Answer:
392 N
Explanation:
Mass of the ball=40kg
g=9.8m/s^2
Weight(w)=40×9.8
=392N
We can use energy principles to make ____ predictions.
A wave with a frequency of 20 Hz has a wavelength of 4 meters. At what speed will this wave travel?
Answer: v= 80 m/s
Explanation: speed = wavelength×Frequency
How will the boat be affected if it enters a part of the river where the current is moving south at 2 m/s?
Answer:
The boat is most likely to crash or sink since the water will be very rapid and pacing.
A closed system consists of a pendulum that is swinging back and forth. If the kinetic energy of the pendulum INCREASES, what else must happen to the energy of the system?
A. Its gravitational potential energy must decrease.
B. Its total mechanical energy must decrease.
C. Its gravitational potential energy must increase.
D. Its total mechanical energy must increase..
Answer:
Both C and D are true.
Energy goes from total kinetic to total gravitational
If Kinetic energy increases then the gravitational energy at its maximum displacement will also increase.
E (total) = PE + KE at any point of the motion
Answer: it’s A
Explanation: I just took the test
How much power is needed to move a 2000 kg mass from the bottom of the 150 m talk great pyramid in Egypt up a ramp if the ramp has a mechanical advantage of 4 and it takes the workers 30 minutes to move the mass?
Answer:
How Heavy? More than 2,300,000 limestone and granite blocks were pushed, pulled, and dragged into place on the Great Pyramid. The average weight of a block is about 2.3 metric tons (2.5 tons).
Explanation:
what is a magnetic field? how could you visualize one?
Answer:
A magnetic field is what causes gravity basically
Explanation:
To visualize a magnetic field think of 2 ovals on the opposite side of each-other, like one oval on the top of a circle and one on the bottom, that's how id visualize it
A ball starts from rest and accelerates at a constant rate of 1.0m/s to a final velocity of
5.5m/s. How long did it take for this ball to reach its final velocity?
Answer:
Time taken to reach final velocity = 5.5 second
Explanation:
Given:
Initial velocity (Starting from rest)(u) = 0 m/s
Acceleration of ball (a) = 1 m/s²
Final velocity (v) = 5.5 m/s
Find:
Time taken to reach final velocity
Computation:
Using first equation of motion;
v = u + at
where,
v = final velocity
u = initial velocity
a = acceleration
t = time taken
5.5 = 0 + (1)(t)
5.5 = t
Time taken to reach final velocity = 5.5 second
What are the methods of plotting the magnetic field?
Answer:
The method explained below shows the plotting of magnetic field lines with the help of a small compass needle:
Procedure:
1. With the help of some board pins, fix a sheet of paper on a drawing board.
2. At point 1 as seen in the below figure, place a small compass needle. From the top of the needle, mark two pencil dots at exactly two ends of the needle.
3. Move the needle to the compass to point 2 so that one end of the needle coincides with the second pencil dot.
4. The process of moving the compass needle to points 3, 4, 5… is continued in order to get a few dots.
5. When various dots are joined, a straight line is obtained.
6. Hence, one line of magnetic field of earth is traced.
Starting from a different point, the process is repeated and another line of magnetic field is traced out. This way a few several lines of magnetic field can be traced out. Every line is required to be labelled with the help of an arrow from the south pole of the needle towards the north pole to represent the direction of the magnetic field. The figure below depicts several magnetic lines that are obtained this way.
Answer:
please give me brainlist and follow
Explanation:
Magnetic fields can be mapped out using small plotting compasses : place the plotting compass near the magnet on a piece of paper. mark the direction the compass needle points. move the plotting compass to many different positions in the magnetic field, marking the needle direction each time.
how can we improve natural resources
Answer:
reduce, reuse, and recycle paper,plastic, electricity, glass, fiber
Victor put a match on a balance and found that its mass was 6.0 grams. Then he lit the match and put it out after a few seconds.
He put the partially burned match on the balance again. This time, its mass was 4.5 grams.
Which of the following best explains what happened as the match burned?
A.
Some of the mass was destroyed by the fire.
B.
The matter moved to a different part of the match.
C.
Some of the matter changed from solid to gas and went into the air.
D.
The mass of the match combined with the mass of the fire.
Answer:
b
Explanation:
13.2.2 7+6 - 9(-2)+(-3)
Answer:
34.27 is the answer
How old is Earth and what do we use to keep track of major Earth events?
What is the amount of electrical potential is measured by?
A. ampere
B. watt
C. volts
Answer:
voltmeter (C. Volts)
Explanation:
The amount of electrical potential is measured by voltmeter. Electrical potential is the amount of work needed to move a unit electric charge from a reference point to the specific point in an electric field. The SI unit of electrical potential is Volt.
brainliest?
Answer:
Volts
Explanation:
A person starts running from 2 m/s to 6 m/s in 2 seconds.
Calculate the person's acceleration.
