A roller coaster has a vertical loop with radius 29.5 m.What is the minimum speed of the roller coaster car can have at the top of the loop if the passengers do not lose contact with the seats?
A) 10.0 m/s
B) 14.0 m/s
C) 17.0 m/s
D) 19.0 m/s
Answer:the Minimum speed , v of the roller coster = 17.0 m/s --c
Explanation:
According to Newton's First law of Motion which state that all object will remain at rest unless an external force is applied on the body to act otherwise.
Therefore the Force exerted/ acting on the surface of the roller coaster will be equal to 0,
Net Force = 0
Remember that , Force = mg = Mv ²/r = 0
Net Force =mv ² / r - mg = 0
mv²/ r - mg = 0
(diving through by m)
v²/r -g = 0
v² = gr
v= [tex]\sqrt{gr}[/tex]
where g, acceleration due to gravity= 9.8m/s2 and radius, r = 29.5m
v= [tex]\sqrt{9.8m/s2 X 29.5m }[/tex]
v =[tex]\sqrt{ 289}[/tex]
v= 17.0 m/s
Therefore, the Minimum speed , v of the roller coaster = 17.0 m/s
Cindy has been working for 8 years and she’s built up a huge emergency fund
Answer:The answer will be B :) hope this helps!
Explanation:
what
material gives the soil its high fertility?
Answer:
Humus
Explanation:
Its Humus I believe. I remember learning something like this.
What is one question you would ask a professional athlete?
Answer:
Why do you do sports, when you could be a doctor and helping the sick children, or saving the worlds ocean?
Explanation:
A stone is dropped vertically downwards. What is the velocity of the rock after 4 seconds ? What is the displacement of the rock after 4 seconds ?
Answer:
Vf = 39.2 m/s
h = 78.4 m
Explanation:
Using first equation of motion for vertical motion:
Vf = Vi + gt
where,
Vf = Final Velocity = ?
Vi = Initial Velocity = 0 m/s
g = 9.8 m/s²
t = time taken = 4 s
Therefore,
Vf = 0 m/s + (9.8 m/s²)(4 s)
Vf = 39.2 m/s
Now, we use second equation of motion
h = Vi t + (1/2)gt²
where,
h = height covered = ?
Therefore,
h = (0 m/s)(4 s) + (1/2)(9.8 m/s²)(4 s)²
h = 78.4 m
A sled with a mass of 25.0 kg rests on a horizontal sheet of essentially frictionless ice. It is attached by a 5.00-m rope to a post set in the ice. once given a push, the sled revolves uniformly in a circle around the post. If the sled makes five complete revolutions every minute, find the F exerted on it by the rope.
Answer:
The value is [tex]F = 34.3 \ N[/tex]
Explanation:
From the question we are told that
The mass of the shed is [tex]m = 25 \ kg[/tex]
The length of the rope is [tex]l = 5.0 \ m[/tex]
The angular speed of the shed is [tex]w = 5 rev/minute = \frac{2* \pi * 5}{60 }= 0.524 \ rad/sec[/tex]
Generally the force exerted on the shed is mathematically represented as
[tex]F = m * w^2 * l[/tex]
=> [tex]F = 25 * 0.524^2 * 5[/tex]
=> [tex]F = 34.3 \ N[/tex]
The magnitude of the centripetal force on the sled by the rope is 34.3 N.
The given parameters:
mass of the sled, m = 25 kglength of the rope, r = 5 mnumber of revolution per minute, N = 5The angular speed of the sled is calculated as follows;
[tex]\omega = 5 \ \frac{rev}{\min} \times \frac{2\pi \ rad}{1 \ rev} \times \frac{1 \min}{60 \ s} \\\\\omega = 0.524 \ rad/s[/tex]
The magnitude of the centripetal force on the sled by the rope is calculated as follows;
[tex]F = ma_c\\\\F = m\omega ^2 r\\\\F = 25 \times (0.524)^2 \times 5\\\\F = 34.3 \ N[/tex]
Learn more here:https://brainly.com/question/20905151
1. In a particular experiment to study the photoelectric effect, the frequency of the incident light and the temperature of the metal are held constant. Assuming that the light incident on the metal surface causes electrons to be ejected from the metal, what happens if the intensity of the incident light is increased?A. The work function of the metal decreases. B. The number of electrons emitted from the metal per second increases. C. The maximum speed of the emitted electrons increases. D. The stopping potential increases.2. In another experiment, the intensity of the incident light and the temperature of the metal are held constant. Assuming that the initial light incident on the metal surface causes electrons to be ejected from the metal, what happens if the frequency of the incident light is increased? A. The work function of the metal increases. B. The number of electrons emitted from the metal per second increases. C. The maximum speed of the emitted electrons increases. D. The stopping potential increases.
