The diagram shows a model of an atom. Who first proposed this model?
A. Bohr
B. Thomson
C. Rutherford
ОО
D. Dalton
A.Bohr
His model postulated the existence of energy levels or shells of electrons. Electrons could only be found in these specific energy levels; in other words, their energy was quantised, and couldn’t take just any value. Electrons could move between these energy levels but had to do so by either absorbing or emitting energy.
A. Bohr!
This answer is correct because I read the information.
Laura is a star runner of the school's track team. During a trial, her speed was measured to be 9.80 m/s. If Laura's mass is 45.2 kg, her kinetic
energy during the trial was
Answer:
KE = 2.17 E3 J
Explanation:
m = 45.2 kg
v = 9.8 m/s
KE = 1/2mv^2
KE = [(45.2 kg)(9.8m/s)^2]/2
KE = 2.17 E3 J
Which frequency would be the third harmonic in a series for an open-pipe resonator if the fundamental is 440 Hz
Answer:
1320 Hz
Explanation:
The third harmonic is given as 3fo, where fo is the fundamental frequency.
The fundamental frequency is the lowest frequency that can occur in a pipe. In an open pipe, both even and odd harmonics occur which are multiples of the fundamental frequency fo. Hence the harmonics in an open pipe are; 2fo, 3fo,4fo..... etc.
For the third harmonic; 3fo = 3 (440 Hz) = 1320 Hz
pls help me w this, I've been doing this since 5 minutes ago
Answer:
t=0.0625s
Explanation:
F=number of swings/time taken
DATA
Frequency=4.0Hz
number of swings from Q to R
=1/4
time taken=?
Frequency=number of swings/time taken
make t the subject of the formula
t=n/f
substitute the given date
t=0.25/4.0
t=0.0625s
option A is collect
PLEASEEE HELPPP!!!
A mover slides a refrigerator weighing 650 N at a constant velocity across the floor
a distance of 8.1 m. The force of friction between the refrigerator and the floor is
230 N. If the work was done in 55 seconds, what is the power of the mover?
Answer:
very strong
Explanation:
the answer is something
!!!!!
While following directions on a treasure map, a person walks 45.0 m south, then turns and
walks 7.50 m east. What is the direction of the straight line that the treasure hunter could have
walked directly from the starting to reach the same spot?
(1 Point)
9.5° south of east
9.5° east of south
21° south of east
21° east of south
Answer:
46 m at 9.5 degrees east of south
Explanation:
Speed, Velocity, and Acceleration Escape Room.
Enter the correct 4 digit code (no spaces
Answer:1342
Explanation:
please answer asignment due today
Answer:
Give me some time okkkk
Physical values in the real world have two components: magnitude and
Answer:
Dimension.
Explanation:
obtain the temp. at which the reading of Fahrenheit is double of that in Celsius scale.
Answer:
320 degrees fahrenheit and 160 degrees celcius
Explanation:
there's a formula that i definately don't remember but it exists
4 pleasee i have to submit in 10 minutes
Answer:
True
Explanation:
which internal energy source produces heat by converting gravitational potential energy into thermal energy
Ethics are deliberately learned from the family. Please select the best answer from the choices provided
Answer:
what are the choices provided?
Explanation:
Answer:
True
Explanation:
On Edg
An object is falling from a height of d and reaches a final velocity of vf. Calculate velocity when the object has fallen a distance d/2.
Answer:
The final velocity, [tex]v_{f}[/tex], is gd.
Explanation:
The condition here is a free falling object. Thus from the third equation of motion under free fall, we have;
[tex]v_{f}[/tex] = [tex]v_{i}[/tex] + 2gs
where [tex]v_{f}[/tex] is the final velocity of the object, [tex]v_{i}[/tex] is the initial velocity of the object, g is the gravitational force and s is the height.
Since the object falls from a height of d, then [tex]v_{i}[/tex] = 0 m/s, and s = d.
So that;
[tex]v_{f}[/tex] = 0 + 2gd
= 2gd
[tex]v_{f}[/tex] = 2gd
When the distance is [tex]\frac{d}{2}[/tex], [tex]v_{i}[/tex] = 0 m/s.
Then;
[tex]v_{f}[/tex] = 2g[tex]\frac{d}{2}[/tex]
[tex]v_{f}[/tex] = g x d
When the object falls through the height [tex]\frac{d}{2}[/tex], then the final velocity is gd.
what is it that makes a magnet different from a piece of iron that is not mangetic?
