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
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.
An object is subject to a 84 Nm torque about a point when a
21 N of force is applied to a second point along the object's
length. How far apart are the two points
Answer:
d = 4[m]
Explanation:
Torque in physics is defined as the product of force by distance. This way you can use the following equation to calculate the torque.
[tex]T=F*d[/tex]
where:
T = torque [N*m]
F = force [N]
d = distance [m]
Now replacing in the equation above.
[tex]84=21*d\\\\d= 4[m][/tex]
Explain why refraction takes place.
Please help explain in a simple way
Answer:
lCdfKFBWRblNLWFNJLBe
Explanation:
jk jk Refraction is an effect that occurs when a light wave, incident at an angle away from the normal, passes a boundary from one medium into another in which there is a change in velocity of the light
Which two life functions of animals help maintain the water cycle by recycling water back into the environment?
Answer:
Respiration and excretion
Explanation:
Respiration. When animals breathe, their lungs release water vapour to the atmosphere.
Animals excrete water by respiration and by passing urine.
At the height of 800 meters, a skydiver falls from an airplane flying horizontally at 40 m/sec. What is the horizontal distance of the skydivers travel before they "hit" the ground?
Answer:
The horizontal distance traveled by the skydiver is 510.8 m.
Explanation:
Given;
height of fall, h = 800 m
initial velocity of the airplane, u = 40 m/s
The time to fall to the ground is calculated as;
[tex]t = \sqrt{\frac{2h}{g} } \\\\t = \sqrt{\frac{2 \times 800}{9.81} }\\\\t = 12.77 \ s[/tex]
The horizontal distance or range of the motion is calculated as;
R = ut
R = 40 m/s x 12.77 s
R = 510.8 m
Therefore, the horizontal distance traveled by the skydiver is 510.8 m.
The Periodic Table Question 4 of 10 If an element forms a 2+ ion, in which group of the periodic table would you expect to find it? D A. 2 B. 17 O C. 1 D. 18 7
Answer:
B is the difference قصدي لا انا اعرف بشير بس ما اعرف اخوه يعني *قصدي لا انا اعرف بشير بس ما اعرف اخوه يعني *قصدي لا انا اعرف بشير بس ما اعرف اخوه يعني *قصدي لا انا اعرف بشير بس ما اعرف اخوه يعني *قصدي لا انا اعرف بشير بس ما اعرف اخوه يعني *
What is a heating curve of water?
Answer:
eye
Explanation:
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
please answerrr asapp tyty Laura goes for cycle from her house to the post office 4km away how long did it take for Laura to reach the post office
Answer:
See the answer below
Explanation:
The time Laura took to reach the post office would depend on the speed of cycling.
We know that;
speed = [tex]\frac{distance}{time}[/tex]
hence,
time = [tex]\frac{distance}{speed}[/tex]
Since the distance from Laura's house to the post office is 4 km, the equation becomes;
time = [tex]\frac{4}{speed}[/tex]
Just ensure that the speed is in km per hour, minute, or seconds in order to obtain the time in hours, minutes, or seconds respectively.
PLEASE HELP ASAP!!!!!
Carrie pulls a 41.5 kg bin across the floor of her garage using a rope that is attached to the bin. She pulls with a force of 138 N, at an angle of 28.0° above horizontal. The coefficient of kinetic friction between the floor and the box is 0.290 . What is the acceleration of the box?
