Answer:
D
Explanation:
A freight train has a mass of 3.8 x 10^7 kg. The locomotive can exert a force of 6.5 x 10^5 N to pull the train.
Required:
a. How long does it take the train to go from rest to 50 km/hr?
b. If there is air resistance of 2.0 x 10^5 N, what is the acceleration of the train, and how long does it take the train to go from rest to 50 km/hr?
Answer:
(a) The time taken for the plane to reach 50 km/hr is 811.97 s
(b) (i) the acceleration of the plane is 0.012 m/s²
(ii) The time taken for the plane to reach 50 km/hr is 1172.85 s
Explanation:
Given;
mass of the freight train, m = 3.8 x 10⁷ kg
force applied to pull the train, F = 6.5 x 10⁵ N
a. How long does it take the train to go from rest to 50 km/hr?
Given;
initial velocity, u = 0
final velocity, v = 50 km/hr = 13.889 m/s
Apply Newton's second law of motion to determine the time traveled by the train at the given speed;
[tex]F = ma = \frac{m(v-u)}{t}\\\\t = \frac{m(v-u)}{F}\\\\t = \frac{3.8*10^7(13.889-0)}{6.5*10^5}\\\\t = 811.97 \ s[/tex]
(b)
(i) the acceleration of the plane
Given;
air resistance, = 2.0 x 10⁵ N
Apply Newton's second law of motion;
∑F = ma
6.5 x 10⁵ N - 2.0 x 10⁵ N = ma
4.5 x 10⁵ N = ma
[tex]a = \frac{4.5 * 10^5 }{m}\\\\a = \frac{4.5 * 10^5 }{3.8*10^7}\\\\a = 0.012 \ m/s^2[/tex]
(ii) time taken for the plane to reach 50 km/hr is given by;
[tex]F = \frac{m(v-u)}{t}\\\\t = \frac{m(v-u)}{F}\\\\t = \frac{3.8*10^7(13.889-0)}{4.5*10^5}\\\\t = 1172.85 \ s[/tex]
A pasta factory made 3.84 pounds of pasta in 4 minutes. How much pasta did the factory make in each minute? plzz help me
[tex]{\underline{\green{\textsf{\textbf{ Answer : }}}}}[/tex]
➡ 0.96 pounds in a minute.
A force F = (2xî + 4yĵ), where F is in newtons and x and y are in meters, acts on an object as the object moves in the x-direction from the origin to x = 4.99 m. Find the work W = ∫ F · dr done by the force on the object (in J).
Answer:
Work done, W = 24.9001 J
Explanation:
Given that,
Force, F = (2xî + 4yĵ) Where x and y are in meters
This force acts on an object as the object moves in the x-direction from the origin to x = 4.99 m.
We need to find the work done by the force on the object. It is given by :
[tex]W=\int\limits^a_b {F dr} \\\\W=\int\limits^{4.99}_0 {(2xi+4yj)dx} \\\\W=\int\limits^{4.99}_0 {2xi\ dx} \\\\W=x^2|_0^{4.99}\\\\\text{Applying limits}\\\\W=(4.99)^2-0^2\\\\W=24.9001\ J[/tex]
So, the work done is 24.9001 J.
An amateur golfer swings a golf club, striking a golf ball that has a mass of 55.0 g. The club is in contact with the ball for only 0.00360 s. After the collision, the ball leaves the club at a speed of 34.0 m/s. What is the magnitude of the average force (in N) exerted on the ball by the club?
Answer:
The average force ≅ 519.44 N.
Explanation:
Impulse = change in momentum of a body
i.e Ft = m(v - u)
where F is the force, t is the time, m is the mass of the body, v is the final velocity and u is the initial velocity.
m = 55.0 g (0.055 Kg), t = 0.00360 s, v = 34.0 m/s, since the ball was initially at rest; u = 0 m/s
So that,
F x 0.00360 = 0.055(34 - 0)
F x 0.00360 = 0.055 x 34
= 1.87
F = [tex]\frac{1.87}{0.0036}[/tex]
= 519.4444
The average force exerted on the ball by the club is approximately 519.44 N.