Var
Variables:
Solve:
F
Formula:
Answer:
2 m/s²
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 2 m/s
Final velocity (v) = 6 m/s
Time (t) = 2 s
Acceleration (a) =?
The acceleration of the person can be obtained as follow:
v = u + at
6 = 2 + (a×2)
6 = 2 + 2a
Collect like terms
6 – 2 = 2a
4 = 2a
Divide both side by 2
a = 4 / 2
a = 2 m/s²
Therefore, the acceleration of the person is 2 m/s²
Explain why a sound becomes louder as you move closer to the source of the sound.
Answer:
The wavelength of frequency of the sound are closer to each other
Or
The frequency of the sound increases as it moves towards you
50 POINTS!!! PLEASE ANSWER CORRECTLY!
Who patented the first radio transmitter?
A.) Maxwell
B.) Hertz
C.) Tesla
D.) Watson-Watt
(This is so stu.pid because Marconi invented it but my science teacher doesn't uNdErStAnD that -.-)
what is the order of magnitude for 3.9×10¹²
A mass of 3.6 kg oscillates on a horizontal spring with a spring constant of 160 N/m. When the mass passes the equilibrium point its speed is 5.2 m/s. d. What is the maximum displacement of the mass?
Answer:
x = 0.78 m = 78 cm
Explanation:
Applying the law of conservation of energy to the spring-mass system, we can write the following equation:
[tex]Kinetic\ Energy\ at\ Mean\ Position= Potential\ Energy\ at\ extreme\ position\\\frac{1}{2}mv^2 = \frac{1}{2}kx^2\\\\x^2 = \frac{mv^2}{k}\\\\x = \sqrt{\frac{mv^2}{k} }[/tex]
where,
x = maximum displacement = ?
m = mass = 3.6 kg
v = speed at mean position = 5.2 m/s
k = spring constant = 160 N/m
Therefore,
[tex]x = \sqrt{\frac{(3.6\ kg)(5.2\ m/s)^2}{160\ N/m} }\\\\[/tex]
x = 0.78 m = 78 cm
what is the relationship between harmonics and resonance frequency in a piano
There is direct relationship between harmonics and resonance frequency.
A harmonic is a wave with a frequency that is a positive integer multiple of the frequency of the original wave whereas, resonance frequency is the frequency at which the oscillation reaches to its maximum point. The lowest resonant frequency is known as the fundamental, while on the other hand, the higher resonant frequencies are called overtones. All resonant frequencies are multiples of the fundamental, and are called harmonics. So we can conclude that there is a direct relationship between harmonics and resonance frequency.Learn more about harmonic here: https://brainly.com/question/17315536
Learn more: https://brainly.com/question/23262887
a bullet of mass 120g is fired horizontally into a fixed wooden block with a speed of 20m\s. The bullet is brought to rest in a wooden block in 0.1secs by a constant resistance
calculate the;(I) magnitude of the resistance
(ii) distance moved by the bullet in the wood
Answer:
1) F = 24 N
2) Distance = 1 m
Explanation:
We are given;
Mass; m = 120 g = 0.12 kg
Initial velocity; u = 20 m/s
Final velocity; v = 0 m/s since it came to rest.
Time; t = 0.1 s
We can calculate acceleration from Newton's first equation of motion;
a = (v - u)/t
a = (0 - 20)/0.1
a = -200 m/s²
1) magnitude of the resistance will be;
F = ma
F = 0.12 × (-200)
F = -24 N
Since, we are dealing with the magnitude, we will take the absolute value. Thus, F = 24 N
2) To find the distance moved by the bullet, we know that;
Distance = Average speed × time
Thus;
Distance = ((v + u)/2) × t
Distance = ((0 + 20)/2) × 0.1
Distance = 1 m
A 12kg aluminum box is sliding along a horizontal steel surface while experiencing a rightward applied force of 60N. The box has a displacement of 20m. What is the Net Force acting on the box? *
A.)60N
B.)117.72N
C.)4.67 N
D.)-55.33N
How will a ray of light traveling parallel to the principle axis of a concave mirror be reflected back
Answer:
It will be reflected to the principal focus of the concave mirror
Explanation:
This is because all rays parallel and close to the principal axis of a concave mirror get reflected to the principal focus of the mirror.
For a ray to be parallel to the mirror, it must be coming from an infinite distance.
So, using the mirror formula,
1/u + 1/v = 1/f where u = object distance from mirror, v =image distance form mirror and f =focal length of mirror.
Since u = infinite distance = ∞
1/u + 1/v = 1/f
1/∞ + 1/v = 1/f
0 + 1/v = 1/f
1/v = 1/f
v = f
So, the image is at the principal focus.
So, the ray of light parallel to the principal axis of the concave mirror is reflected to the principal focus of the concave mirror.
