Answer:
33,333.3J/s
Explanation:
Energy expended which is the work done in Joule
=250,000J
Time taken to expend the energy =7.5s
Power =Unknown
Formula
Power = Work
Time
Hence, Power = 250,000J
7.5s
Power = 33,333.3J/s
A bear slides down an incline which is oriented at 17 degrees above horizontal. What is the coefficient of friction between the bear and the incline if the bear moves with a constant velocity?
[tex]\mu = 0.306[/tex]
Explanation:
Assume that the direction down the incline is the +x-direction. We can apply Newton's 2nd law along the x-axis as
[tex]x:\:\:\:\:\:mg\sin17° - f_s = ma[/tex]
[tex]\Rightarrow mg\sin17° - \mu N = 0[/tex]
where m is the mass of the bear and g is the acceleration due to gravity and acceleration a is zero since the bear is moving with a constant velocity. Along the y-axis, we can write Newton's 2nd law as
[tex]y:\:\:\:\:\:N - mg\cos17° = 0 \Rightarrow N = mg\cos17°[/tex]
Combining these two equations together, we get
[tex]mg\sin17° = \mu(mg\cos17°)[/tex]
Solving for [tex]\mu, [/tex]
[tex]\mu = \dfrac{\sin17°}{\cos17°} = \tan17° = 0.306[/tex]
If a car travels 10 min 2 seconds, what is its speed?
A. 5 m/s
B. 0.2 m/s
C. 20 m/s
D. 2 m/s
The figure shows the light intensity on a screen behind a double slit. The slit spacing is 0.22 mm and the screen is 2.0 m behind the slits (Figure 1). What is the wavelength of the light?
The wavelength of the light is 550 nm
For a double slit interference pattern with slit spacing, d we have
dsinθ = mλ where d = slit spacing = 0.22 mm = 0.22 × 10⁻³ m, m = number of maximum fringe = 2(from the picture) and λ = wavelength of light.
Thus sinθ = mλ/d
Also, tanθ = L/D where L = distance between central maximum and fringe = 2.0 cm/2 = 1.0 cm = 1 × 10⁻² m and D = distance between slit and screen = 2.0 m
Since θ is small, sinθ ≅ tanθ
So, mλ/d = L/D
Making λ subject of the formula, we have
λ = dL/mD
Substituting the values of the variables into the equation, we have
λ = dL/mD
λ = 0.22 × 10⁻³ m × 1 × 10⁻² m/(2 × 2.0 m)
λ = 0.22 × 10⁻⁵ m²/4.0 m
λ = 0.055 × 10⁻⁵ m
λ = 0.55 × 10⁻⁶ m
λ = 550 × 10⁻⁹ m
λ = 550 nm
So, the wavelength of the light is 550 nm
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True or false. The buildings in cities are getting larger
Answer:
trueExplanation:
cuase the city is getting more people than beforeWhat does it mean that " memory is organized in semantic
networks
Answer:
Semantic memory is a category of long-term memory that involves the recollection of ideas, concepts and facts commonly regarded as general knowledge. Examples of semantic memory include factual information such as grammar and algebra.
only question 7. I keep getting it wrong and i’m not sure
Answer:
I think you just have to input the horizontal velocity component.
Explanation:
Assuming no air resistance
The horizontal velocity is constant at
vx = 17.5cos71 = 5.6974... = 5.70 i m/s
The vertical velocity varies with gravity
vy = 17.5sin71 + -9.81(22) = -199.273... = -199 j m/s
v = 5.70i - 199j m/s
arguably one should round to only two significant digits
PLEASE HELP!!!
If a 40cm rope with a 220g bob can hold a maximum tension of 3N
a) what are the maximum angular velocity and inclination angle it can reach before the rope break?
b) Angle of inclination
Answer:
ω = 3.1 rad/s
θ = 36° from vertical
Explanation:
I will ASSUME that the bob and string is acting as a pendulum.
Please understand that the string will break when the bob is at the lowest point of the swing where the vectors of gravity and centripetal acceleration align. It will NOT break at the angle of maximum inclination measured from vertical. This angle is only a component of the maximum potential energy that gets converted to maximum kinetic energy at the lowest point of the swing.
At the bottom of the swing, the string must support the weight of the bob plus supply the required centripetal acceleration.
F = mg + mω²R
F/m = g + ω²R
F/m - g = ω²R
ω = √((F/m - g)/R)
ω = √((3/0.220 - 9.8)/0.40)
ω = 3.09691...
