objects carried to a particular height will always experience an acceleration due to gravity of 9.8 m/s².
With the above in mind, we can obtain the height to which the load is lifted to as shown below:
Mass (m) of bag = 25 kg
Potential energy (PE) = 2940 J
Acceleration due to gravity (g) = 9.8 m/s².
Height (h) =?
PE = mgh
2940 = 25 × 9.8 × h
2940 = 245 × h
Divide both side by 245
h = 2940 / 245
h = 12 m
Therefore, the worker lifts the load to a height of 12 m.
A construction worker pushes a wheelbarrow with a total mass of 50.0 kg. What is the acceleration of the wheelbarrow if the net force on it is 75N? For physical science
Answer:
1.5m/s²
Explanation:
Given parameters:
Mass of the wheelbarrow = 50kg
Net force applied = 75N
Unknown:
Acceleration of the barrow = ?
Solution:
From Newton's second law of motion, we know that:
Force = mass x acceleration
Now insert the parameters and find the acceleration
75 = 50 x acceleration
Acceleration = 1.5m/s²
You blow up a balloon but don't tie it. When you let it go, it flies around the room.
Which of Newton's Laws does the scenario describe?
1st Law
2nd Law
3rd Law
Answer:
3rd law beacuse there a flies
Margaret Mary, Doug , and Kako are at a local amusement park. They see an attraction called the Giant Slide, which is simply a very long and high inclined plane. Visitors at the amusement park climb a long flight of stairs to the top of the 27inclined plane and are given canvas sacks. They sit on the sacks and slide down the plane 70m long. At the time when the three friends walked past the slide, a 135-kg man and a 20-kg boy are each at the top preparing to slide down. "I wonder how much less time it will take the man to slide down than it will take the boy," said Margaret Mary. "I think the boy will take less time," said Doug. "You're both wrong,"said Kako. "They will reach the bottom at the same time."
The question is incomplete. The compete question is :
Margaret Mary, Doug , and Kako are at a local amusement park. They see an attraction called the Giant Slide, which is simply a very long and high inclined plane. Visitors at the amusement park climb a long flight of stairs to the top of the 27inclined plane and are given canvas sacks. They sit on the sacks and slide down the plane 70m long. At the time when the three friends walked past the slide, a 135-kg man and a 20-kg boy are each at the top preparing to slide down. "I wonder how much less time it will take the man to slide down than it will take the boy," said Margaret Mary. "I think the boy will take less time," said Doug. "You're both wrong,"said Kako. "They will reach the bottom at the same time."
If the man and the boy do not take the same amount of time to reach the bottom of the slide, calculate how many seconds of difference there will between the two times.
Solution :
From body sliding down an incline plane, the acceleration is given by, [tex]$a = g \sin \theta$[/tex]
Since the body slides from rest, the initial velocity is, u = 0
Now the equation of motion, we have
v= u + at
or v = 0 +at
or v = at
or [tex]$t=\frac{v}{a}$[/tex] ............(1)
again we have, [tex]$v^2 -u^2 =2as $[/tex]
or [tex]$v = \sqrt{2s g \sin \theta} $[/tex]
Then from equation (1), we have
[tex]$t=\frac{\sqrt{2sg \sin \theta}}{g \sin \theta}$[/tex]
Thus this means that the time of sliding down an inclined plane does not depend on the mass of the body that slides.
Therefore, Kako is correct.
Since the time taken to slide an inclined plane is same for both the man and the boy, there is no difference between their time of sliding.
Question 2 (5 points)
Evidence gathered by studying the composition and movement of distant
galaxies indicates that the universe expanded rapidly from a single small
point. The universe has continued to expand for over 13 billion years.
Which statement is in agreement with the current understanding of the
expanding universe?
A) All matter and energy were contained inside the small point.
B) Matter and energy came from dark areas of the universe and were attracted to the small point.
C) Matter and energy fell into the small point the same way a black hole attracts matter and energy
D) Matter was condensed into a single point until energy was attracted to the matter from dark areas of the universe.
Answer: A) All matter and energy were contained inside the small point.
Explanation: The theory that all matter and energy in the universe expanded from one condensed point (this is called the big bang theory) is the generally accepted explanation of the origins of our universe. Thought increasing amounts of doubt have been cast upon this theory in the last decade.