Work out the area of a rectangle with base, b=20mm and perimeter, p=50mm
Answer:
100mm²
Explanation:
the other side: (50 - 20 × 2) ÷ 2 = 5
5 × 20 = 100
Answer:
Subtract given lengths: 50 - 20 = 30
Divide by 2 since there are 2 missing sides that need a length: 30 divided by 2 = 15
With the given side lengths multiply all of them to get your area.
15 x 20 = 300 is your area I am pretty sure.
1. How can you explain the sound has energy?
Answer:
Sound energy is produced when an object vibrates. The sound vibrations cause waves of pressure that travel through a medium, such as air, water, wood or metal. Sound energy is a form of mechanical energy.
Explanation:
What do oxygen and bromine have in common ?
Answer:
oxygen and bromine are both highly reactive. they are also both nonmetals
Manny walked a total of 3 miles. The reference point used to calculate the total distance that he walked was the same as the ending point. Which describes where Manny most likely walked?
Correct question:
Manny walked a total of 3 miles. The reference point used to calculate the total distance that he walked was the same as the ending point. Which describes where Manny most likely walked?
a. from the bottom of a hill to the top
b. on a circular nature trail
c. on a sidewalk from his house to the mall
d. from the beginning of a straight track to the end
Answer:
b. on a circular nature trail
Explanation:
As it is mentioned that Manny that his reference point from where she started is same as ending point meaning that she moved in a circular path making point B correct answer.
Answer:
on a circular nature trail
Explanation:
Can anyone help me with this question please
I’ll mark as brainliest
No links.
the transverse Wave which is Answer:2
Answer:
1
Explanation:
amplitude is the maximum distance from the rest of the particles. amplitude is thus measured from the rest position to the peak of a crest or of a trough.
as seen below, graph 1 has an amplitude of 1 while both graph 2 and 3 has an amplitude of 2.
What is the quality of the sound of an ambulance's siren when it moves toward a stationary hearer? What is the quality of the sound of an ambulance's siren when it moves away from a stationary hearer?
Answer:
A) As the ambulance's siren moves toward a stationary hearer, the quality of sound will have a higher pitch
B) As the ambulance's siren moves away from a stationary hearer, the quality of sound will have a lower pitch.
Explanation:
From Doppler effect, the closer the source of sound gets to the observer, the higher the frequency and in turn the higher the pitch.
Meanwhile, the farther a source goes from an observer, the lower the frequency of the sound and also the lower the pitch.
Thus, as the ambulance's siren moves toward a stationary hearer, the quality of sound will have a higher pitch.
As the ambulance's siren moves away from a stationary hearer, the quality of sound will have a lower pitch.
Answer:
a. The quality of the sound would have a high pitch and thus be loud.
b. The quality of the sound would have a low pitch and thus would have a lower volume than the sound from the source.
Explanation:
Using the formula for Doppler shift f' = (v ± v')f/(v ± v") where v = speed of sound in air, v'= speed of hearer = 0 m/s (since he is stationary), v" = speed of ambulance and f = frequency of sound from ambulance
So, f' = (v ± v')f/(v ± v")
f' = (v ± 0)f/(v ± v")
f' = vf/(v ± v")
a. What is the quality of the sound of an ambulance's siren when it moves toward a stationary hearer?
Since the source (ambulance) moves towards the detector, (hearer), we would get an upwards shift in frequency. (Since our denominator has to be a minimum, so we use the minus sign for v"). So, the quality of the sound would have a high pitch and thus be loud.
b. What is the quality of the sound of an ambulance's siren when it moves away from a stationary hearer?
Since the source (ambulance) moves away the detector, (hearer), we would get a downward shift in frequency. (Since our denominator has to be a maximum, so we use the plus sign for v"). So, the quality of the sound would have a low pitch and thus would have a lower volume than the sound from the source.
A tank containing water up to a depth of 650 mm is stationary. Find the force exerted by fluid of specific gravity 0.55 on the side of tank, width of tank is 1.5m. Ρ water = 1000 kg/m³:
Answer:
3415.91 N
Explanation:
We know pressure, P at depth, h is P = ρgh where ρ = density of fluid = specific gravity × density of water = 0.55 × 1000 kg/m³ = 550 kg/m³, g = acceleration due to gravity = 9.8 m/s² and h = depth of water = 650 mm = 0.650 m
So, P = ρgh
= 550 kg/m³ × 9.8 m/s² × 0.650 m
= 3503.5 N/m²
Now pressure P = F/A where F = force on the side of tank and A = area of side of tank = depth of water × width of tank = 0.650 m × 1.5 m = 0.975 m²
So, F = PA
= 3503.5 N/m² × 0.975 m²
= 3415.913 N
≅ 3415.91 N
When ___ attacks the surface of a metal, it becomes tarnished.
Answer:corrosion (i believe)
Explanation:
Answer
Mix baking soda and salt with hot water and cover everything with it. The proportions are not crucial, but about 1 tablespoon of salt and 1 tablespoon of baking soda to 3 dl water should do the trick. Lightly tarnished objects should clean up in a few minutes, and you just rinse them of and dry them.
Explanation: