A car stops in 130 m. If it has an acceleration of -5 m/s2 what was the cars starting velocity?
after
Variables:
Equation and Solve:
Answer:
We are given:
displacement (s) = 130 m
acceleration (a) = -5 m/s²
final velocity (v) = 0 m/s [the cars 'stops' in 130 m]
initial velocity (u) = u m/s
Solving for initial velocity:
From the third equation of motion:
v² - u² = 2as
replacing the variables
(0)² - (u)² = 2(-5)(130)
-u² = -1300
u² = 1300
u = √1300
u = 36 m/s
A boy whirls a ball on a string in a horizontal circle of radius 1 m. How many revolutions per minute must the ball make if its acceleration towards the center of the circle is to have the same magnitude as the acceleration due to gravity
Answer:
Nearest, the revolutions per minute will be 29.
Explanation:
Given that,
Radius of circle = 1 m
Acceleration a =g
We know that,
Angular frequency is defined as,
[tex]\omega=2\pi n[/tex]
Where, n = number of revolutions in one second
We need to calculate the revolutions in one second
Using formula of centripetal acceleration
[tex]a=\omega^2r[/tex]
Put the value of a and ω
[tex]g=(2\pi n)^2r[/tex]
[tex]n=\sqrt{\dfrac{g}{r}}\times\dfrac{1}{2\pi}[/tex]
Put the value into the formula
[tex]n=\sqrt{\dfrac{9.8}{1}}\times\dfrac{1}{2\pi}[/tex]
[tex]n=0.49[/tex]
We need to calculate the revolutions per minute
Using value for the revolutions per minute
[tex]n=0.49\times60[/tex]
[tex]n=29.4[/tex]
Hence, Nearest, the revolutions per minute will be 29.
Weight of a person's muscles, bones, tendons, and ligaments.
A. flexibility
B. lean mass
C. aerobic
What is the function of a landfill
Answer:
A landfill is a carefully designed structure built into or on top of the ground, in which trash is separated from the area around it. Why are landfills important? Landfills contain garbage and serve to prevent contamination between the waste and the surrounding environment, especially groundwater.
Explanation:
Answer: A landfill is a carefully designed structure built into or on top of the ground, in which trash is separated from the area around it. Why are landfills important? Landfills contain garbage and serve to prevent contamination between the waste and the surrounding environment, especially groundwater.
Explanation: Google lol
Experiment 1: A study is done to determine which of two fuel mixtures allows a rocket to travel farther over a period of time. Rocket A, which requires additional equipment to keep it stable, is used to test one fuel mixture, and rocket B is used to test the other. Both rockets are identical aside from their mass. The results indicate that rocket B traveled farther than rocket A over the same period of time. Experiment 2: A double-blind experiment is performed to test whether a new drug is effective in lowering blood pressure. A random sample of subjects with high blood pressure is assigned to two groups. One group receives the new drug and the other group does not. Neither group is permitted to take any other medications during the experiment or to change their lifestyles in any way. The results of the experiment show that the drug is effective in lowering blood pressure.
Identify the experiment in which confounding occurs and the reason for its occurrence.
a. Neither experiment has a confounding variable.
b. Experiment 1 has a confounding variable related to the fuel mixtures. Varying the fuel mixture could skew the results of the study and should be kept constant.
c. Experiment 2 has a confounding variable related to the type of experiment. A double-blind experiment may increase the risk of the placebo effect and possibly skew the results.
d. Experiment 1 has a confounding variable related to the mass of the rockets. Any variation in mass may cause a discrepancy in the distance traveled.
e. Experiment 2 has a confounding variable related to the subjects used. Choosing a sample of subjects with high blood pressure instead of individuals with different blood pressure levels may confuse the results.
Answer: D
Experiment 1 has a confounding variable related to the mass of the rockets. Any variation in mass may cause a discrepancy in the distance traveled.
This is the answer to the question because:
Both experiments do have a confounding variable.Experiment 1 doesn't have to stay constant.A double-blind experiment will not do anything to the placebo.High blood pressure people will not make the results confusing.The answer has to be the option D. Hope this helps you!
how did the author describe the claws of uwang and salagubang?
