Answer:
The answer of this question is windmill
To a stationary observer, a man jogs east at 2 m/s and a woman jogs west at
3 m/s. From the woman's frame of reference, what is the man's velocity?
Answer:
5 m/s east
Explanation:
i just took the test and it was correct
Answer:
Just took the test. 5 m/s east.
Explanation:
g A person exploring a deep cave system becomes injured and needs to be rescued. The fastest way to get them is to pull them straight up out of the cave through a small opening just overhead, using a motor-driven cable. The lift is performed in three stages, each of them 10 m in height (total of 30 meters to extract the person). In the first stage, the person is accelerated to a speed of 5 m/s. They are then lifted at constant speed of 5 m/s, then in the last stage they are slowly decelerated to zero speed. If the person weighs 80 kg, how much work is done in each stage
Answer:
1. W = 8848 J
2. W = 7848 J
3. W = 6848 J
Explanation:
The work (W) can be found using the following equation:
[tex] W = E_{k} + E_{p} [/tex]
Where: E(k) is the kinetic energy and E(p) is the potential energy
Now let's find the work for every stage.
Stage 1:
[tex] W = E_{k} + E_{p} = \frac{1}{2}mv^{2} + mgh [/tex]
Where: m is the mass, g is the gravity, h is the height, v is the speed
[tex] W = \frac{1}{2}mv^{2} + mgh = \frac{1}{2}80 kg*(5 m/s)^{2} + 80 kg*9.81 m/s^{2}*10 m = 8848 J [/tex]
Stage 2:
[tex] W = E_{k} + E_{p} = 0 + E_{p} [/tex]
The kinetic energy is equal to zero because the acceleration is constant.
[tex] W = E_{p} = mgh = 80 kg*9.81 m/s^{2}*10 m = 7848 J [/tex]
Stage 3:
[tex] W = E_{k} + E_{p} = \frac{1}{2}mv^{2} + mgh = -\frac{1}{2}80 kg*(5 m/s)^{2} + 80 kg*9.81 m/s^{2}*10 m = 6848 J [/tex]
I hope it helps you!
Physics Vectors-- Please could you help me ? For first question.
A car traveling at 30 m/s is brought to rest at a constant rate in 20 s by applying the brake. a) What is its acceleration? b) How far did it travel after the brake was applied?
FIGURE 1 shows a horizontal human arm lifting a dumbbell. The forearm is
in equilibrium under the action of the weight of the dumbbell, the tension
in the tendon connected to the biceps muscle, and the force exerted on the
forearm itself. (For clarity, the point A where the tendon is attached is drawn
farther from the elbow than its actual position) Given the weight of the forearm
is 20 N and the mass of the dumbbell is 20 kg. The angle between the tension
force and the horizontal, is 80°. The length of the horizontal arm is 0.30 m.
The horizontal distance between elbow pivot and point A is 0.050 m. Find and
the vector and draw free body diagram for this case
Answer:
Explanation:
See attached file for answer.
A car travels at a constant speed around a circular track whose radius is 3.22 km. The car goes once around the track in 248 s. What is the magnitude of the centripetal acceleration of the car
Answer:
a = 1,838.17m/s²
Explanation:
centripetal acceleration a = v²/r
v is velocity of the car
r is the radius = 3.22km = 3220m
time t = 248
First is to find to velocity using the equation of motion:
v = u+gt
v = 0+(9.81)(248)
v = 2,432.88m/s
a = 2,432.88²/3220
a = 5,918,905.0944/3220
a = 1,838.17m/s²
The magnitude of the centripetal acceleration of the car is 1,838.17m/s²
True or false:
A small wire can conduct an infinite amount of current.
Answer:
True
Explanation:
Answer: very true
Explanation:
State and explain Gauss's law in
electrostatics and use it to determine the electric field
intensity due to a line charge.
To find:-
To find the electric field due to a point charge using Gauss's Law .Answer:-
Gauss's law in electrostatics states that the electric flux through a closed surface is equal to 1/ε0 times the charge enclosed by that surface, that is,
[tex]\implies \displaystyle \phi_E = \oint \vec{E} .\vec{ds} \\[/tex]
Also ,
[tex]\implies\displaystyle \oint \vec{E}.\vec{ds} =\dfrac{q}{\epsilon_0} \\[/tex]
Linear density of charge:-
It ise defined as charge per unit length. Mathematically,
[tex]\implies\displaystyle \lambda =\dfrac{q}{\ell} \\[/tex]
where ,
[tex] q[/tex] is the charge .[tex]\ell[/tex] is the length of the conductor.For figure see attachment.