ω = 3.1 rad/s
Potential energy will convert to kinetic energy
mgh = ½mv²
h = v²/2g
R - Rcosθ = v²/2g
R(1 - cosθ) = v²/2g
1 - cosθ = v²/2gR
cosθ = 1 - v²/2gR
cosθ = 1 - (Rω)²/2gR
cosθ = 1 - Rω²/2g
cosθ = 1 - 0.40(3.1²)/(2(9.8))
cosθ = 0.804267
θ = 36.46045...
θ = 36°
7 A 0.25 kg block oscillates on the end of a spring with a spring constant of 100 N/m. If the oscillation is started by elongating the spring 0.1m and giving the block a speed of 3 mis then the amplitude of the oscillation is:
For each of the following measurements give an example of one thing that you might measure with it and why:
Example: square centimeter – the lid of a small box to find its area
A. kilogram
B. meter
C. milliliter
D. square meter
Answer:
i think its d or b but mostly i prefer d
Explanation:
HELP PLS! :/
A ball thrown straight up takes 1.89s to reach a height of 41.6m.
Taking g =9.81 m/s2 the balls initial speed was:
Help plsss
Explanation:
formula: Vi = Vf - (at)
Vi: intial velocity
Vf: final velocity
a: acceleration
t: time
fill in formula with the numbers you are given
Vi= 41.6m - ((9.81 m/s^2)(1.89s))
parenthesis first according to pemdas
Vi= 41.6m - 18.54m/s
Answer: 23.06m/s
disclaimer: I havent done physics in awhile so I have no idea if this is right. just an attempt to help steer you in the right direction hopefully. good luck
How can gravity's role in tectonic plate motion be described?
Answer: In ridge push, the mantle wells upward because of the convection and elevates the edges of spreading oceanic plates. Because these plates are higher at the spreading center, they are forced downhill due to gravity and eventually flatten out to the ocean floor.
the answer I need points for my math test
An airplane has a mass of 33,000 kg and takes off under the influence of a constant net force of 44,000 N. What is the net force that acts on the plane's 70 kg pilot
Answer:
Explanation:
acceleration a = F/m = 44000/33000 = 1.3m/s²
F = ma = 70(1.3) = 93 N
Please write a paragraph explaining the bible verse below in your own words.
Exodus 16:1-3
Answer: Moses
Explanation: The Israelites are angry at Aaron and Moses, because they lead them into this desert where there is no food, or water. It was told that after the Israelites left Egypt they would wander the desert for forty years. The Israelites complain that they would have had plenty of food if they had just stayed enslaved in Egypt. They are not grateful that God has liberated them from slavery.
What is metamarket ?
Answer:
metamarket (plural metamarkets) A group of businesses that offer products that are related from a consumer's perspective but which have no institutional connections. quotations . A market that trades in the medium of exchange of a lower-level market, such as money, derivatives, or credit. quotations.
Explanation:
The best examples of Meta Marketing can be selling family planning ideas or the idea of prohibition. ... Let's say a car selling in a Meta market would be a website, that sells cars but you will also find car parts there, add-ons for cars, colours for cars, mechanic's reviews, etc.
A 770-kg two-stage rocket is traveling at a speed of 6.90×103 m/s away from Earth when a predesigned explosion separates the rocket into two sections of equal mass that then move with a speed of 2.60×103 m/s relative to each other along the original line of motion.What is the speed of each section (relative to Earth) after the explosion?How much energy was supplied by the explosion?
Answer:
Explanation:
Let's just have our reference frame travel along with the original un broken mass. This way the original velocity is not relevant.
Each half will have a mass of 770/2 = 385 kg
Each half will have the same magnitude of velocity (conservation of momentum) which will be 2.6 x 10³/2 = 1.30 x 10³ m/s
Now add back the reference frame velocity to get velocity relative to earth.
Section one will have velocity 6.90 x 10³ + 1.30 x 10³ = 8.2 x 10³ m/s
Section two will have velocity 6.90 x 10³ - 1.30 x 10³ = 5.6 x 10³ m/s
In the moving reference frame, each half will have kinetic energy which could only come from the explosion
KE = ½(385)(1.3 x 10³)² = 325,325,000 J
2(325,325,000) = 650,650,000 J released in the explosion.
