A graduated plank of length 90cm sits on a knife edge at 40cm mark. When a load of 50g is placed at 20cm, find the mass that will balance the plank at 70cm length.
Answers
Answer:
33.3 g ≈ 33 g
Explanation:
Please see attached photo for explanation.
From the attached photo, M is the mass that we must obtain to balance the plank.
The mass, M can be obtained as follow:
Anticlockwise moment = clockwise moment
Anticlockwise moment = 50 x 20
Clockwise moment = M x 30
Anticlockwise moment = clockwise moment
50 x 20 = M x 30
Divide both side by 30
M = (50 x 20)/30
M = 33.3 g ≈ 33 g
Therefore, the mass that will balanced the plank at the 70 cm length is appropriately 33 g
Related Questions
Write a report on the lap experiment: Motion with Constant Acceleration
Answers
Answer:
Purpose: To observe how an object’s position and velocity change while it is moving with a constant acceleration.
Question: How does an object’s position and velocity change as the object accelerates?
Hypothesis: If the fan speed increases, then the acceleration of the cart increases, because a greater fan speed supplies more energy to move the cart.
Variables:
• Independent variable: fan speed
• Dependent variable: acceleration of the cart
• Controlled variables: mass
Materials:
• Cart with Fan (1 kg)
• CM ruler (1 cm)
• Stop watch (0.0 cm pe sec)
• Flag
Procedure:
1. Use the setup on “Force and Fan Carts” Gizmo.
2. First, put the fan speed on low and no friction surface.
3. Press the start button and record the final time when the cart crosses the finished line. Record on table B.
4. Then, click on the data tab to record the speed data, total distance, average velocity, and acceleration. Record on table A and B.
5. After, observe the position vs. time graph with the speed and line graph toggled. Record on table C.
6. Repeat steps 2-5 on fan speed on medium and high with no friction surface.
7. Next, reset and put fan speed on low.
8. Press start and pause on 4 seconds.
9. On the same trial turn off the fan speed and hit start again.
10. Observe the graph and write observations on table D.
Analysis and Conclusion:
In conclusion, my hypothesis matches the data, because the data shows that increasing the fan speed increases the acceleration of the cart. The trends for all fan speeds are linear slope for speed. The higher the fan speed, the less time it took for the cart to cross the finish line.
Data:
Explanation:
Sorry can’t copy and paste results
Answer:
for that pervious answer why cant we copy and paste?
Explanation:
At summer camp, the swimming course runs the length (L) of a small lake. To determine the length of the course, the camp counselors measure the two "dry" legs of a right triangle. What is the length in meters of the swimming course in the figure below?
Answers
Answer:
47 m
Explanation:
Data obtained from the question include the following:
Length of dry leg 1 (L1) = 40 m
Length of dry leg 2 (L2) = 25 m
Length of swimming course (L) =..?
The length of the swimming course can be obtained by using pythagoras theory as shown below:
L² = L1² + L2²
L² = 40² + 25²
L² = 1600 + 625
L² = 2225
Take the square root of both side.
L = √2225
L = 47.1 ≈ 47 m
Therefore, the length of the swimming course is approximately 47 m.
Changes in which property are heard when the Doppler effect occurs? pitch amplitude volume wavelength
Answers
Changes in pitch are heard when the Doppler effect occurs.
What is the Doppler effect?The Doppler effect, also known as the Doppler shift, is a term used to explain changes in frequency caused by moving sources of sound or light with regard to an observer.
The Doppler effect is the apparent change in frequency or wavelength of a wave that is perceived by an observer when the source of the wave or the observer is moving relative to each other.
In the case of sound waves, if the source of the sound is moving towards the observer, the frequency of the sound waves is perceived to be higher, resulting in a higher-pitched sound.
Conversely, if the source of the sound is moving away from the observer, the frequency of the sound waves is perceived to be lower, resulting in a lower-pitched sound.
This effect can be observed in many everyday situations, such as the changing pitch of a siren as an ambulance or police car passes by.
Learn more about doppler's effect here:
https://brainly.com/question/15318474
#SPJ6
Answer:
option A) pitch
Explanation:
2023 :)
PLZ ANSWER ASAP, I WILL MARK AS BRAINLIEST
Answers
Answer:
electric potential energy=
[tex]\frac{KQq}{r} [/tex]
so the electric potential energy and distance(r) are inversely proportional.
then, the greatest energy occur in the smallest distance b/n the two balloon.