Answer: 0.81N
Explanation: Fwx = .165x 9.81 Silicon 30 = 0.81N
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
Test populations are studied. Population one is found to obey the differential equation dy1/da=o.2y1 and the population two obeys dy2/da = -0.3y2 , where t is the time in years? Which population is growing and which is declining
Answer:
Population 1 indicates growth while Population 2 indicates a declining population
Explanation:
Here, using the given rate of change of the population, we want to determine which of the two is growing and which is declining
From the rate of change of both, we can determine this. Looking at the differential equation for the first one, we can see that it is of positive value. Looking at the differential equation for the second one. we can see it is of negative value
While a positive change rate indicates growth, a negative change rate will indicate otherwise
Hence, we can conclude that the one with a negative rate change will indicate a declining population
A ball of mass 0.3kg, moving at a velocity of 20m/s is suddenly hit by a force of 5N for a time of 0.03 sec. Find its new velocity of motion
Answer:
F * t = m * Δv
F * t = m * (v2 - v1) where v2 is the new velocity and v1 is the current velocity
m * (v2 - v1) = (F * t)
Plugging in the values,
0.3kg * v2 - 0.3kg * 20 m/s = 5 * 0.03 s
0.3 * v2 - 6 = 0.15
0.3 * v2 = 0.15 + 6
v2 = 6.15 / 0.3
v2 = 20.5 m/s
The new velocity of motion is 20.5 m/s.
Please help me this is worth allot
The eagles suck, so do the giants and the jets and jaguars are irrelevant
anyone wanna argue
Naw ur pretty accurate, heck collage is the only football worth watching most the time. Hook'um horns!
Please help I’ll give you brain
Answer:
Explanation:
distance (km)
a) As near as I can tell from the graph, the distance travelled was 4km
b) I would answer 40 minutes, but don't be surprised if your instructor says 30 minutes.
c) The average speed is 4 km/40 minutes = 0.1 km/minute
How much force is needed to accelerate 250 kg at a rate of 6 m/s/s?
Answer:
[tex]1500 \: \mathrm{N}[/tex]
Explanation:
The equation [tex]F=ma[/tex] represents the force needed.
Plugging in [tex]m=250[/tex] and [tex]a=6\: \mathrm{m/s^2}[/tex], we find that the force needed to accelerate a 250 kg object at a rate of [tex]6 \: \mathrm{m/s^2}[/tex] to be [tex]\fbox{$1500 \: \mathrm{N}$}[/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:
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 wave has frequency of 50 Hz and a wavelength of 10 m. What is the speed of the wave? Group of answer choices
Explanation:
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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:
1. A kangaroo hops 84 m to the east in 7 seconds.
o What is the kangaroo's speed? 12 m/s
o What is the kangaroo's velocity?
Explanation:
Given parameters:
Distance hopped = 84m
Displacement = 84m due east
Time = 7s
Unknown:
Speed of kangaroo = ?
Velocity of kangaroo = ?
Solution:
To solve this problem,
Speed = [tex]\frac{distance}{time }[/tex] = [tex]\frac{84}{7}[/tex] = 12m/s
Velocity = [tex]\frac{displacement}{time}[/tex] = [tex]\frac{84}{7}[/tex] = 12m/s due east
Will mark brainliest Why are acoustic panels are used in concert halls
Answer:
what person above said is correct
Explanation:
The walls of the concert halls are used to control the acoustic. ... Rough surfaces can also be used to disperse sound in all directions – this might be used in concert halls to get rid of echoes that would distract from performances.
An acoustic panel is a sound-absorbing panel used to mitigate noise and reduce the reverberation and echo in a space. For both types, we can talk about different principles of good acoustics: absorption, diffusion, and attenuation. These are all linked to the acoustic performance of the panels.
brainliest?Question 17 of 25
A sound wave from a brass bell passes through the air with a
wavelength of 3.5 m. When the sound wave originated in the
brass bell, its wavelength was 47 m. If the sound wave has a
constant frequency of 100 Hz, what was its speed as it
traveled through the brass bell? (The equation for wave speed
is v= f*1.)
A. 3,500 m/s
B. 4,700 m/s
C. 350 m/s
D. 470 m/s
Answer:
The speed of the wave as it travelled through the brass bell is;
B. 4,700 m/s
Explanation:
The given parameters are;
The wavelength of the sound wave produced from the brass bell, [tex]\lambda _{(air)}[/tex] = 3.5 m
The wavelength of the wave in the brass bell, [tex]\lambda _{(brass \ bell)}[/tex] = 47 m
The frequency of the wave in the brass bell, f = 100 Hz
The given equation for wave speed, v = f × λ
Therefore, the speed of the wave as it travelled through the brass bell, [tex]v _{(brass \ bell)}[/tex], is given as follows;
[tex]v _{(brass \ bell)}[/tex] = f × [tex]\lambda _{(brass \ bell)}[/tex] = 100 Hz × 47 m = 4,700 m/s
The speed of the wave as it travelled through the brass bell = [tex]v _{(brass \ bell)}[/tex] = 4,700 m/s
Answer:
B.) 4700 m/s
Explanation:
On Earth, a spring stretches by 5.0 cm when a mass of 3.0 kg is suspended from one end.