Now let us assume that the linear density of charge is [tex]\lambda[/tex] . There is a point P near the wire at a distance of " r " from it , where we are interested in calculating the electrical field. Imagine a coaxial Gaussian cylinder of length [tex]\ell[/tex] , and radius " r " such that the point P lines on its surface.
Calculating Electrical flux through the cylinder:-
[tex]\implies\displaystyle \phi_E = 0 + 0 + \oint E.ds \\[/tex]
[tex]\implies\displaystyle\phi_E = \oint E.ds \ \cos0^o \\[/tex]
[tex]\implies\displaystyle \phi_E = \oint Eds \\[/tex]
[tex]\implies\displaystyle \phi_E = E\oint ds \\[/tex]
[tex]\implies\displaystyle \phi_E = E (2\pi r\ell) \ \ dots (1) \\[/tex]
From Gauss's law:-
[tex]\implies\displaystyle \phi_E =\dfrac{q}{\epsilon_0} \\[/tex]
[tex]\implies\displaystyle \phi_E = \dfrac{\lambda \ell}{\epsilon_0}\ \dots (2) \\[/tex]
Therefore , from equation (1) and (2) , we have;
[tex]\implies\displaystyle E \times 2\pi r \ell =\dfrac{\lambda\ell}{\epsilon_0}\\[/tex]
[tex]\implies\displaystyle \underline{\underline{\green{ E =\dfrac{1}{4\pi \epsilon_0}\dfrac{2\lambda}{r}}}}\\[/tex]
And we are done!
Leah is sitting on of her surfboard out in the ocean. She is waiting for the perfect wave to come along so she can ride it in to
shore. As she waits, she notices that the waves roll by in patterns, or sets.
As Leah its, she counts the number of waves that pass her during a 10-second period; she counts just 1. She estimates that the
distance between crests is 6 meters. Betty sees the perfect wave and begins paddling. She pushes herself up, stands on the
surfboard and rides the wave all the way in to shore, a distance of about 60 meters. It takes her about 10 seconds to ride the
wave in. Use two methods to calculate the speed of the wave based on the information presented. Are they the same? Explain
how you got your answers.
Answer:
No
Explanation:
S=d/t Speed equals distance divided by time. That's a helpful equation in this case. Leah's wave took 10 seconds, and the distance was 6 meters.
6/10=.6
Betty's wave took 10 seconds, but the distance was 60 meters this time.
60/10=6
We know that 6 and .6 are not the same numbers, so we can see that the waves aren't the same.
<3
APEX PLEASE HELP
To increase the electricity supply in the country, a government needs to build
a new power plant. Which of the following is a cost associated with the use
of nuclear power that should be factored into its decision?
A. Nuclear power produces radioactive waste.
B. Nuclear power does not depend on wind.
C. Nuclear power does not contribute to climate change.
D. Nuclear power can be produced both day and night.
Answer: A. Nuclear power produces radioactive waste.
A metric unit of volume equal to a milliliter
An electron is accelerated from rest by a potential difference of 435 V. It then enters a uniform magnetic field of magnitude 167 mT with its velocity perpendicular to the field. Calculate (a) the speed of the electron and (b) the radius of its path in the magnetic field.
Answer:
(a) the speed of the electron is 1.237 x 10⁷ m/s
(b) the radius of its path in the magnetic field is 4.21 x 10⁻⁴ m
Explanation:
Given;
potential difference, V = 435 V
magnetic field, B = 167 mT = 0.167 T
(a) the speed of the electron
eV = ¹/₂mv²
[tex]v = \sqrt{\frac{2eV}{m} }\\\\ v = \sqrt{\frac{2(1.6*10^{-19})(435)}{(9.1*10^{-31})}}\\\\v = 1.237*10^7 \ m/s[/tex]
(b) the radius of its path in the magnetic field
[tex]r = \frac{mv}{eB}\\\\r = \frac{(9.1*10^{-31})(1.237*10^7)}{(1.6*10^{-19})(0.167)}\\\\r = 4.21 *10^{-4} \ m[/tex]
I WILL MARK YOU AS BRAINLIEST IF RIGHT
In order to climb up a mountainside, a train needs to start at a speed of 40 mph. The speed limit on the track, however, is 25 mph. How much time does the train need to get up to 40 mph if it can accelerate 4 mph per minute ?
