The component of the crate's weight that is parallel to the ramp is the only force that acts in the direction of the crate's displacement. This component has a magnitude of
F = mg sin(20.0°) = (15.0 kg) (9.81 m/s^2) sin(20.0°) ≈ 50.3 N
Then the work done by this force on the crate as it slides down the ramp is
W = F d = (50.3 N) (2.0 m) ≈ 101 J
The work-energy theorem says that the total work done on the crate is equal to the change in its kinetic energy. Since it starts at rest, its initial kinetic energy is 0, so
W = K = 1/2 mv ^2
Solve for v :
v = √(2W/m) = √(2 (101 J) / (2.0 m)) ≈ 10.0 m/s
When the surface of a metal is exposed to blue light, electrons are emitted. If the intensity of the blue light is increased (so the light is just brighter), what value will also increase?
A. the maximum kinetic energy of the ejected electrons
B. the number of electrons ejected per second
C. the time lag between the onset of the absorption of light and the ejection of electrons
please help!!!
So, we know that this question is about photoelectric effect.
What is photoelectric effect?
-Photoelectric effect is a phenomenon where electrons are released from a material whenever an electromagnetic radiation such as light, hits it.
-This phenomenon is first discovered by Heinrich Rudolf Hertz in 1887 whereas Albert Einstein, in 1905, resolved the conflict between the photoelectric effect and Maxwell's electromagnetic wave theory of light.
Now to your question, the intensity of light only determines the number of the electrons released, not their maximum kinetic energy because this are proportional to the light's frequency.
Also, there is no time lag detected between the entry of radiation and the emission of electrons in experiments held.
So, with letter A and C out, we can therefore conclude that the answer for this is Letter B
The correct answer is B: the number of electrons ejected per second
The Einstein photoelectric equation states that;
[tex]KE = hf - hfo[/tex]
Where
KE = kinetic energy of the ejected photo electrons
h = Plank's constant
f = frequency of incident light
fo = threshold frequency.
The kinetic energy of ejected photoelectrons depends on frequency of incident photon and not on the intensity of the incident photon.
However, the number of photoelectrons ejected per second depends on the intensity of the incident blue light.
https://brainly.com/question/9260704
Which of these events is an example of resonance?
A- a bridge collapses due to the overloading of vehicles using it.
B-A baker kneads dough by pounding it repeatedly
C-The sound of teo guitars changes from loud to soft every second
D- An ambulance siren rises and falls in frequency as it passes by you
E-An opera singer breaks a thin glass with only the use of her high frequency voice
Answer: E- An opera singer breaks a thin glass with only the use of her high frequency voice
Explanation:
Resonance is when a person is able to evoke emotions or when a person is deep in character. It is the ability to evoke memories, images and emotions.
Examples of resonance include old pictures which has emotional attachments, feel voice of a singer etc.
Therefore, the event that is an example of resonance is an opera singer breaks a thin glass with only the use of her high frequency voice.
Let's say you cut open a log of wood with an axe, what type of simple machine are you using? Does it matter how sharp it is?
yes it matters because if it's not sharp it would take all day
Answer:
an axe is a type of machine called a wedge. it does matter how sharp your axe is. if your axe is not sharp then you will have a harder time cutting wood.
Explanation:
A motor has an internal resistance of 12.1 Ω. The motor is in a circuit with a current of
4.0 Amps
What is the voltage?
Answer:
Explanation:
V = I * R
V = 4 * 12.1 = 48.4 v
The temperature of an ideal gas in a sealed 0.40m3 rigid container is reduced from 350 K to 270 K.The final pressure of the gas is 60 kPa. The molar heat capacity at constant volume of the gas is 28.0 J/(mol K). The heat absorbed by the gas is closest to
Answer:
The answer is below
Explanation:
Given that the volume (V) = 0.4 m³, temperature difference (ΔT) = 270 K - 350 K = -80 K, pressure (P) = 60 kPa = 60000 Pa, R = 8.314 J/molK
Since we have constant volume, we can use the final state parameters to calculate the number of moles using the ideal gas law:
[tex]PV=nRT\\\\n=\frac{PV}{RT} =\frac{60000*0.4}{8.314*270} =10.69\ moles[/tex]
Given that the molar heat capacity at constant volume ([tex]C_v[/tex]) = 28.0 J/(mol K), the heat absorbed (Q) is:
[tex]Q=nC_v\Delta T=10.69*28*(-80) = -23945.6\ J\\\\Q=-23.95\ kJ[/tex]
Q ≈ -24 kJ
What is the three-body problem? Explain at a level so an 8th grader could understand
Answer:
In physics and classical mechanics, the three-body problem is the problem of taking the initial positions and velocities (or momenta) of three point masses and solving for their subsequent motion according to Newton's laws of motion and Newton's law of universal gravitation.[1] The three-body problem is a special case of the n-body problem. Unlike two-body problems, no general closed-form solution exists,[1] as the resulting dynamical system is chaotic for most initial conditions, and numerical methods are generally required.