Answer:
Describes them as sharp and dangerous.
Explanation:
The author describes the claws of uwang and salagubang as large, sharp, dangerous and scary. This creates a certain suspense in the story, as it leaves the reader apprehensive about the imminent danger that these claws pose to those who know them. However, despite their appearance, the claws are not as deadly as they seem because they can only hurt people who are pinched by them.
I need help with this please
1. What is Ohm"s law?
2. If you placed a negatively charged hairbrush near your hair, what charge would your hair be?
3. You must change a lightbulb and the new lightbulb has a larger resistance. If the voltage of the battery does not change, what happens to the current going through the flashlight?
HELLPPPP
1. Ohm's law shows the relationship between:
voltagecurrentresistanceFormula: voltage = current x resistance
2. The negative charge on the hairbrush will induce a positive charge on your hair. As a result, your hair is going to be attracted to the hairbrush (and repelled by other strands of hair.)
3. V = IR, so if the resistance of the current increases, and the voltage of the current stays the same, there is as a result, going to be less current.
Best of Regards!
What kind of variation is there in the mechanical energy as the cart rolls down the ramp? Does this agree with your prediction? Explain.
Answer:
Em₀ = U = m g h , Em_{f} = K = ½ m v²
Explanation:
When a car is on a ramp it has a certain amount of mechanical energy. At the highest point of the ramp the mechanical energy is fully potential given by
Em₀ = U = m g h
As part of this energy descends down the ramp, part of this energy is transformed into kinetic energy and has one part of each, even though the sum remains the initial energy
Em = K + U = ½ m v² + mg y
y <h
when it reaches the bottom of the ramp it has no height therefore there is no potential energy, all of it has been transformed into kinetic energy
Em_{f} = K = ½ m v²
This energy transformation is in the case that the friction force is zero.
If there is a friction force, it performs work against the low car, it is reflected in an increase in the internal energy (temperature) of the car. In this case the energy in the lower part is less than the initial one by a factor
[tex]W_{nc}[/tex] = - fr L
therefore the numeraire values of the velocity are lower, due to the energy lost by friction.
Why is our (a person's) gravitational pull NOT as strong as the Earth's gravitational pull
on us?
Gravity doesn't act on us
The Earth is closer to us than the Moon
Our mass doesn't change so the pull is really the same
We are much smaller than the Earth.
Answer:With gravity, two things with mass will want to move toward each other. However, we humans don't feel our gravity pulling on another person because it's not very big, but we do all feel the pull of Earth's gravity all the time - we're not all floating in the air, because that would be happening without Earth's gravity!
Explanation:
Which of the filling is a fossil fuel?
Six seconds after starting from rest, a car is moving at 15 m/s. What is the car's
average acceleration?
6 m/s2
0-5 m/s?
5 m/s2
2.5 m/s?
-2.5 m/s?
Answer:
2.5 m/s²
Explanation:
a = ∆v/∆t = (15 m/s)/(6 s) = (15/6) m/s² = 2.5 m/s²
In which region does the ocean get the most sunlight throughout the year?
A. Near the equator
B. Near the poles
C. Northern mid-latitudes
D. Southern mid-latitudes
Answer: a
Explanation:
The ocean near the equator gets the most sunlight throughout the year, therefore the correct option is A.
What is the equator?The Equator is an imaginary line passing through the middle of a globe. It is equidistant from the North Pole and the South Pole, Its is a horizontal line residing at 0 degrees latitude.
Because of the revolving position of the earth in the solar system, The ocean near the equator gets the most sunlight throughout the year, therefore the correct option is A.