The driver of a 1.5 x 103 kg car is traveling east at 10 m/s and increases its speed to 30 m/s east over 15 seconds. What was the change in momentum of the car? Kgm/s
Answer:
30,000kgm/s
Explanation:
Change in momentum is expressed as;
Change in momentum = mass × change in velocity
∆M = m∆v
Mass m = 1.5×10³kg = 1500kg
∆v = 30-10 =20m/s
Substitute into the formula
Change in momentum = 1500(20)
Change in momentum = 30,000kgm/s
Help Please! 5 questions for 25 points? seems fair? Thank you!
Answer:
1. where the skater turns and goes back in the opposite direction- point w
2. gravitational force of the object
3. point a
4. the bar representing sphere 4 should be twice as tall as the bar representing sphere 2
5. B; its mass is smaller (?)
yolo
Answer:
ABCDEFGHIJKLMNOPQRSTUVWXYZ
Explanation:
Fig. 2.1 shows a train
Fig. 2.1
The total mass of the train and its passengers is 750000kg. The train is travelling at a speed of 84m/s.
The driver applies the brakes and the train takes 80s to slow down to a speed of 42m/s.
(a) Calculate the impulse applied to the train as it slows down,
impulse =
[3]
(b) Calculate the average resultant force applied to the train as it slows down,
force =
(2)
Answer:
[tex]\mathrm{(a)\:}32,000,000\:\mathrm{Ns},\\\mathrm{(b)\:}390,000\:\mathrm{N}[/tex]
Explanation:
The impulse-momentum theorem states the impulse on an object is equal to the change in momentum of that object. Momentum is given by [tex]p=mv[/tex]. Since mass is constant, the train's change in momentum is:
[tex]\Delta p=m\Delta v=750,000\cdot42=31,500,000=\fbox{$32,000,000\:\mathrm{Ns}$}[/tex](two significant figures).
Impulse is also given as [tex]\Delta p = F\Delta t[/tex], where [tex]F[/tex] is the average force applied and [tex]\Delta t[/tex] is change in time. Since [tex]t[/tex] is given as [tex]80\mathrm{s}[/tex], we have the following equation:
[tex]F\Delta t=\Delta p\\\\F=\frac{\Delta p}{\Delta t},\\\\F=\frac{31,500,000}{80},\\\\F=393,750=\fbox{$390,000\:\mathrm{N}$}[/tex](two significant figures).
Henry designs an experiment to find out why plants without flowers tend to be wind-pollinated and not animal-pollinated. He takes samples from a variety of plants and studies them in the field. He finds that the evidence supports his hypothesis. Which of these was the hypothesis Henry was testing? Choose the correct answer. Nonflowering plants make less pollen than flowering plants. Nonflowering plants lack the structures to attract animal pollinators. Nonflowering plants grow close to the ground and capture fewer pollinators. Nonflowering plants grow close to the ground because they have no pollen grains.
Answer:
option 2
Explanation:
you are very welcom
2. A uniform rod of weight 5N and length 1m is pivoted at a point 20cm from one of its ends. A weight is hung from the other end so that the rod balances horizontally. What is the value of the weight?
Answer:
The weight is 7.5 N
Explanation:
Since the rod is uniform, its weight applies downwards at its middle (i.e 50 cm mark). The diagram attached to this answer shows the appropriate sketch.
Applying the principle of moment to the question, let the weight by represented by W.
Total clockwise moment = Total counterclockwise moment
[tex]F_{1}[/tex] x [tex]d_{1}[/tex] = [tex]F_{2}[/tex] x [tex]d_{2}[/tex]
5 x 0.3 = W x 0.2
1.5 = 0.2 W
W = [tex]\frac{1.5}{0.2}[/tex]
= 7.5 N
The value of the weight is 7.5 N.
If a 1000 kg car is traveling at 3
meters per second, what is its
kinetic energy?
[04.04] Which best describes the current atomic theory?
Why do we charge a capacitor under a DC voltage source only?
A wave has frequency of 50 Hz and a wavelength of 10 m. What is the speed of the wave? Group of answer choices
Explanation:
hehshehebdbajahwwdszsjshshs shsbw
A boat traveling across a river has a resultant velocity of 10 km/h and travels 34 degrees with respect to the shore. A) What is the boats velocity in m/s?
B) What is the velocity of the river in m/s?
Answer:
a) 1.55 m/s
b) 2.3 m/s
Explanation:
We know that the boat travels across the river, if we define the river as the x-axis, then the velocity of the boat is only on the y-axis.
Then we can write the velocity of the boat in still water as:
S = (0, B)
Now, when the boat is on the river, the velocity of the boat will be equal to the velocity of the boat in still water plus the velocity of the river.
The velocity of the river is:
v = (R, 0).