Answer: 1. B. The number of electrons emitted from the metal per second increases.
2. The maximum speed of the emitted electrons increases.
The stopping potential increases
Explanation:
Photoelectric effect is simply referred to as the emission of electrons that occurs when there's an electromagnetic radiation. An example of such electromagnetic radiation is when material is being hit by light.
Assuming that the light incident on the metal surface causes electrons to be ejected from the metal, the number of electrons emitted from the metal per second increases if the intensity of the incident light is increased.
Also, if the initial light incident on the metal surface causes electrons to be ejected from the metal, the maximum speed of the emitted electrons increases and the stopping potential increases.
Calculate the gravitational potential energy of a 8.6-kg mass on the surface of the Earth. Express your answer using two significant figures.
Answer:
The gravitational potential energy of the 8.6 kg mass is 5.38x10⁸ J.
Explanation:
We can find the gravitational potential energy of the mass using the following equation:
[tex] E_{p} = m*g*h [/tex]
Where:
m: is the mass = 8.6 kg
g: is the gravity = 9.81 m/s^{2}
h: is the height = Earth's radius = 6371 km
Hence, we have:
[tex]E_{p} = 8.6 kg*9.81 m/s*6371000 m = 5.38 \cdot 10^{8} J[/tex]
Therefore, the gravitational potential energy of the 8.6 kg mass is 5.38x10⁸ J.
I hope it helps you!
A penny falls 380 meters. If dropped from rest, ignoring any air resistance, what is the velocity at which the penny hits the ground? Show your work.
Answer:
Vf = 86.34 [m/s]
Explanation:
To solve this problem we must use the following equation of kinematics.
[tex]v_{f} ^{2} =v_{o} ^{2} +2*g*y[/tex]
where:
Vf = final velocity [m/s]
Vo = initial velocity = 0 (falls from the rest)
g = gravity acceleration = 9.81 [m/s²]
y = distance = 380 [m]
Vf² = 0 + (2*9.81*380)
Vf = 86.34 [m/s]
Note: The pisitive sign in the equation above means that the movement goes in the same direction of the gravity acceleration, therefore the velocity is increasing when the penny falls.
Q.16 :-If the amplitude of a vibrating membrane is increased by 50%, then the loudness of sound will
increase by
50%
100%
125%
150%
Answer:
B. 100%
Explanation:
When the amplitude of a vibrating membrane increases the loudness of sound increases. Higher amplitude waves will mean more energy and greater intensity which causes the sound to be louder.
Loudness is proportional to the square of the amplitude. This will simply mean when the amplitude of a wave is doubled, the sound will be 4 times louder.
In this case, 50% increase in the amplitude of a vibrating membrane will cause a 100% increase in the loudness of sound.
what is ice wedging?(pls answer now)
Answer:
When the cold weather fills hard surfaces with water, it causes it to freeze and expand, causing cracks in the surface.
A projectile is fired horizontally off the top of a cliff with an initial velocity of 30 m/s. It hits the ground 2.0 seconds later. What is the height of the cliff?
Answer:no
Explanation:
A graph showing the kinetic energy and speed of a moving object is provided.
KE (Joules)
Speed (m/s)
Which of the following can be concluded from the graph?
Kinetic energy only changes when speed changes.
Speed is only related to the size of an object.
Kinetic energy increases as speed increases.
All moving objects have the same kinetic energy.
its the 3rd one kinetic energy increases as speed increases
Accurate radiometric dating typically requires that a rock contains a measurable amount of __________.
Answer:
Both daughter and parent atoms
Explanation:
Daughter atoms are an offshoot of daughter elements, and are formed when a radioactive element undergoes radioactive decay. The new element is the daughter element, while the initial, the former element is the parent element.
Same analogy goes for daughter atoms and parent atoms..
Radiometric dating is also called radioactive dating or even radioisotope dating. It is a technique that is used to date materials like carbon or even rocks, that has trace radioactive impurities selectively incorporated into it when they were formed.