Learn more about the equator from here
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Two identical items, object 1 and object 2, are dropped from the top of a 50.0m50.0m building. Object 1 is dropped with an initial velocity of 0m/s0m/s, while object 2 is thrown straight downward with an initial velocity of 13.0m/s13.0m/s. What is the difference in time, in seconds rounded to the nearest tenth, between when the two objects hit the ground
Answer:
Δt = 1.1 s
Explanation:
Given information:
H= 50.0 m
g= 9.8 m/s²
Object 1v₀ = 0[tex]H = \frac{1}{2} * g* t^{2}[/tex]
Solving for t, we get:
t₁= 3.2 s
Object 2v₀ = 13 m/sWe can find the final velocity for the object when it hits the ground, using the following expression:
[tex]v_{f}^{2} - v_{o}^{2} = 2*g*H[/tex]
Solving for vf, we get:
vf = 33.9 m/s
Applying the definition of acceleration, being this acceleration the one due to gravity (g), we can write the following equation:
[tex]v_{f} = v_{o} + g*t[/tex]
(Assuming the downward direction to be positive).
Solving for t, we get:
t₂ = 2.1 s
So the difference in time when both objects hit the ground, it's simply
Δt = t₂ - t₁ = 3.2 s - 2.1 s = 1.1 s
A 10-ohm resistor has a constant current. If 1200 C of charge flow through it in 4 minutes what
is the value of the current?
A. 3.0 A
B 5.0 A
C. 11 A
D. 15 A
E. 20A
Answer:
B 5.0 A .
Explanation:
Hello.
In this case, since we know the charge (1200 C), time (4 min =240 s) and resistance (10Ω) which is actually not needed here, we compute the current as follows:
[tex]I=\frac{Q}{t}[/tex]
Then, for the given data, we obtain:
[tex]I=\frac{1200C}{4min}*\frac{1min}{60s}\\\\I=5A[/tex]
Therefore, answer is B 5.0 A .
Best regards!
. A driver in a car travelling at a speed of 26.82m/s sees a deer in the middle of the road 100m
away. What is the minimum constant acceleration that is necessary for the car to stop?
5:04 PM
10/28/2020
Answer:
-3.60 m/s^2
Explanation:
The steam from a boiling pot of water is
A: conduction
B: Convection
C: radiation
D: Radiant energy
I WILL GIVE BRAINLIEST
In which of the following locations would most likely find parenchyma cells? Leaves roots flowers bark
Answer:
I would guess its leaves
Answer:
Leaves
Explanation:
A pile of bricks of mass M is being raised to the tenth floor of a building of height H = 4y above the ground by a crane that is on top of the building. During the first part of the lift, the crane lifts the bricks a vertical distance h1=3y in a time t1=4T. During the second part of the lift, the crane lifts the bricks a vertical distance h2=y in t2=T. Which of the following correctly relates the power P1 generated by the crane during the first part of the lift to the power P2 generated by the crane during the second part of the lift?
A. P2=4P1
B. P2=43P1
C. P2=P1
D. P2=34P1
E. P2=13P1
Answer:
The correct option is B
Explanation:
From the question we are told that
The mass of the pile is M
The height is H = 4 y
The vertical distance achieve during the first lift is [tex]h_1 = 3 y[/tex]
The time taken is [tex]t_1 = 4T [/tex]
The vertical distance achieve during the second lift is [tex]h_2 = y[/tex]
The time taken is [tex] t_2 = T [/tex]
Generally the velocity of the crane during the first lift is
[tex]v _1 = \frac{h_1}{t_1 }[/tex]
=> [tex]v _1 = \frac{3 y}{4T }[/tex]
Generally the velocity of the crane during the second lift is
[tex]v _2 = \frac{h_2}{t_2 }[/tex]
=> [tex]v _2 = \frac{ y}{T}[/tex]
Generally the power generated by the crane during the first lift is
[tex]P_1 = F_1 * v_1[/tex]
Here [tex]F_1[/tex] is the weight of the brick which is mathematically represented as
[tex]F_1 = M * g [/tex] , g is the acceleration due to gravity
So
[tex]P_1 = Mg * \frac{3y}{4T}[/tex]
Generally the power generated by the crane during the first lift is
[tex]P_1 = F_2 * v_2[/tex]
Here [tex]F_2[/tex] is the weight of the brick which is mathematically represented as
[tex]F_2 = M * g [/tex] , g is the acceleration due to gravity
So
[tex]P_1 = Mg * \frac{y}{T}[/tex]
The ratio of the first power generated to the second power is
[tex]\frac{P_1}{P_2} = \frac{Mg * \frac{3y}{4T} }{ Mg * \frac{y}{T} }[/tex]
=> [tex]\frac{P_1}{P_2} = \frac{3}{4}[/tex]
=> [tex]P_2 = \frac{4}{3} P_1[/tex]
According to Newton's first law, which characteristic of a moving object would remain constant if there were no other
forces acting on it?