Answer:
Under normal conditions, a magnetic material like iron doesn't behave like a magnet because the domains don't have a preferred direction of alignment. On the other hand, the domains of a magnet (or a magnetized iron) are all aligned in s specific direction.
which is the best evidence that continents that are now separated were once
joined?
A. continents that were once joined now have similar climates
B. identical plant and animal fossils are found on continents that are now separated
C. the cultures of the people on separated continents have similar languages
D. the migratory patterns of wildlife on separated continents are similar
A pressure sensor inside of a mixing tank is designed to turn red when the pressure inside the tank exceeds 1.9 kPa. If the sensor is a square, 10 cm on each side, how great a force must be exerted on the sensor in order for it to turn red?
Answer:
19 N
Explanation:
From the question given above, the following data were obtained:
Pressure (P) = 1.9 kPa
Length (L) = 10 cm
Force (F) =?
Next, we shall convert 1.9 KPa to N/m². This can be obtained as follow:
1 KPa = 1000 N/m²
Therefore,
1.9 KPa = 1.9 KPa × 1000 N/m² / 1 KPa
1.9 KPa = 1900 N/m²
Thus, 1.9 KPa is equivalent to 1900 N/m².
Next, we shall convert 10 cm to m. This can be obtained as follow:
100 cm = 1 m
Therefore,
10 cm = 10 cm × 1 m / 100 cm
10 cm = 0.1 m
Thus, 10 cm is equivalent to 0.1 m
Next, we shall determine the area of the square. This can be obtained as follow:
Length (L) = 0.1 m
Area of square (A) =?
A = L²
A = 0.1²
A = 0.01 m²
Thus, the area of the square is 0.01 m².
Finally, we shall determine the force that must be exerted on the sensor in order for it to turn red. This can be obtained as follow:
Pressure (P) = 1900 N/m²
Area (A) = 0.01 m²
Force (F) =?
P = F/A
1900 = F / 0.01
Cross multiply
F = 1900 × 0.01
F = 19 N
Therefore, a force of 19 N must be exerted on the sensor in order for it to turn red.
Two lamps rated 60W; 240V and 100W, 240Vrespectively are connected in series to a 240V power source. Calculate;
a) The resistance of each lamp.
b) The effective resistance of the circuit.
c) The current passing the lamps. pls answer correctly
Answer:
See the answers below.
Explanation:
The total power of the circuit is equal to the sum of the powers of each lamp.
[tex]P=60+100\\P=160 [W][/tex]
Now we have a voltage source equal to 240 [V], so by means of the following equation we can find the current circulating in the circuit.
[tex]P=V*I[/tex]
where:
P = power [W]
V = voltage [V]
I = current [amp]
[tex]I = P/V\\I=160/240\\I=0.67 [amp][/tex]
So this is the answer for c) I = 0.67 [amp]
We know that the voltage of each lamp is 240 [V]. Therefore using ohm's law which is equal to the product of resistance by current we can find the voltage of each lamp.
a)
[tex]V=I*R[/tex]
where:
V = voltage [V]
I = current [amp]
R = resistance [ohms]
Therefore we replace this equation in the first to have the current as a function of the resistance and not the voltage.
[tex]P=V*I\\and\\V = I*R\\P = (I*R)*I\\P=I^{2}*R[/tex]
[tex]60 = (0.67)^{2}*R\\R_{60}=133.66[ohm] \\and\\100=(0.67)^{2} *R\\R_{100}=100/(0.66^{2} )\\R_{100}=225 [ohm][/tex]
b)
The effective resistance of a series circuit is equal to the sum of the resistors connected in series.
[tex]R = 133.66 + 225\\R = 358.67 [ohms][/tex]
a 5.00 kg plane is speeding up on the ground with an applied force of 706 N. If the net force is 450 N, what would be the force due to air resistance
Answer:
The force due to air resistance is 256 N.
Explanation:
Given;
mass of the plane, m = 5 kg
applied force on the plane, Fa = 706 N
the net force on the plane, ∑F= 450 N
Let the force due to air resistance = Fr
The net force on the plane is given as;
Net force = applied force - force due to air resistance
∑F = Fa - Fr
Fr = Fa - ∑F
Fr = 706 - 450
Fr = 256 N.
Therefore, the force due to air resistance is 256 N.
Help please ASAP !! Thanks
Answer:
I think its C
Explanation:
If there are oncoming cars to the left of you and a child on a bike to the right, what is the correct action to take
Answer:
Give the child a lot of room to your side, which may mean moving closer to the oncoming vehicles.