Hope this answer is right!
How long does it take you to create 200 Watts of power if you use 1000 J of
work?
Answer:200,000
Explanation:
p=w/t
200=1000/t
t=200*1000
time=200,000
how can you account for the differences in the entropies of combination of methyl propane (-1465J/mol K) and butane (1465J/mol K)
Explanation:
The change in entropy is a measure of temperature. When the temperature of a compound or a system increases, there will be more randomness in the system.
The boiling point is directly related to the number of carbon atoms but is indirectly proportional to the branching in a hydrocarbon.
Butane and methyl propane, both have 4 carbon atoms.
But, butane has 4 carbon atoms in a straight chain while methyl propane has 3 carbon atoms in a straight chain and 1 methyl substituent which makes it a branched hydrocarbon.
Thus, the boiling point of methyl propane will be less than the butane. Likewise, the pattern in entropies will be seen.
What's the meaning of longitudinal?
Answer:
A longitudinal study is a research design that involves repeated observations of the same variables over short or long periods of time. It is often a type of observational study, although they can also be structured as longitudinal randomized experiments.
Explanation:
Which variable is represented by the following symbol? λ
a. Wavelength
b. Amplitude
c. Frequency
d. Velocity
Answer:
A
Explanation:
Wavelength is represented by lambda
A 50.0 kg object is moving east at an unknown velocity when it collides with a 60.0 kg stationary object. After collision, the 50.0 kg object is traveling at a velocity of 6.0 m/s 50.0degree N of E and the 60.0 kg object is traveling at a velocity of 6.3 m/s 38degree S of E.
What was the velocity of the 50.0 kg object before collision?
p=m•v is the formula.
The principle of conservation of momentum states that:
momentum before collision = momentum after collisionMomentum = mass * velocityMomentum before collision:
Velocity of 50.0 kg object = v m/s
Momentum of 50.0 kg object = 50 * v
Momentum after collision:
Velocity of the 50.0 kg object = 6.0 m/s 50.0degree N of E
Velocity of the 60.0 kg object = 6.3 m/s 38degree S of E.
Momentum of 50.0 kg object = 50 * 6 = 300 kgm/s
Momentum of 50.0 kg object = 60 * 6.3 = 378 kgm/s
Total momentum after collision = 678 kgm/s
From the principle of conservation of momentum:
50 kg * v = 678 kgm/s
v = 678 kgm/s / 50 kg
velocity, v = 13.56 m/s
Therefore, the velocity of the 50.0 kg object before collision was 13.56 m/s.
Learn more about conservation of momentum at: https://brainly.com/question/7538238
please helpppp... thank u ❤️
Answer:
For Ryan:
[tex]at \: highest \: point : v = 0 \\ velocity = 0 \: {ms}^{ - 1} [/tex]
For the football kicked:
[tex]s = ut - \frac{1}{2} g {t}^{2} \\ for \: range : s = 0 \\ u \sin( \theta) = \frac{gt}{2} \\ t = \frac{2u \sin(\theta) }{g} \\ range(x) = ut \\ x = \frac{ {2u {}^{2} \sin(\theta) }^{} }{g} \\ \frac{50 \times 9.8}{ {2318.9}^{} } = \sin(\theta) \\ \\but \: 0 = u \sin(25) - 2 \times 9.8 \times 50 \\ u = 2318.9 \: {ms}^{ - 1} \\ \theta = 12.2 \degree[/tex]
Answer:
the highest point for the first question is 0 meters per second
the answer for question 2 is 45 degrees
How are galaxies named?
Answer:
Some galaxies are given descriptive names (e.g. "Andromeda", "Whirlpool") if they are particularly distinctive in location or appearance. But most galaxies are known from their designation in a catalogue. One of the earliest catalogues of objects in the sky was made by Charles Messier.
What is the sum of a systems potential and kinetic energy is equal to?
a. Total Energy
b. Mechanical Energy
c. Thermal Energy
d. Hyper Energy
Answer:
Explanation:
TE = KE + PE which is total energy available to a system is equal to its potential energy plus its kinetic energy, and that total energy will remain throughout the entire "trip", whatever it might be. So a is your answer.