O size
c
mass
O shape
O speed
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Different kinds of substances have different properties. Compare and contrast the electrical properties of salts, acid , metals
Answer:
salts do not conduct electricity. unless u try to dissociate its ions,it cannot.
metals are good conductors of electricity.
acids also conduct electricity if you dissociate them into ions.
when hydrogen shares electrons with oxygen the outermost shell of the hydrogen atoms are full with how many electrons? and oxygens valence shell is full with how many electrons? because the valence shells of these atoms are full,the atoms are stable.
Answer:
2 and 8
Explanation:
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A 1870 kg car traveling at 13.5 m/s collides with a 2970 kg car that is initally at rest at a stoplight. The cars stick together and move 1.93 m before friction causes them to stop. Determine the coefficient of kinetic friction between the cars and the road, assuming that the negative acceleration is constant and all wheels on both cars lock at the time of impact.
Answer:
The value is [tex] \mu = 0.72 [/tex]
Explanation:
From the question we are told that
The mass of the first car is [tex]m_1 = 1870\ kg[/tex]
the initial speed of the car is [tex]u = 13.5 \ m/s[/tex]
The mass of the second car is [tex]m_2 = 2970\ kg[/tex]
The distance move by both cars is s = 1.93 m
Generally from the law of momentum conservation
[tex]m_1 * u_1 + m_2 * u_2 = (m_1 + m_2 ) * v_f[/tex]
Here [tex]u_2 = 0[/tex] because the second car is at rest
and [tex]v_f[/tex] is the final velocity of the the two car
So
[tex]1870* 13.5+ 0= ( 1870 + 2970 ) * v_f[/tex]
=> [tex]v_f = 5.22\ m/s[/tex]
Generally from kinematic equation
[tex]v_f^2 = u_2^2 + 2as[/tex]
here a is the deceleration
So
[tex]5.22^2 = 0 + 2 *a * 1.93[/tex]
=> [tex]a = 7.06 \ m/s^2 [/tex]
Generally the frictional force is equal to the force propelling the car , this can be mathematically represented as
[tex]F_f = F[/tex]
Here F is mathematically represented as
[tex]F = (m_1 + m_2) * a[/tex]
[tex]F = (1870 + 2970) * 7.06 [/tex]
[tex]F =34170.4 \ N[/tex]
and
[tex]F_f = \mu * (m_1 + m_2 ) * g[/tex]
[tex]F_f = 47432 * \mu [/tex]
So
[tex] 47432 * \mu = 34170.4 [/tex]
=> [tex] 47432 * \mu = 34170.4 [/tex]
=> [tex] \mu = 0.72 [/tex]
If a net force of 15N is applied to a 3kg box, what is the acceleration of the box?
Group of answer choices
5 m/s2
45 m/s2
0.2 m.s2
18 m/s2
Answer:
5
Explanation:
Bextra in bf x vi d sj by
A marathon is 26 mi and 385 yd long. Estimate how many strides would be required to run a marathon. Assume a reasonable value for the average number of feet/stride.
Answer:
According to the University of Iowa, the average length of a stride is 5ft.
Now, the total distance of the marathon is:
26mi and 385yd.
Let's transform that distance into ft.
1mi = 5280ft
Then:
26mi = 26*5280ft = 137,280ft
1yd = 3ft
then:
385yd = 385*3ft = 1,155ft.
Then the total distance of the marathon, in ft, is:
D = 137,280ft + 1,155ft = 138,435 ft.