Rounding to the three significant figures of the problem numerals
E = 6.50 x 10⁸ J or 650 MJ released
i need help guys please how to do it
Please help if u can thanksss
Answer:
yes its okay i think so it is the correct answer
How long does Sun remain in one zodiac?
(A) 1 year (B) 1 month (C) 1 week (D) 1 day
Answer: (B) 1 month
Brainliest if correct pls!The refractive index of water with respect to air is 5/3 and that of glass is 3/2.What is the refractive index glass with respect to water?
Answer:
9/8
Explanation:
What hero means to me is when a person will do good things for others, no matter how bad it is for them. Also to me a hero is someone who doesn’t follow his pride or show himself good while sabotaging others.
I do not think Cesar Chavez is a hero because he did stand up for gay pride. I did like how he stood up for farmers, but a big no on gay pride. God gave us the gender we are supposed to be. People who turn gay turn against God. Men are supposed to stay Men and Women are supposed to stay Women. That is why I don’t think Chavez is a hero, because he stood up for the gay pride. I know it is what they want to be but not everything is meant to be changed.
I do not think Roberto Clemente is a hero, according to WTAE-TV Pittsburgh he did more to the fans than to the other people. I have realized that he died in a plane crash going to South Africa to help people, but he did not help the other people before his death than he did to his fans.
I do not think Jackie Robinson is a hero because he did not do much to help the citizens. He did help the Dodgers by a lot and went through a tough childhood but I do not think that he is a hero. He is encouraging though because he went through a lot of hate but he didn’t help out other people than the Dodgers.
I do think Hellen Keller is a hero because she did help people a lot. She fought for the rights of women and the rights for people with disabilities which sounds pretty awesome to me. She has also been inspirational for a very long time. Even now!
Answer:
good job my boy this is the right answer
Explanation:
What advantage is there in measuring your distance from I1 to I1' and dividing by 2 rather than measuring the distance OI1 directly
Measuring the distance from [tex]I_1 \ to \ I_1'[/tex] and dividing by 2 has advantage of achieving a more accurate result compared to measurement taking directly.
Measuring the distance from [tex]I_1 \ to \ I_1'[/tex] is equivalent to the double of the distance.
This method of measurement gives a more accurate result because it minimizes error that may result from taking readings form the intervals. It ensures more accurate result compared to the measurement obtained when [tex]OI_1[/tex] is measured directly.
[tex]OI_1 = \frac{I_1 + I_1'}{2}[/tex]
Thus, we can conclude that measuring the distance from [tex]I_1 \ to \ I_1'[/tex] and dividing by 2 has advantage of achieving a more accurate result compared to measurement taking directly.
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PLEASE PLEASE HELP!!
An arrow is shot straight up in the air from the ground with an initial velocity of 54.0 m/s. If on striking the ground it
embeds itself 15.0 cm into the ground, what is the acceleration required to stop the arrow when it hits the ground?
Answer:
you have patience the distance.
Explanation:
the train leaves at 6.30.
A car drives at a constant speed of 45km in 20mn. The speed of the car is..?
Answer:
83.8851 mi/h
The use of non-renewable energy resources in the UK has changed in the last 30 years.
Explain how the use of energy resources has changed in the last 30 years.
Answer: Varies
Explanation: It became more relied upon, technology is responsible for this.
100 POINTS PLEASE HELP You push on a box with 50N to the right, your friend decides to be difficult and pushes against you with 15N. There is also friction between the box and ground that is making your job harder. The friction is 6N in total and the box has a mass of 8kg 1. Draw a free body diagram and put in the essay box using the insert media button 2. Find acceleration of the box 3. bonus - what is the coefficient of friction between the box and the ground
Friction is a force that opposes the relative motion of two surfaces in contact. It exists when the surfaces of two bodies are in contact.The answers to the given questions are:
1. See attachment to this answer
2. a = 3.63 m/[tex]s^{2}[/tex]
3. μ = 0.36
Friction is an oppositional force between the surfaces of two bodies in contact, and tries to limit the motion of one body over the other. It is dependent on the nature of the surfaces in contact.
From the given question;
1. The free body diagram for this question is herewith attached to this answer.
Given that: [tex]F_{1}[/tex] = 50 N, [tex]F_{2}[/tex] = 15 N, [tex]F_{3}[/tex] = 6 N, and m = 8 kg.
2. The acceleration of the body can be determined by:
F = ma
where F is the total force acting on the body, m is the mass of the body and a is its acceleration.