Answer:
Top Left
Explanation:
The two balloons would create enough friction and energy to separate from each other as two balls of air would push each other from their energy
A boy on a chairlift moving parallel to the mountain slope at a speed of +15 m/s watches a skier going straight down the mountain with a speed of -35 m/s. What is the velocity of the skier relative to the chairlift? A. -50 m/s B. -35 m/s C. -20 m/s D. +15 m/s E. +50 m/s
Answers
Answer:
A. -50 m/s
Explanation:
Given
Velocity of Chairlift = +15m/s
Velocity of Skier = -35m/s
Required
Determine the velocity of the skier relative to the chairlift
Basically, relative velocity is the difference between the two velocities;
Having said that;
Relative velocity of the skier relative to the chairlift = Velocity of the Skier - Velocity of the Chairlift
Relative velocity of the skier relative to the chairlift = -35m/s - (+15m/s)
Open bracket
Relative velocity of the skier relative to the chairlift = -35m/s - 15m/s
Relative velocity of the skier relative to the chairlift = -50
Help me please, ;) I could use it
Answers
Answer:
The solution(s) are in order with respect to the attachments
[tex]2.613\:\cdot10^5[/tex] Joules ; 5. Adding the same amount of heat to two different objects will produce the same increase in temperature ; 2. Same speed in both ; 2. A
Explanation:
Diagram 1 ( Liquid Nitrogen ) : So as you can see, we want our units in Joules here, and can therefore multiply the mass of gaseous nitrogen and the latent heat of liquid nitrogen, to cancel the units kg, and receive our solution - in terms of Joules. Let's do it.
q ( energy removed ) = mass of nitrogen [tex]*[/tex] latent heat of liquid nitrogen,
q = 1.3 kg [tex]*[/tex] 2.01 [tex]*[/tex] 10⁵ J / kg = [tex]1.3\:\cdot \:2.01\:\cdot \:\:10^5[/tex] = [tex]10^5\cdot \:2.613[/tex] = [tex]100000\cdot \:2.613[/tex] = [tex]261300[/tex] Joules = [tex]261.3[/tex] kiloJoules = 2.613 [tex]*[/tex] 10⁵Joules is the energy that must be removed
Diagram 2 : The same amount of heat does not necessarily mean the same increase in temperature for two different objects. The increase in temperature depends on the specific heat capacity of the substance. Therefore your solution is 5 ) Adding the same amount of heat to two different objects will produce the same increase in temperature.
Diagram 3 : The temperatures in both glasses are the same, and hence the molecules have the same average speed. Therefore your solution is 2 ) Same speed in both.
Diagram 4 : Glass A has more water molecules, and hence has more thermal energy. Your solution is 2 ) A.
You are in a desert on a hot day and see water in the distance. It is not really there, you see it because light bends due to a difference in the temperature of air. Which behavior of light best explains this? Select one: a. reflection b. translocation c. diffraction d. refraction
Answers
Answer:
d) refraction
Explanation:
in physics, refraction is the change of direction of a wave passing from one medium to another. refraction of light is the most commonly observed phenomenon but other waves such as sound waves and water waves also experience refraction
Answer:
B. Translocation
Explanation:
It means a change in location. It often refers to genetics, when part of a chromosome is transferred to another chromosome, you want a change in location because you are so thirsty in the desert and need water
Nia has $19.50 to ride the subway around New York. It will cost her $0.75 every time she rides. Identify the dependent variable and independent variable in this scenario.
A The number of rides and the total cost are both independent variables.
B The number of rides and the total cost are both dependent variables.
C The number of rides is the independent variable, and the total cost is the dependent variable.
D The total cost is the independent variable, and the number of rides is the dependent variable.
Answers
Answer:
C The number of rides is the independent variable, and the total cost is the dependent variable.
Explanation:
The total cost is the dependent variable, because it depends on the number of rides. The number of rides is the independent variable; it is the variable that Nia controls.
Label the parts of the brain. medulla oblongata thalamus cerebrum cerebellum brain stem pons hypothalamus midbrain
Answers
Answer:
Medulla oblongata is lower part of brain.
Cerebrum and cerebellum are the upper hemispheres of the brain.
Explanation:
Cerebrum is the largest part of the brain and is composed of right and left hemispheres.
Cerebellum is the part of brain that lies inside the cerebellum.
Medulla Oblongata is lowest part of brain stem which is most vital part of the brain.
Thalamus is a small region of the brain located above the brain stem. Its main function is to transmit sensory signals to cerebral cortex.