Explanation:
I majored in Physics.
what must be true if a waves wavelength is short ?
Answer: So, if the wavelength of a light wave is shorter, that means that the frequency will be higher because one cycle can pass in a shorter amount of time. ... That means that longer wavelengths have a lower frequency. Conclusion: a longer wavelength means a lower frequency, and a shorter wavelength means a higher frequency!
If the wavelength of a wave is short. It is true that the wave will have a lower frequency. A longer wavelength denotes a lower frequency.
What is a wave?A wave is a phenomenon that flows across a material medium without leaving any lasting mark.
Frequency is defined as the number of cycles per second. The time to make one complete cycle is the frequency and the distance between successive crests of a wave is the wavelength.
Thus, a shorter wavelength of a light wave signifies a greater frequency since one cycle may pass in a shorter amount of time. Longer wavelengths have a lower frequency.
Hence a longer wavelength denotes a lower frequency, whereas a shorter wavelength denotes a higher frequency.
To learn more about the wave refer to the link;
brainly.com/question/3004869
.
A student used a video camera to record another student dropping a marble through water in a graduated cylinder. The students watched the video in slow motion and made the observations shown below.
marble, drop, experiment, marble, graduated, cylinder, water, 1, speed, increases, 2, speed, decreases, 3, speed, is, constant,
During which part or parts of the marble’s fall did the marble experience unbalanced forces?
Answer:
Parts 1 and 2 only is the best answer.
Explanation:
Hope this helps!
Answer: 1 and 2
Explanation:
What is the tangential velocity of a record player which makes 11 revolutions in 20 seconds?
Velocity is defined as rate of change of displacement wit respect to time.
tangential velocity is (11/10)πr , where r is radius of circular track.
Since, tangential velocity is, [tex]=\frac{distance}{time}[/tex]
In one revolution, distance travelled is circumference of circular track.
If radius of circular track is r , then distance travelled in one revolution is, = 2πr
So, 11 revolutions = 11(2πr) = 22πr
Time taken = 20 second
So, tangential velocity = 22πr/20 = (11/10)πr meter per second.
Learn more:
https://brainly.com/question/14401457
m=20kg F=10N d=25m
Work done=?
w=f×d
w=10N×25m
w=250Nm
A car changes chemical energy from fuel into thermal energy and ________ energy.
Answer:
Mechanical energy
Explanation:
A car changes chemical energy from fuel into thermal energy and mechanical energy.
Mechanical energy can be defined as the type of energy that is possessed by an object due to its motion or position. Mechanical energy is the sum of potential energy and kinetic energy, that is, the sum of energy in motion and stored energy. Examples of mechanical energy includes driving a car, riding a bicycle, listening to music etc.
Types of mechanical energy
1. Motion energy (kinetic energy)
2. Stored energy(potential energy)
Mechanical energy = Kinetic energy + Potential energy
State ten reasons why students in Uganda need to study physics. Use exampes of the possible technological advancements which can be made using the knowledge of physics
HELP ASAP!! WILL TRY TO GIVE BRAINLIEST
Explain how receptor-mediated endocytosis is more specific than pinocytosis or phagocytosis
Answer:
it selects what molecules to engulf, whereas pinocytosis or phagocytosis engulf anything in the vicinity
Trust!
1. While riding a chairlift, a 55-kg skier is raised a vertical distance of 370 m. What is the total change in the skier's gravitational potential energy
Answer:
199,430Joules
Explanation:
Gravitational potential energy is the energy possessed by a falling object due to virtue of its position.
gravitational potential energy = mass * acceleration due to gravity * height
gravitational potential energy = 55 * 9.8 * 370
gravitational potential energy = 539 * 370
gravitational potential energy = 199,430
Hence the total change in the skier's gravitational potential energy is 199,430Joules
ANSWER:
99,430 Joules (in multiple choice question sometimes appear as 200,000J)
Explanation:
Gravitational potential energy is the energy possessed by a falling object due to virtue of its position.
gravitational potential energy = mass * acceleration due to gravity * height
gravitational potential energy = 55 * 9.8 * 370
gravitational potential energy = 539 * 370
gravitational potential energy = 199,430
Hence the total change in the skier's gravitational potential energy is 199,430 Joules (or 200,00J)
please heart!VVV or stars :D vvv
You go to the store and buy 3 apples. Each apple has a mass of 4.66 grams. What is the total mass of apples you bought.
Remember the difference between a counted and a measured number.
NEEP HELP!
Taking Finals
its 13.98. it's simple multiplication 3* 4.66= 13.98