So that;
a = [tex]\frac{F}{m}[/tex]
The total force on the body is;
F = [tex]F_{1}[/tex] - ([tex]F_{2}[/tex] + [tex]F_{3}[/tex])
= 50 - (15 + 6)
= 50 - 21
F = 29 N
Then;
a = [tex]\frac{29}{8}[/tex]
= 3.625
a = 3.63 m/[tex]s^{2}[/tex]
The acceleration of the body is 3.63 m/[tex]s^{2}[/tex].
3. The coefficient of limiting friction (μ) between the surfaces is:
μ = [tex]\frac{Force}{Reaction}[/tex]
Force = 29 N
Reaction = mg
= 8 x 10
= 80 N
μ = [tex]\frac{29}{80}[/tex]
= 0.3625
μ = 0.36
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Answer:
Friction is a force that opposes the relative motion of two surfaces in contact. It exists when the surfaces of two bodies are in contact.The answers to the given questions are:
1. See attachment to this answer
2. a = 3.63 m/
3. μ = 0.36
Explanation:
50 points help
Column I Column II
______ 1. acceleration a. change in distance over time
______ 2. speed b. time interval
______ 3. velocity c. scalar
______ 4. Δt. d. change in position
______ 5. Magnitude only e. change in velocity over time
______ 6. Δx f. change in displacement over time
[tex]\\ \sf\longmapsto Acceleration\longrightarrow Change\:in\: Velocity\:over\:time[/tex]
[tex]\\ \sf\longmapsto Speed\longrightarrow Change\:in\: Distance\:over\:Time[/tex]
[tex]\\ \sf\longmapsto Velocity\longrightarrow Change\:in\: Displacement\: over\:time[/tex]
[tex]\\ \sf\longmapsto ∆t\longrightarrow Time\: interval [/tex]
[tex]\\ \sf\longmapsto Magnitude\:only\longrightarrow Scaler[/tex]
[tex]\\ \sf\longmapsto ∆x=Change\:in\: position [/tex]
An astronaut travels to a star system 6.5 ly away at a speed of 0.80c . Assume that the time needed to accelerate and decelerate is negligible.How much time elapses in earth between the launch and the arrival of the first radio message from the astronaut saying that she has arrived? please 911
Answer:
14.625 years
Explanation:
Because acceleration/deceleration are negligent we can simplify this problem into 2 basic parts:
First: how long before the astronaut arrives? Since the speed of the craft is 0.8 times the speed of light and the distance to travel is 6.5 light-years, the equation to answer this part is:
0.8t=6.5
solve for t by dividing by 0.8
t=6.5/0.8 or 8.125
so, she will arrive in 8.125 years.
Then, once she sends her message, it will travel towards earth at 1 times the speed of light or:
1.0t=6.5 which is just t=6.5
so, her message will arrive back to Earth (8.125+6.5) 14.625 years after takeoff.
The time elapsed in earth will be 14.625 years.
To understand this we need to find how much time she took to travel 6.5 light years and then how much time the signal took to reach the earth.
How much time she took to travel 6.5 light year?0.8t = 6.5 ( because 1 light year = distance travelled by light in a year)
t = 6.5/0.8
t = 8.125 years
So, she travelled for 8.125 year.
How much time it took for the signal?1.0 t = 6.5 ( because radio signal travells with the same speed of light)
t = 6.5/1.0
t = 6.5 years
Sum of these two gives us how much time elapsed on earth between two mentioned events.So, 8.125 + 6.5 = 14.625 years
So, the time elapsed on earth between the launch and the arrivel of the first radio signal is 14.625 years.
#SPJ2
Why are theories excepted as true
Answer:
A theory not only explains known facts; it also allows scientists to make predictions of what they should observe if a theory is true. Scientific theories are testable. New evidence should be compatible with a theory. If it isn't, the theory is refined or rejected.
Explanation:
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Does the stone remain at a constant speed? Or does it speed up?
Answer:
it would remain the same speed
Explanation: the rock isnt going down a hill or anything so therefore if gravity isnt pulling it down a slope then it would remain the same pace
Change 1m2 in to cm2, mm2 and km2
Answer:
1m² = 10000cm²
1m² = 1000000mm²
1m² = 1 × 10^-6
Explanation:
When coverting from square meter to square centimetre, multiply the area value by 10.
When coverting from square meter to millimetre, multiply the area value by 10⁶ ( 1 million )
When converting from meter square to kilometre square, divide the area value by 10^-6 ( 0.000001)