Brain stem act as relay center connecting the cerebrum and cerebellum to the spinal chord.
Hypothalamus is the mid brain located near the pituitary glands. It is very small region of the brain but it plays an important role in maintaining the body temperature and releasing the hormones.
Answer:
Medulla oblongata: The bottom part of the brainstem helps regulate your breathing, heart rhythms, blood pressure and swallowing.
Explanation:
Help me please, I need it
Answers
Answer:
3000 m/s
Explanation:
The kinetic energy is:
KE = 3/2 kT
where k is Boltzmann constant and T is absolute temperature.
Kinetic energy is also:
KE = 1/2 mv²
where m is the mass and v is the speed.
1/2 mv² = 3/2 kT
mv² = 3kT
v = √(3kT / m)
v = √(3 × 1.38×10⁻²³ J/K × (273 + 27) K / 1.38×10⁻²⁷ kg)
v = 3000 m/s
Plz help me with question 3
Answers
Answer:
C. 110 - 140
Explanation:
Answer:
i think the best answer is c
Help me pls I'm struggling
Answers
Answer:
2. The temperature doubles.
014) 48.6 J
015) 13,700 J
016) 5.94×10⁻²¹ J
Explanation:
PV = nRT
P and n are constant.
nR/P = k
V/T = k
If the volume doubles, the temperature also doubles.
014) The kinetic energy per atom is:
KE = 3/2 kT
KE = 3/2 (1.38×10⁻²³ J/K) (21 + 273) K
KE = 6.09×10⁻²¹ J
The total kinetic energy is:
KE = (6.09×10⁻²¹ J) (7.99×10²¹)
KE = 48.6 J
016) The kinetic energy per atom is:
KE = 3/2 kT
KE = 3/2 (1.38×10⁻²³ J/K) (14 + 273) K
KE = 5.94×10⁻²¹ J
015) The total kinetic energy is:
KE = (5.94×10⁻²¹ J) (3.82 mol) (6.02×10²³ atom/mol)
KE = 13,700 J
When do we use v=2s/t and what does that equation mean?
Answers
Answer:
This can be used to find out the speed of the returned journey. The equation means speed = returned distance ÷ time.
Explanation:
If the angle of incidence of a light source to a shiny surface is 30 degrees, what will the angle
of reflection be?
150 degrees
90 degrees
60 degrees
30 degrees
Answers
Angle of incidence always equals angle of reflection. Think of a tennis ball being hit into a wall. The ball will bounce off at the same angle that it approached with. The angles mentioned are formed through the line called the "normal", which is the line perpendicular to the surface.
*** HOPE THIS HELP YOU***
Plz Help me with this
Answers
Answer:
Cools ; size
Explanation:
The rate at which magma cools determines the size of the crystals in the new rock. Igneous rocks are formed from the cooling and solidification of molten magma which finds its way to the surface or depth of very low pressure beneath the surface. This place or depth of cooling of magma affects the cooling rate and hence the size of the crystals formed. Igneous rocks formed at depths below the surface have more time to cool and allows more time for Crystal growth and hence produce coarse grained crystal grains called Intrusive igneous rocks which have significantly larger crystals than those formed on the surface which cools rapidly and allowing very little time for crystal growth giving rise to the formation of fine grained crystals and are called extrusive igneous rocks.
conditions of equilibrium of parallel coplanar forces
Answers
Answer:
Bruh............
Explanation:
Levi observed properties of four different waves and recorded observations about each one in his chart. A 2-column table with 4 rows. The first column labeled Wave has entries W, X, Y, Z. The second column labeled Observations has entries travels fastest through metal, travels fastest through air, travels more slowly through water than air, travels more slowly at cool temperatures. Which statement is best supported by the table? Wave W and Y are light waves, Wave Z is a sound waves, and it is impossible to tell what kind of wave Wave X is. Wave W is a light wave, Waves X and Y are sound waves, and it is impossible to tell what kind of wave Wave Z is. Waves W and Z are sound waves, and Waves X and Y are light waves. Wave W is a sound wave, Waves X and Y are light waves, and it is impossible to tell what kind of wave Wave Z is.
Answers
Answer:
Wave W is a sound wave, Waves X and Y are light waves, and it is impossible to tell what kind of wave Wave Z is.
Explanation:
W travels fastest through metal
X travels fastest through air,
Y travels more slowly through water than air
Z travels more slowly at cool temperatures
W appears to be sound wave as sound travels fastest through metal .
X appears to be light wave as light travels fastest in air .