Review Question 1
A group of students collected the data shown below while attempting to
measure the coefficient of static friction (of course, it looks like this group
varied the amount of mass sitting on the block with each trial - this is not
recommended). Nonetheless, what is their average coefficient of static friction?
Mass of block (g)
Hanging mass (kg)
Trial
1
105
0.053
2
165
0.081
3
220
0.118
4
280
149
5
315
0.180
6
385
0.198
Answer:
The average coefficient of static friction = 0.130
Explanation:
The average coefficient of static friction = [tex]\frac{sum of coefficient of static friction}{number of trials}[/tex]
From the given question, the coefficient of static friction given are:
0.053, 0.081, 0.118, 0.149, 0.180, 0.198
Thus,
the sum of the given coefficient of static friction = 0.053 + 0.081 + 0.118 + 0.149 + 0.180 + 0.198
= 0.779
The average coefficient of static friction = [tex]\frac{0.779}{6}[/tex]
= 0.129833
= 0.130
Therefore, the average coefficient of static friction is 0.130.
The gravitational field at the Moon in N/kg due to the Earth is approximately (G = 6.67 × 10-11 N m2/kg2, the mass of the Earth is 5.98 × 1024 kg, and the distance to the Moon is 3.85 × 108 m)
Answer:
F = 2.69 10⁻³ m [ N]
Explanation:
This exercise asks to calculate the gravitational field of the Earth on the lunar surface, let's use the universal gravitation law
F = G m M / r²
where m is the mass of the body, M the mass of the Earth and r the distance between the Earth and the Moon
F = (G M / r²) m
F = (6.67 10⁻¹¹ 5.98 10²⁴ / (3.85 10⁸)² ) m
F = 2.69 10⁻³ m [ N]
This force is directed from the Moon towards the Earth, therefore it reduces the weight of the body
What does a switch in an electrical circuit do?
O A. It concentrates negative charges on one side of the circuit when it
is open.
B. It concentrates negative charges on one side of the circuit when it
is closed.
C. It allows electrons to flow from one part of the circuit to another
when it is open.
D. It allows electrons to flow from one part of the circuit to another
when it is closed.
Answer:
It allows electrons to flow from one part of the circuit to another
when it is closed.
Explanation:
hope this helps <3 !!
Answer: D
Explanation:
4.
Vectors P and Q are drawn to scale.
P
Which diagram represents the vector (P +Q)?
A
B
с
D
plz help I will fail.
can anyone plz help me.
plz
Answer:
hindi ko gets
Explanation:
ang gulo naman nyan
This is my question
Answer:
N = 470 [N]
Explanation:
The normal force is defined as the reaction exerted by the surface where the body is located in the opposite direction to the weight component.
It can be easily calculated by means of the product of mass by gravitational acceleration.
N = m*g
where:
N = normal force [N] (units of Joules)
m = mass = 47 [kg]
g = gravity acceleration = 10 [N]
N = 47*10
N = 470 [N]
Detlev walks 1000 meters north to the store and walks back 900 meters south to his friends house. The friends house is 100 meters to the north of Detlev’s house. What was Detlev’s Travel Distance?
A train slows down as it rounds a sharp horizontal turn, going from 88.0 km/h to 52.0 km/h in the 18.0 s that it takes to round the bend. The radius of the curve is 120 m. Compute the acceleration at the moment the train speed reaches 52.0 km/h. Assume the train continues to slow down at this time at the same rate.
Answer:
The acceleration at the moment the train speed reaches 52 kilometers per hour is approximately 1.826 meters per square second.