Which state has the most fixed shape?
O A. Gas
O B. Solid
O C. Liquid
O D. Plasma
Answer: Liquid
“A substance will take on the shape of an open container if it is a Liquid. Explanation: The major state of matter are solid, liquid and gas. Liquid usually have a definite volume.”
Answer:
solid
Explanation:
Solids are fixed and solid.
5. A wire, resistance 23.6 carries a current. 5.9 A. What is the
potential difference across the wire?
a. V = 139 V
c. V=4V
b. V = 17.7 V
d. V = 0.25 V
Answer:
d
Explanation:
Answer:
B
Explanation:
A 75kg hockey player is skating across the ice at a speed of 6.0m/s. What is the magnitude of the average force required to stop the player in 0.65s?
Answer:
692.31 N
Explanation:
Applying,
F = ma............... Equation 1
Where F = Average force required to stop the player, m = mass of the player, a = acceleration of the player
But,
a = (v-u)/t............ Equation 2
Where v = final velocity, u = initial velocity, t = time.
Substitute equation 2 into equation 1
F = m(v-u)/t............ Equation 3
From the question,
Given: m = 75 kg, u = 6.0 m/s, v = 0 m/s (to stop), t = 0.65 s
Substitute these values into equation 3
F = 75(0-6)/0.65
F = -692.31 N
Hence the average force required to stop the player is 692.31 N
what current flows between a voltage of 120v across a resistance of 30Ω?
Answer:
4 amp
Explanation:
From ohm's law,
V=IR
so,
I=V/R
I=120/30
I=4amp ans..
if a car is taken from the garage driven for 100km before returning to the garage after 2 hours what is it average speed?
Answer:
50km/h
Explanation:
Average Speed = Distance/Time
100km/2h = 50km/h
PLEASE HELP WITH THIS QUESTION
What of Newton's 3 laws is represented in this picture?
Answer:
The first law states that an object at rest will stay at rest, and an object in motion will stay in motion unless acted on by a net external force. Mathematically, this is equivalent to saying that if The second law states that the rate of change of momentum of a body over time is directly proportional to the force applied, and occurs in the same direction as the applied force. the net force on an object is zero, then the velocity of the object is constant. The third law states that all forces between two objects exist in equal magnitude and opposite direction: if one object A exerts a force FA on a second object B, then B simultaneously exerts a force FB on A, and the two forces are equal in magnitude and opposite in direction
Explanation:
Convert 162 km/h into m/s.
Answer:
45 m/s
Explanation:
162 / 3.6 = 45 m/s
Divide by 3.6 to convert km/h to m/s.
Q1. What is the mass of a ball that has a kinetic energy of16 J and it is traveling at 4 m/s?
Q2. What is the kinetic energy of a soccer ball which has a mass of 1 kg and is kicked with a velocity of 10 m/s?
Q3.exercise ball is on a table 2 m above the ground. What is the mass of the ball if it has a GPE of 40 ?
Q4.What is the gravitational potential energy (GPE) of a 2 kilogram book that is 20 meter above the ground?
Answer:
Explanation:
Kinetic Energy has a formula of
[tex]KE=\frac{1}{2}mv^2[/tex] and
Potential Energy has a formula of
PE = mgh. The first 2 problems use the KE formula and the next 2 use the PE formula.
Q1. KE = 16 and v = 4 m/s:
[tex]16=\frac{1}{2}m(4)^2[/tex] and
[tex]\frac{2(16)}{16}=m[/tex] so
m = 2 kg
Q2. mass = 1 kg and v = 10 m/s:
[tex]KE=\frac{1}{2}(1)(10)^2[/tex] so
KE = 50 J
Q3. PE = 40, h = 2, g = 9.8:
40 = m(9.8)(2) and
[tex]\frac{40}{(9.8)(2)}=m[/tex] so
m = 2.0 kg
Q4. mass = 2 kg, g = 9.8 m/s/s, h = 20:
PE = 2(9.8)(20) so
PE = 392 J
**I completely disregarded the rules for sig fig's because your numbers were very inexact**
why would the planets move in a straight path if there was no gravitational energy from the sun
Explanation:
The sun's gravitational force is very strong. If it were not, a planet would move in a straight line out into space. The sun's gravity pulls the planet toward the sun, which changes the straight line of direction into a curve. This keeps the planet moving in an orbit around the sun
Answer and Explanation:
The planets would move in a straight path since there would be no source that will be acting upon them (if the sun wasn't there).
Gravitational pull is the amount of force that an object emits. Due to the Sun having a larger mass and a larger gravitational pull, the planets orbit around it.