Explain whether the size of an object's displacement could be greater than the distance the object travels
Answer:
Displacement is always less than or equal to distance. Note that distance is a scalar whereas displacement is a vector. So displacement cannot be more than distance.
The size of an object's displacement can never be greater than the distance the object travels by the object because displacement is the shortest distance traveled between the initial and the final position.
What is displacement?An object's position changes if it moves in relation to a reference frame, such as when a passenger moves to the back of an airplane or a professor moves to the right in relation to a whiteboard.
Displacement can never be greater than the distance covered by any moving body.
Since displacement is the smallest distance between the beginning and final positions, the size of an object's displacement can never be more than the distance the object travels.
Learn more about displacement here, refer to the link;
brainly.com/question/10919017
#SPJ2
If you had a 30 pound barbell at home and you wanted to compare your muscular endurance to your younger brother's which method would be the best to use.
Answer:A
Explanation:
Absolute method
Answer:
absolute method
Explanation:
trust
what happends when you slowly pull out the paper while theirs a coin on top
Where is the magnetic south pole compared to the geographical north pole?
Currently, the magnetic south pole lies about ten degrees distant from the geographic north pole, and sits in the Arctic Ocean north of Alaska. The north end on a compass therefore currently points roughly towards Alaska and not exactly towards geographic north.
Which direction is the force of gravity on earth
Answer:
It is toward the center
Explanation:
Someone is spinning a basketball on his finger. If it is spinning at a rate of 8.92 times per second, what is the basketball's angular velocity in units of radians per second?
Answer:
angular velocity = 56.04 rad/s.
Explanation:
It is given that,
The baseball is spinning at the rate of 8.92 times per second.
We need to find the basketball's angular velocity in units of radians per second.
Here, frequency of the baseball is 8.92 Hz.
We know that Angular velocity is given by :
[tex]\omega=2\pi f\\\\\omega=2\pi \times 8.92 \\\\\omega=56.04\ rad/s[/tex]
So, the angular velocity of the basketball is 56.04 rad/s.
this is a Physical Education question
Position vs Time
for Two Cars
Which statements describe the motion of car A and car
B? Check all that apply.
Car A and car B are both moving toward the origin.
Car A and car B are moving in opposite directions.
Car A is moving faster than car B.
A
B
O Car A and car B started at the same location.
Position (m)
O Car A started ahead of car B.
Time (s)
) Intro
Done
Explanation:
Based on the diagram below we can make the following conclusions that:
Car A and Car B are moving in opposite directionsCar A is moving faster than Car B.This conclusion is based on the type of slope evident in each case. One has a positive slope, the other a negative slope.
Why does a sound come out when you blow into a bottle?
When does the jet of air convert to vibrations?
What element has similar chemical properties to lodine?*
Answer:
Iodine is most similar to the other non- metals in the Halogen Family, such as Fluorine, Chlorine, Bromine, Astatine .
Explanation:
give reasons with examples why houses are made up of bricks and cement instead of metal
Answer:
The most important is that the thermal conductivity of the armadillas several orders of magnitude lower than the thermal conductivity of the metal, therefore it is easier to maintain the temperature in winter
Explanation:
Cement and bricks are used in the construction of houses instead of metal, for several reasons
* The most important is that the thermal conductivity of the armadillas several orders of magnitude lower than the thermal conductivity of the metal, therefore it is easier to maintain the temperature in winter
* Metal has more oxidation problems than brick
* The cost of sheet metal is higher than the cost of cement brick.
A small mailbag is released from a helicopter that is rising\ steadily at 2.32 m/s.
(a) After 5.00 s, what is the speed of the mailbag?
(b) How far is it below the helicopter?
(c) What are your answers to parts (a) and (b) if the helicopter is rising steadily at 2.32 m/s?
Given parameters:
Velocity of the helicopter = 2.32m/s
Time given = 5.00s
Unknown:
a. Speed of the mailbag after 5s
b. How far is the mail bag below the helicopter
Solution:
In this problem, we must apply the appropriate motion equation to solve.
For a;
v = u + gt
v is the velocity of the mail bag
u is the initial velocity
g is the acceleration due to gravity
t is the time taken
Notice that the initial velocity of the mail bag is 0;
V = 0 + 9.8 x 5 = 49m/s
For b;
Using;
h = ut + [tex]\frac{1}{2}[/tex] gt²
where u is 0;
h = [tex]\frac{1}{2}[/tex] x 9.8 x 5² = 122.5m
Lien is pushing a box across a table. She used a force of 100 N to get the box moving. Which force did she overcome
to get the box moving?
O the downward force of gravity on the box
O the upward force of the table on the box
the reaction force on the box
O the push force on the box
Answer:
the reaction force on the box
Explanation:
In order to push or pull an object, an external force is needed to overcome the weight of that object. This force is called ACTION FORCE. However, according to 3rd law of Newton, which states that for every action, there is an equal and opposite reaction, an opposite force counters the object in an opposite direction. This force is called REACTION FORCE.
According to this question, Lien is pushing a box across a table. She used a force of 100 N to get the box moving. This means that she had to overcome an opposite force called REACTION FORCE, with an ACTION FORCE of 100N
Answer:
C. the reaction force on the box
Explanation:
i literally just finished the quiz
Wanda is afraid of gaining weight and putting herself at high risk for disease. she works out on a regular basis and eats right most of time. recently, Wanda some testing done. her BMI with some 17.2 and her waist circumference is 30 inches. what statement best describes next move for Wanda so she will be at the least risk for disease?
Answer:
C. Wanda's waist circumference indicates that she is not at risk, but her BMI indicates that she underweight. She should develop a plan to move her BMI into the normal range.
Explanation:
edge 2020 Brainliest would be appreciated
Answer:
Wanda's waist circumference indicates that she is not at risk, but her BMI indicates that she underweight. She should develop a plan to move her BMI into the normal range.
Explanation:
I just did the Cumulative Exam Review
PLEASE HELP! WILL MARK BRAINLIEST!
In this graphical representation of a vector, which direction is designated as positive?
a) horizontal
b) vertical
c) downward
d) upward
Answer:
D
Explanation:
when you try to find out if it is positive, the line goes from left to right, and in this question the line is going upward.
A target lies flat on the ground 4 m from the side of a building that is 10 m tall, as shown below.
The acceleration of gravity is 10 m/s^2.
Air resistance is negligible.
A student rolls a 4 kg ball off the horizontal
the roof of the building in the direction of the
target.
The horizontal speed v with which the ball
must leave the roof if it is to strike the target
is most nearly
1. v =√3 /4 m/s.
2. v =4√3 /3 m/s.
3. v = 4 m/s.
4. v = 2√2 m/s.
5. v =√2 / 4 m/s.
6. v =√5 / 4 m/s.
7. v = 4√3 m/s.
8. v = 4√5 m/s.
9. v = 6 m/s.
10. v = 4√2 m/s.
Answer:
v = 2√2 m/s
Explanation:
The following data were obtained from the question:
Height (h) = 10 m
Acceleration due to gravity (g) = 10 m/s²
Horizontal distance (s) = 4 m
Horizontal velocity (v) =.?
Next, we shall determine the time taken for the ball to get to the target.
This can be obtained as shown below:
Height (h) = 10 m
Acceleration due to gravity (g) = 10 m/s²
Time (t) =?
h = ½gt²
10 = ½ × 10 × t²
10 = 5 × t²
Divide both side by 5
t² = 10/5
t² = 2
Take the square root of both side.
t = √2 s
Finally, we shall determine the horizontal velocity as shown below:
Horizontal distance (s) = 4 m
Time (t) = √2 s
Horizontal velocity (v) =.?
s = vt
4 = v × √2
Divide both side by √2
v = 4 /√2
Rationalise the denominator
v = (4 /√2) × √2/√2
v = 4 × √2 / √2 × √2
v = 4 × √2 / 2
v = 2√2 m/s
What are tides?
O Circulation of water
O Glaciers melting causing rising water
O Wind pushing ocean water
O Rise and fall of the water level on the shore
Answer:
4th
Explanation:
Rise and fall of the water level on the sea shore