Explanation:
According to Rotational Physics, the total acceleration of the train rounding the horizontal turn is a combination of tangential ([tex]a_{t}[/tex]) and radial accelerations ([tex]a_{r}[/tex]), measured in meters per square second. The former one represents the change in the magnitude of the velocity, whereas the latter one represents the change in its direction. By definition of magnitude and Pythagorean Theorem we get that magnitude of total acceleration ([tex]a[/tex]), measured in meters per square second, is:
[tex]a = \sqrt{a_{r}^{2}+a_{t}^{2}}[/tex] (Eq. 1)
Magnitudes of tangential and radial accelerations are determined by using the following formulas:
[tex]a_{t} = \frac{v_{f}-v_{o}}{t}[/tex] (Eq. 1)
[tex]a_{r} = \frac{v_{f}^{2}}{R}[/tex] (Eq. 2)
Where:
[tex]v_{o}[/tex], [tex]v_{f}[/tex] - Initial and final speeds, measured in meters per second.
[tex]t[/tex] - Time, measured in seconds.
[tex]R[/tex] - Radius, measured in meters.
If we know that [tex]v_{o} = 24.444\,\frac{m}{s}[/tex], [tex]v_{f} = 14.444\,\frac{m}{s}[/tex], [tex]t = 18\,s[/tex] and [tex]R = 120\,m[/tex], then the magnitude of the total acceleration when the train speed reaches 52 kilometers per hour is:
[tex]a_{t} = \frac{14.444\,\frac{m}{s}-24.444\,\frac{m}{s} }{18\,s}[/tex]
[tex]a_{t} = -0.556\,\frac{m}{s^{2}}[/tex]
[tex]a_{r} = \frac{\left(14.444\,\frac{m}{s} \right)^{2}}{120\,m}[/tex]
[tex]a_{r} = 1.739\,\frac{m}{s^{2}}[/tex]
[tex]a = \sqrt{\left(-0.556\,\frac{m}{s^{2}} \right)^{2}+\left(1.739\,\frac{m}{s^{2}} \right)^{2}}[/tex]
[tex]a \approx 1.826\,\frac{m}{s^{2}}[/tex]
The acceleration at the moment the train speed reaches 52 kilometers per hour is approximately 1.826 meters per square second.
A 12 volt car battery pushes charge through the headlight resistance of 10 ohms. How much current is passing through the circuit
Answer:50
Explanation:
The current flowing through the given circuit is 0.12 A.
The given parameters;
voltage of the battery, V = 12Vresistance of the headlight, R = 10 OhmsThe current passing through the headlight is calculated by applying Ohms law as shown below;
V = IR
where;
I is the current flowing the circuitR is the resistance to the flow of current in the circuitSubstitute the given parameters and solve the current flowing in the circuit;
[tex]V = IR\\\\I = \frac{V}{R} \\\\I = \frac{12}{10} \\\\I = 0.12 \ A[/tex]
Thus, the current flowing through the given circuit is 0.12 A.
Learn more here:https://brainly.com/question/18515095
Draw a graph of these results
Answer:
Actually I know but I can't cause it will take time
if 6.24×10¹⁸ electron pass through a wire in 1s how many pass through it during a time interval of 2hr, 47min and 10s
During a time interval of 2hr, 47min and 10s, 6.25× [tex]10^{28[/tex] electrons pas through the wire.
What is electron?A negatively charged subatomic particle known as an electron can either be free or attached to an atom (not bound). One of the three main types of particles within an atom is an electron that is bonded to it; the other two are protons and neutrons.
Given parameter:
The electron pass through a wire in 1s = 6.24 × [tex]10^{18}[/tex].
The time interval = 2 hour 47 minute 10 second.
= (2×60×60 + 47×60 +10) second = 1030 second.
Total number of electrons pass through the wire during the time interval = number of electrons pass per second × time interval in second.
= 6.24×[tex]10^{24[/tex]×1030
= 6.25× [tex]10^{28[/tex].
Hence, total number of electrons pass during a time interval of 2hr, 47min and 10s is 6.25× [tex]10^{28[/tex].