Radiometric dating is defined as the technique, which is used to date rocks, carbon, or radioactive impurities. The rocks that consist of parent and daughter atoms are used for accurate radiometric dating.
The correct statement for the blank is:
Accurate radiometric dating typically requires that rock contains a measurable amount of parent and daughter atoms.
It can be defined as:
1. Daughter atoms are formed when the radioactive element undergoes radioactive decay. The element formed is the daughter element from which it is formed is known as the parent element.
2. A radioactive isotope is also called radioactive dating, which is used to date rocks and radioactive elements. These elements are incorporated into the elements when they are formed.
Thus, the correct answer is parent and daughter atoms.
To know more about radioactive dating, refer to the following link:
https://brainly.com/question/3444297
A 0.900-V potential difference is maintained across a 1.5m length of 2
tungsten wire that has a cross-sectional area of 0.600 mm . What is the current in the wire?
Answer:
I = 6.42 A
Explanation:
Given that,
Potential difference, V = 0.9 V
Length of the wire, l = 1.5 m
Area of cross section, [tex]A=0.6\ mm^2=6\times 10^{-7}\ m^2[/tex]
We need to find the current in the wire. Let I is current. We can find it using Ohm's law as follows :
V = IR
Where R is the resistance of the wire
[tex]I=\dfrac{V}{R}\\\\I=\dfrac{V}{\rho \dfrac{l}{A}}\\\\I=\dfrac{0.9}{5.6\times 10^{-8}\times \dfrac{1.5}{6\times 10^{-7}}}\\\\I=6.42\ A[/tex]
So, the current in the wire is 6.42 A.
Calculate the radiation dosage (in grays) for a 63‑kg person who is exposed for 5.0 s to a 3.0 Ci source of beta radiation. Assume that 100% of the radiation is absorbed and that each beta particle has an energy of 1.5×10−13 J.
Answer:
1.32142x10^-3 Gy
Explanation:
Mass m = 63kg
Time t = 5.0s
Beta energy = 1.5x19^-13J
1 Ci = 3.7x10¹⁰
3.0Ci = 3x3.7x10¹⁰
= 11.1x10¹⁰decay/s
We have a total of 11.1x10¹⁰ beta particles produced per second
The question says there is 100% absorption
Et = (11.1x10¹⁰)x5x1.5x10^-13
= 0.08325
The radiation dose = Et/m
= 0.08325/63 kg
= 0.001321428J/kg
= 0.001321428 grays
Or 1.32142x10^-3 Gy
The radiation dose of the person is 1.31 x 10⁻⁴ J/kg.
Radiation doseThe radiation does is the ratio of the total dose to the mass of the person exposed to the radiation.
3 Ci beta radiation = 3 x (3.7x10¹⁰) = 11.1 x 10¹⁰decay/s
Total beta energy absorbed in 5 sEt = (11.1x10¹⁰) x 5 x 1.5 x 10⁻¹³
Et = 8.25 x 10⁻³ J
Radiation dose of the person is calculated as follows;
Rd = Et/m
Rd = (8.25 x 10⁻³ J) / 63
Rd = 1.31 x 10⁻⁴ J/kg
Learn more about radiation dose here: https://brainly.com/question/1421857
The Doppler effect is the change in sound _____ caused by the motion of the sound source, motion of the listener, or both.
pitch
frequency
amplitude
speed
On Earth, you can lift a 10 kg object. What is the mass of that object on the moon? Is mass independent from gravity?
Explanation:
An object's weight depends on the pull of the gravitating object but the object's mass is independent of the gravity.
True or false? An electric current is a continuous flow of electric charges through a material.
A sound wave travels in a straight line at a constant speed of 660 mph. What is
the acceleration of the sound wave? Explain your answer.
Answer:
a = 0
Explanation:
The velocity of a sound wave in a straight line is 660 mph. The wave is moving with a constant velocity. It means that the change in velocity is equal to 0.
We know that acceleration of an object is equal to the change in velocity divided by time taken. But here the change in velocity is 0. As a result the acceleration of the sound wave is 0.
You want to lean your dad's ladder on a smooth wall. If the mass of ladder is 4.42 kg and coefficient of friction of the floor is 0.53, what is the minimum angle, theta-min at which the ladder does not slip? What do you think the maximum angle theta-max Could be? Sketch and label your free body diagram.