Then the velocity of the boat in that river is:
V' = (0, B) + (R, 0) = (R, B)
Now, we know that the velocity of the boat is 10km/h, and it travels at an angle of 34° with respect to the shore.
We can use the Pythagoreans theorem to write the components of this velocity as:
x-axis component = 10km/h*cos(34°) = 8.29 km/h
y-axis component = 10km/h*sin(34°) = 5.59 km/h
Then the velocity of the boat can be written in components as:
velocity = ( 8.29 km/h, 5.59 km/h)
And we knew that the velocity of the boat was written as (R, B)
Then we must have:
R = 8.29 km/h
B = 5.59 km/h
a) The speed of the boat in m/s:
We know that the speed of the boat is 5.59 km/h.
First, we know that:
1km = 1000m, then:
5.59 km/h = 5.59*(1000m)h = 5,590 m/h
And we know that:
1h = 3600s
Then we can write:
5,590 m/h = 5,590 m/(3600s) = 1.55 m/s
b) The speed of the river in m/s:
We know that the speed of the river is 8.29 km/h
Using the same reasoning as above, we can do the change of units as follows:
8.29 km/h = 8.29 (1000m)/(3600s) = 2.3 m/s
Which of the following statements is TRUE concerning forces?
A. Forces in the same direction are added together
B. Forces in the opposite direction are subtracted from one another
C. An overall net force must be present in order for movement to occur
D. All of the above
Helium ballon containing 5m3 of Gad at a pressure of 30pka is released. If the temperature is constant calculate the volume the balloon would have when the pressure inside the ballon has fallen to 5kpa answer in metres cubed
Answer:
30m³
Explanation:
Calculation for the volume the balloon would have
First step is to calculate the Constant
Constant=30pka*5m³
Constant=150m³
Now let calculate the Volume using this formula
Balloon Volume=Constant/ Pressure
Let plug in the formula
Balloon Volume=150m³/5kpa
Balloon Volume=30m³
Therefore the volume that the balloon would have when the pressure inside the ballon has fallen to 5kpa is 30m³
If you put something like a piece of cardboard between a magnet and an iron nail, the magnet still holds the nail in place, even though the magnet is not touching the nail. Explain how that happens. Use the word induce in your response.
Answer:
A magnet has a field having lines of force around it that moves through the air which is a nonpermeable medium that allows the passage of magnetic field lines of force. The cardboard is a similar nonpermeable medium and the magnetic lines of force pass through to induce magnetism in the iron nail which is a ferromagnetic material that becomes magnetized by the magnetic field from the magnet
The induced magnetism in the iron nails causes the reverse poles to form in the iron with the iron domain's induced north pole pointing in the direction of the south pole of the magnet and vice versa
The iron nail is then attracted to the magnet as like poles attract, thereby holding the iron nail in place with the cardboard in between, without direct contact between the nail and the magnet as the cardboard prevents the magnet from touching the iron nail held in place
Explanation:
A wave that can travel through empty space?
A. electromagnetic wave
B. mechanical wave
C. compressional wave
D. transverse wave
Answer: B. Mechanical Waves
Explanation:
The image shows landforms in Monument Valley, Utah.
Which correctly lists the three features shown in the photo?
folds, strike-slip faults, and anticlines
anticlines, synclines, and folds
synclines, normal faults, and strike-slip faults
normal faults, folds, and anticlines
The correctly lists the three features shown in the photo is folds, strike-slip faults, and anticlines.
What is the difference between folds and failures?Modern folds are those that emerged recently (on the scale of geological periods), that is, in the Tertiary Period (between 65 million and 2.5 million years ago). Faults are geological structures that originate from vertical (top-down) or inclined internal forces.
The transcurrent fault – also called horizontal fault – occurs when there is displacement in the horizontal plane between the two blocks, being more common in zones where two tectonic plates meet, when these also move horizontally.
See more about transcurrent fault at brainly.com/question/2387953
#SPJ2
Answer: folds, strike-slip faults, and anticlines. (A)
Explanation: Got it right on my exam on Edge.
A professional golfer walks at an at an average rate of 4.20 meters per second on the golf course. The amount of time required for her to walk from the tee to the green 622 meters away is
Answer:
T try d add b CD c
Explanation:
Cdgffd
What is your average speed if you walk 2 kilometers in 20minutes
Answer:
12 km/hr
Explanation:
Speed= Distance/Time
Answer:
12km/h
Explanation:
average speed= Distance covered /time taken
average speed=2km/20minutes
=but 1 minutes is 60 seconds
=2km/60minutes
=12km/h