Learn more about electron here:
https://brainly.com/question/1255220
#SPJ2
how can we show the magnetic force of a magnet illustrate with an example
Answer:
take some sharp mixture of iron spread it from up the magnet you will see the magnetic field of magnet
I'll give brainliest if you give me a good awnser. :)
A football player kicks a ball with a force of 50 N. Find the impulse on the ball if his foot stays in contact with the football for 0.01 second.
Answer:
0.5
Explanation:
A balloon is inflated outside on a cool morning. As the temperature rises, reaching its peak in the afternoon, the volume of the balloon will Choose... . As the temperature cools down again in the evening, the volume of the balloon will
Answer:
The volume of the balloon will increase when temperature rises, and the volume of the balloon decreases to its initial value as temperature cools down.
Explanation:
An inflated balloon contains a definite amount of gas. Since the temperature varies, its volume would vary with respect to temperature.
The increasing temperature causes an increase in the average kinetic energy of the molecules of the gas inside the balloon. Therefore, the volume of the balloon increases as the temperature rises.
As the temperature cools down, assuming that the balloon didn't burst in the process, the kinetic energy of the molecules of the gas decreases. So that the volume of the balloon decreases to its initial value.
А)
An automobile traveling along a straight road
increases its speed from 48 ft/s to 66 ft/s in
180 ft.
If the acceleration is constant, how much
time elapses while the auto moves the 180 ft?
Answer in units of s.
Answer:
4.5s
Explanation:
u=30m/s
v=50m/s
s=180m
a=constant(given)
By third equation of motion, v
2
=u
2
+2as
(50)
2
=(30)
2
+2a(180)
a=
3
40
m/s
2
By first equation of motion, v=u+at
50=30+(
9
40
)t
t=
2
9
=4.5sec
"She finished the sprint with the speed of a cheetah." This statement represents which of the
following functions of language? (2 points)
correct answer is poetic.
Answer:
Poetic
Explanation:
I took the test
Answer:
Poetic
Explanation:
I got it right on the test
Give real-world examples of evidence that supports the evolution of Earth in each category:
Deposition -
Chemical weathering -
Volcanic eruption -
Answer:
real world examples
Explanation:
concave wave rock- The wave rock is formed by weathering of the surrounding area, which helps in proving the deposition part, as the wave rock was below the ground, occurred due to deposition of rock years over years. It is made from very tough material from its surrounding. The weathering reduced the surrounding terrain, while the bedrock remained to witness for the history. --Also, volcanic eruptions have changed earth greatly. EX- Ash and sulfur went into Earth's atmosphere because of the Tambora eruption which dimmed incoming sunlight. It lowered global temperatures by about 3°F. The Mount Pinatubo of 1991 that erupted in the Philippines cooled the planet by about 1°F.
Some vitamins can not be stored in the body and so they must be replenished by intake on a regular basis. Which of the following is not true about these vitamins?
1 they are water-soluble
2 they need to be taken daily
3 they are fat-soluble
4 They include vitamin C and the B complex vitamins.
Answer:
Explanation:
3
Once a player catches the Frisbee they are only allowed to pivot like in
basketball.
True
False
i need this ASAP please!!!
What is the significance of the discovery of exoplanets?
a. they may possibly be inhabited or harbor life.
b. they can provide natural resources for the future.
c. they help our understanding of the formation of planetary bodies.
d. they help calibrate gps satellites.
e. they help understand the nature of the expansion of the universe.
Answer:
C. the help our understanding of the formation of planetary bodies.
Explanation:
this is the answer of PLATO
what is the state of y when y = k/x, x is halved.
Answer:
y becomes doubled.
Explanation:
If;
y = [tex]\frac{k}{x}[/tex]
what is the state of y when x is halved;
the given expression is an inverse relationship. When y increases, x is supposed to decrease and vice versa.
if x is halved; x = [tex]\frac{x}{2}[/tex]
[tex]\frac{k}{\frac{x}{2} }[/tex] = [tex]\frac{2k}{x}[/tex]
Now compare :
[tex]\frac{k}{x}[/tex] : [tex]\frac{2k}{x}[/tex]
we see that y becomes doubled
Help me with this please !!