Answer:
hellllllllooooooooooooooo
A barrel of oil contains roughly 6.1x109 J. How many kW-hr is this? Answer in
units of kW-hr
Answer:
[tex]1.694*10^3KW/hr[/tex]
Explanation:
Formula:
[tex]KW/hr=E_{(change)}[/tex]
[tex]P=\frac{E}{t}[/tex]
[tex](KW)(s)=1000J[/tex]
[tex](3600)(KW)(s)=3600*1000J[/tex]
[tex]KW=3.6*10^6[/tex]
[tex]\frac{6.1*10^9}{3.6*10^6}=\frac{x}{1KW}[/tex]
[tex]1.694*10^3KW/hr[/tex]
Hope it helps
Which phrase best completes the diagram?
Drawbacks of Trade Barriers
Less consumer choice
Retaliatory trade barriers
A. Domestic jobs put at risk
B. More competition for domestic industries
O
C. Increased reliance on other countries
D. Reduced economic efficiency
Answer:D
Explanation:
just got it right
Answer:D
Explanation:
taking the test
A torque of 0.97 N m is applied to a bicycle wheel of radius 35 cm and mass 0.75 kg. Assuming the wheel can be modelled as a hoop, find the angular acceleration of the wheel.
Answer:
11 rad/s^2 approx.Explanation:
Given
torque,τ= 0.97N
radius r= 35cm to m= 0.35m
mass m= 0.75kg
Required
angular acceleration
First, we need the moment of inertial of the wheel
I=mr^2
I=0.75*0.35^2
I=0.75*0.1225
I=0.09kgm^2
Secondly, the angular moment of inertial is expressed as
a=τ/I
a=0.97/0.09
a=10.77rads/s^2
a=11 rad/s^2 approx.
What is an atom's nucleus made of?
(2 points)
protons and electrons
protons only
protons and neutrons
neutrons only
Answer:
nucleus made of protons and neutrons because the chemical atom is determined my a number
Whoever answers correctly gets brainlist!
Infared = used by police
gamma = short wavelength
radio = largest wavelength
visible = only ones we can see
Answer: police use infred waves,
radio waves have largest wave length, the
only part of the spectrum seen by humans is visible waves
gamma waves have shortest wave length
Explanation:
Which of these statements about mixtures is true? (2 points)
a
Mixtures are made up of elements bonded together.
b
Elements and compounds are types of mixtures.
c
Pure substances are made up of mixtures combined in specific ratios.
d
Mixtures are classified based on the distribution of particles in them.
Answer:A
Explanation:
Answer:
D. Mixtures are classified based on the distribution of particles in them.
Explanation:
A is wrong because mixtures are not made of elements that are bonded together chemically.
B is wrong because elements and compounds are types of pure substances.
C is wrong because pure substances are not made up of mixtures.
Please give brainliest
A primary coil of a transformer is connected to a 120V/60Hz wall outlet. The secondary coil is connected to a lamp that dissipates 60 W. How do I find the rms current in the primary coil?
Answer:
0.5Amperes
Explanation:
Using the conservation of power formula
P = VI
The power we have in this coil is given as
P = 60 watts
Then we have V = 120 watts
Such that when we put these values into the formula above we will get:
60 = 120I
Then when we divide through by 120:
I = 60/120
I = 0.5 amperes
So 0.5 amperes is the rms in the primary coil.
Someone please help asap
Question 4: If a body of mass 4 kg moves at a velocity of 25 mls and has a 2 points
completely inelastic collision with a body of mass 10 kg, the final velocities
of both the bodies is 14 m/s. Calculate the initial velocity of the body of
mass 10 kg."
Cylindrical rod has equal and opposite forces applied perpendicular to its circular ends. The forces are directed away from the rod, stretching the rod. What type of stress is this rod subject to:_________A) The rod is subject to shear stress. B) The rod is subject to tensile stress. C) The rod is subject to compressive stress. D) The rod is subject to bulk stress.
Answer:
B) The rod is subject to tensile stress
Explanation:
Tensile stress is the force induced in the body per unit area in response to externally applied force, which stretches the body.
Tensile stress is attached with tensile forces. It is makes material elongate along the axis of the applied load.
It is given as magnitude (F) of the force that is applied along an elastic rod divided by the cross sectional area (A) of the rod in a direction that is perpendicular to the applied force.
materials such as Doctile have the ability to withstand the load while brittle materials who not have the ability they fail before reaching the ultimate material strength.