Now the average number of strides needed will be equal to the quotient between the total distance of the marathon and the distance traveled in each stride.
N = 138,435ft/5ft = 27,687.
Who is the founding father of modern psychology?
Answer:
Sigmund Freud
Explanation:
Answer:
Wilhelm Wundt
1. A hot air balloon weighing 30 N is tied to the ground by a string to prevent
from floating off the ground. The volume of the balloon is 20 m and the
density of air is 1.3 kgm ?. Find:
a. upthrust acting on the balloon. Take g = 10 ms 2.
b. force exerted by the rope on the balloon?
Answer:
a) FB = 260 [N]
b) FT = 230 [N]
Explanation:
In order to solve this problem we must use a static analysis, since Globe does not move. For a better understanding in solving this problem, a free body diagram with the forces acting on the globe is attached.
The buoyant force acts upward as it causes the balloon to tend to float, the weight of the balloon tends to lower the balloon and the downward tension force does not allow the balloon to float
The buoyant force is defined by the following equation:
FB = Ro*V*g
where:
FB = Buoyant force [N]
Ro = density of the air = 1.3 [kg/m^3]
V = volume of the balloon = 20 [m^3]
g = gravity acceleration = 10 [m/s^2]
FB = 1.3*20*10 = 260 [N]
Now we do a sum of forces equal to zero in the y-axis
FB - 30 - FT = 0
260 - 30 = FT
FT = 230 [N]
Big Bird decided to visit three of his friends. He got in his car and drove to Elmo’s house. It took Big Bird 10 minutes to drive the 5 miles. After visiting with Elmo for 30 minutes, he headed to Bert and Ernie’s house. This drive covered 15 miles and took 20 minutes. After a 25 minute stay, Big Bird headed to Cookie Monster’s house. The Cookie Monster’s house was 10 miles away and it took Big Bird another 15 minutes to get there. Because Cookie Monster wasn’t home, he was only there for 5 minutes. Big Bird then headed home, a trip that was 20 miles away and took him 25 minutes. What was the average speed for Big Bird’s whole trip (include his visiting time)?
Average speed =
(total distance)
divided by
(total time).
That's 28.57 miles per hour.
The average speed of Big Bird is 0.384 miles/minute.
What is average speed?The average speed of a body is the ratio of the total distance travelled and the time taken to travel that distance.
Average speed = total distance travelled/time takenThe total distance travelled = 50 miles
total time taken = 130 minutes
Average speed = 50 miles/130 minutes = 0.384 miles/minute.
Therefore, the average speed of Big Bird is 0.384 miles/minute.
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Research has shown that this type of interview is the most effective in predicting later job
performance.
Answer:
Situational Interview
Explanation:
A situational interview is about as close to the real job as it gets. During this type of interview, candidates may be presented with a visual or audio simulation of a scenario and asked to respond to it. They are asked to analyze a problem and profer suggestions on how they would handle it.
If the candidate has solved similar problems in the past, it will come to the fore.
If they haven't then the best outcome is that it will tell the interviewers how well the candidate is able to solve similar problems.
An example of a Situational Interview question is this:
How would you handle an angry customer who for no justifiable reason has decided to create a problematic scene to disrupt the business?
Because Situational Interviews are about behavioral responses (present, past, and future), they are powerful tools in determining or predicting future job performance. An interviewing technique that is developed using this methodology is called the S.T.A.R.
This is an acronym for Situation, Task, Action, Result.
Situation: the candidate is asked to present a challenging situation that occurred recently. This tests what the candidate sees as a challenging situation.
Task: The candidate based on the situation is asked to identify what they need to do to remedy the problem. This tells the interviewer(s) whether or not the candidate can think up a solution for the problem.
Action: Here they define the actual steps taken to resolve the problem
Result: The candidate against the above is required to give the result gotten
Action and Result tell the interviewer the quality of the candidate's ability to follow through and achieve the intended results. This also judges the quality of execution in terms of cost and time. The candidate with the lowest cost and time and the highest quality of outcome is considered the best.
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