If, for example, a house was bigger than everything, including planets and stuff, those things would orbit around the house.
A real life example is the moon orbiting Earth. The Earth has a greater magnitude and mass, so it is able to pull the Moon.
Right now the Sun is the external force, as its gravitational pull is moving the planets around. IF the sun was to magically disappear, the planets won't follow an orbit anymore, since there isn't a gravitational pull on them. This leads them to going in a straight line for possibly a couple years.
Eventually, the planets will stop going in a straight line and start to orbit each other, leading to the planets eventually crashing.
External Force = Sun's gravitational pull because of bigger mass
The planets themselves were created after the sun (though some minerals were created before the sun, but that's minerals and not the planet entirely). The sun gives the planet's their motion. The planets, however (though I'm not sure about mercury and Venus) are going super fast, fast enough to where they aren't being pulled into the sun, but not fast enough to go out of orbit.
If the sun goes out magically, the planets, actually yes will continue orbit due to them being in that motion at such a fast rate, but eventually when they are supposed to turn again, (like, to another part of the sun), the would go straight. Eventually, the will get into the orbit of something else and start going around that object's orbit, most likely outcome being that they crash.
The excess force from no gravitational pull will make the planets go in a straight path. Since nothing is acting upon it, the planets would move in a straight line. Imagine if you were on those spinning circle things, and then let go. You would go around it for like a second and then go immediately straight in one direction.
#teamtrees #PAW (Plant And Water)
As an IT technician for your company, you have been notified that the Windows domain does not seem to be functioning properly. Being familiar with domains, you are fairly confident you know what the issue is. But just to be safe, you take the applicable time to gather additional information and to identify what, if anything, has changed.
Which of the following is the BEST next step?
A. Determine the appropriate fix.
B. Create a hypothesis.
C. Implement the fix.
D. Identify what has changed.
E. Gather information.
Answer: Create a hypothesis
Explanation:
From the information given, information has been gathered and the identification to ascertain if there's a change. Then, an hypothesis has to be created in order to know what the problem is.
One has to carry out some research in order to know what went wrong and should also validate the hypothesis by consulting with ones peers. By doing this, the most likely causes of the issues will be gotten.
give an example of a body with uniform acceleration
Answer:
A ball rolling down the slope.
A bicycle rider is riding the bicycle on tthe slope where both pedals are engaged.
Q) A farmer moves along the boundary of a
square field of side 10 min 40 s .What will
be the magnitude of displacement of the
farmer at the end of 2 minutes 20 seconds
from his initial position?
Loops spaced further apart create a stronger electromagnet. True or False
Answer:
False
Explanation:
Electromagnetic strength is inversely proportional to separation distance
Amelia is doing an experiment in which she is
going to burn various solid chemicals to see the
colors of flames they produce. For this laboratory
experiment, what types of safety precautions
should she take?
tie hair back
leave open flame unattended to get a drink
only burn the amount of chemicals as
directed by the lab procedure
put out the flame with water from the eyewash
station
Answer:
tie hair back
only burn the amount of chemicals as
directed by the lab procedure
Explanation:
The correct safety precautions for Amelia to take from the options would be to tie her hair back and to only burn the amount of chemicals recommended by the lab procedure.
With her hair left flowing freely, Amelia runs the risk of the hair catching flame while trying to burn the chemicals according to the procedure. Hence, tying her hair up into one neat bunch will limit the risk of it catching fire while working in the lab.
Also, burning less or more than the amount of chemicals recommended by the procedure may be dangerous or hinder Amelia from getting the right result.
Answer:
1,3
Explanation:
just did it
A piece of iron has a mass of 30 g and its volume is 6.2 cm3. What is its density?
Answer:
Density = 4.84 g/cm³
Explanation:
Given the following data;
Mass = 30 g
Volume = 6.2 cm³
To find the density of the piece of iron;
Density can be defined as mass all over the volume of an object.
Simply stated, density is mass per unit volume of an object.
Mathematically, density is given by the equation;
[tex]Density = \frac{mass}{volume}[/tex]
Substituting into the equation, we have;
[tex]Density = \frac{30}{6.2}[/tex]
Density = 4.84 g/cm³
5. What type of chemical reaction is shown?
1 point
2 AgNO3 + CuCl2
-
2 AgCl + 2 Cu(NO3)2
Synthesis
Decomposition
Singe Replacement
Double Replacement
Combustion
Answer:
double Replacement
Explanation:
The mutual replacement of radical and ions between the two compounds or molecules is called double replacement.
General equation : AB+CD = AD +B