Pt 1_It would be harder to do experiments on or near jupiter for many reasons ! One being that jupiters top layers are known to be gas. However if we could hover over Jupiter and test its gravity, describe or sketch the shape of the position vs time graph for a dropped object.
PT2_ The acceleration due to gravity near Jupiter is 25.95m/s. If a hammer were dropped, how fast wouldit be going after falling 20.0 meters. Show your work !
Answer:
he is right he Is
Explanation:
step by step explanation
answer pls urgent pls
Answer:
[tex]\huge\boxed{\sf Hen's \ Egg}[/tex]
Explanation:
Seen with an unaided eye means that is visible to the naked eye.
So,
Hen's Egg can be seen with an unaided eye.
However, Red Blood Cells (RBCs) and Sperm cells need a microscope for them to be seen!
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AnonymousHelper1807If you measured the final velocity of the car to be 1 m/s and the initial mass of the car remains the same, how much coal was added to the car in kg
Complete Question
The complete question is shown on the first uploaded image
Answer:
a
[tex]p = 14033.7 \ kg\cdot m/s[/tex]
b
[tex]v = 1.22 \ m/s[/tex]
c
[tex]m_2 = 9506.7 \ kg[/tex]
Explanation:
From the question we are told that
The mass of the coal car is [tex]m_1 = 4527 \ kg[/tex]
The velocity is [tex]v_i = 3.1 \ m/s[/tex]
The load of coal dropped is [tex]m_2 = 6952 \ kg[/tex]
Generally the momentum of the system before the coal is added is mathematically represented as
[tex]p = m_j * v_i[/tex]
=> [tex]p = 4527 * 3.1[/tex]
=> [tex]p = 14033.7 \ kg\cdot m/s[/tex]
Generally from the law of momentum conservation is mathematically represented as
[tex]m_1 * v_i + m_2 * v_2 = (m_1 + m_2 )v[/tex]
Here [tex]v_2[/tex] is the velocity of the load before it is dropped and the value is 0 m/s
So
=> [tex]v =\frac{m_1 * v_i }{m_1 + m_2}[/tex]
[tex]v = \frac{4527 * 3.1 }{( 4527 + 6952 )}[/tex]
=> [tex]v = 1.22 \ m/s[/tex]
When v = 1m/s and [tex]m_1[/tex] remain the same
Then
=> [tex]1 =\frac{4527 * 3.1 }{4527 + m_2}[/tex]
=> [tex]4527 + m_2 = 14033.7[/tex]
=> [tex]m_2 = 9506.7 \ kg[/tex]
free brainlyest. if get thes quston right Devlin recorded the number of days of rain for his town over three months. The bar graph below shows his data.
Bar Graph 1
Explain why his data is more about climate than weather.
Question 12 options:
Answer:
Weather is the conditions (temperature, wind etc.) at a given time, like on that day. Climate, which is what his data would show, is the conditions over an extended period of time like the 3 months he collected data
2 examples of where ground water comes from
Answer: Example of ground water
Explanation: Groundwater is part of the hydrologic cycle, originating when part of the precipitation that falls on the Earth's surface sinks (infiltrates) through the soil and percolates (seeps) downward to become groundwater.
The power rating of a 400-ΩΩ resistor is 0.800 W.
Required:
a. What is the maximum voltage that can be applied across this resistor without damaging it?
b. What is the maximum current it can draw?
Answer:
voltage= 17.88volts
current= 0.04 amps
Explanation:
Step one:
given data
resistance R=400 ohms
Power P= 0.8W
a. What is the maximum voltage that can be applied across this resistor without damaging it?
the expression relating power and voltage is
P=V^2/R
substituting we have
0.8=V^2/400
V^2=0.8*400
V^2=320
V=√320
V=17.88 volts
the maximum voltage is 17.88volts
b.What is the maximum current it can draw?
we know that from Ohm' law
V=IR
17.88=I*400
I=17.88/400
I=0.04amps