The gravitational field strength on the Moon is
1/6 of that on Earth.
Which mass, on the Moon, would stretch the spring by the same extension?
Reasons too :(
igcse physics
Answer:
Mass = 18.0 kg
Explanation:
From Hooke's law,
F = ke
where: F is the force, k is the spring constant and e is the extension.
But, F = mg
So that,
mg = ke
On the Earth, let the gravitational force be 10 m/[tex]s^{2}[/tex].
3.0 x 10 = k x 5.0
30 = 5k
⇒ k = [tex]\frac{30}{5}[/tex] ................ 1
On the Moon, the gravitational force is [tex]\frac{1}{6}[/tex] of that on the Earth.
m x [tex]\frac{10}{6}[/tex] = k x 5.0
[tex]\frac{10m}{6}[/tex] = 5k
⇒ k = [tex]\frac{10m}{30}[/tex] ............. 2
Equating 1 and 2, we have;
[tex]\frac{30}{5}[/tex] = [tex]\frac{10m}{30}[/tex]
m = [tex]\frac{900}{50}[/tex]
= 18.0
m = 18.0 kg
The mass required to produce the same extension on the Moon is 18 kg.
Answer:
18 kg
Explanation:
weight (N) = mass (kg) × gravitational acceleration (m/s²)force (N) = k (spring constant) × extension (m)On Earth, acceleration of gravity is 10 m/s²
weight = 3.0 (kg) × 10 (m/s²)weight = 30 (N)Since weight is a force, the force is 30 N. The value of spring constant is unknown
30 (N) = k × 5 (m)k = 6 (m/N)Spring constant is 6. Now let's find the mass on the Moon
mass (kg) × gravitational acceleration (m/s²) = k (spring constant) × extension (m)Gravitational acceleration of the moon is 1/6 of that on Earth. Earth's g = 10, so Moon's g = 10/6
m × 10/6 = 6 × 5m = 30/(10/6)m = 18The mass is 18 kg
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:
How many moons are in our solar system?
ANSWER QUICK 30 POINTS
What force controls the movement of the planets around the sun, holds together stars grouped in galaxies, and galaxies grouped in clusters? Thoroughly explain your answer, making sure to include an example and describe how this force keeps planets in orbit. Make sure to write at least 3-5 sentences and proper conventions (spelling, grammar, punctuation, etc.) to respond. Put all answers in your own words
Answer:
Gravity controls the movement of the planets around the sun, holds together stars grouped in galaxies, and galaxies grouped in clusters. The Universal Law of Gravitation depends on two things. First it depends on mass of each object and the second factor is the distance between two objects. If the mass of one object is Larger, the gravitational pull towards it will be larger and the smaller distance, the larger the gravitational pull will be between the objects. Therefore the Larger planets have more moon and the inner planets have less.
Explanation:
Two resistors are used in an experiment. Resistor 1 had a resistance of 4 ohms and resistor 2 has a resistance of 2 ohms. Which resistor will have the bigger current flowing through it if the potential difference is constant
Answer:
2ohms resistor
Explanation:
According to ohms law
V= IR
V is the potential difference
I is the current
R is the resistance
Since they have the same potential difference, this shows that they are connected in parallel
Let assume V = 20V
For the 4ohms resistor
I = V/R
I = 20/4
I = 5A
For the two ohms resistor
I = V/R
I = 20/2
I = 10A
This shows that the 2ohms resistor will have the bigger current because the smaller the load, the bigger the current and vice versa
Answer:
2
Explanation:
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