Y also appears to be light wave as speed of light is reduced when it passes from air to water .
Z It is impossible to tell anything about the nature of Z wave .
Answer:
d
Explanation:
help pls 30 points need help
Answers
Answer:
C
Explanation:
Answer:
I believe the answer is C.
Explanation:
Five equal negative charges are uniformly spaced in a semicircular
arc of radius ro with its center at the origin. The charges positions in
polar coordinates are given by (o. 6.), where the values of 0 are 0°,
45°, 90°. 135º. and 180°. At the position (x, y) = (ro, -ro) in the 4th
quadrant, which statement best describes the direction of the
resulting electric field?
The direction is that of a 3rd quadrant angle.
The direction is that of a 2nd quadrant angle.
The direction is that of a 1st quadrant angle.
The direction is that of a 4th quadrant angle.
Answers
Answer:
The direction is that of a 3rd quadrant angle
Explanation:
when you have 2 45 angles it equals to 90 then with the 90 we multiply by 2 due to the 2 adjacent angles equating to 180 which swings it to the 3rd quadrant angle
What is the missing number in the nuclear reaction shown below?
+
233
92
4
2
He +
?
90
Th
Answer here
SUBMIT
Answers
Answer:
[tex]\boxed{299}[/tex]
Explanation:
In this reaction, Sum of Atomic Masses of Left side = Sum of Atomic Masses of right side
Let the atomic mass of Thorium be x
So,
233 = 4 + x
Subtracting 4 to both sides
x = 233-4
x = 229
Which of the following is an accurate statement? A. Step-up voltage transformers have fewer turns in the primary that in the secondary winding. B. aC generators produce current that's pulsating but always remains positive C. Step-down voltage transformers have a different number of turns in the primary than in the secondary winding, so they change the incoming collage to a higher voltage D. DC generators produce current with a voltage that changes from positive to negative
Answers
Answer:
Option A is an accurate one.
Explanation:
A transformer being considered as a step-up transformer during which the performance (supplementary) voltage becomes stronger than that of the input (main) impedance of it. This kind of transformer reduces the electrical output to constantly keep the product input as well as power consumption equivalent.The other provided alternative is not related to the information provided there. So the response to the above seems to be the correct one.
1. If an object that stands 3 centimeters high is placed 12 centimeters in front of a plane
mirror, how far from the mirror is the image located? Explain your reasoning.
2. An object with a height of 0.3 meter is placed at a distance of 0.4 meter from a concave
spherical mirror. An image with a height of 0.1 meter is formed in front of the mirror.
How far from the mirror is the image located?
3. When an object with a height of 0.10 meter is placed at a distance of 0.20 meter from a
convex spherical mirror, the image will appear to be 0.06 meter behind the mirror.
What's the height of the image?
4. Compare and contrast the properties of the images formed by each mirror type in the
table.
Answers
Answer:
1. 12 cm
2. 0.133 m
3. 0.03 m
4. Plane mirror
Virtual image
Upright
Behind the mirror
The same size as the object
Concave mirror when the object is located a distance greater than the focal length from the mirror's surface
Real image
Inverted image
In front of the the mirror
Diminished when the object is beyond the center of curvature
Same size as object when the object is placed at the center of curvature
Enlarged when the object is placed between the center of curvature of the mirror and the focus of the mirror
Concave mirror when the object is located a distance less than the focal length from the mirror's surface
Virtual image
Upright image
Behind the the mirror
Enlarged
Convex mirror
Type = Virtual image
Appearance = Upright image
Placement = Behind the mirror
Size = Smaller than the object
Explanation:
1. For plane mirror, since there is no magnification, the virtual image distance from the mirror = object distance from the mirror = 12 cm behind the mirror
2. The height of the object = 0.3 m
The distance of the object from the mirror = 0.4 meters
Height of image formed = 0.1 meter
We have;
[tex]Magnification, \ m = \dfrac{Image \ height }{Object \ height } = \dfrac{Image \ distance \ from \ mirror }{Object\ distance \ from \ mirror }[/tex]
[tex]m = \dfrac{0.1}{0.3 } = \dfrac{Image \ distance \ from \ mirror }{0.4 }[/tex]
Image distance from the mirror = 0.1/0.3×0.4 = 2/15 = 0.133 m
Image distance from the mirror = 0.133 m
3. [tex]m = \dfrac{Image \ height}{0.10 } = \dfrac{0.06 }{0.20 }[/tex]
The image height = 0.06/0.2×0.1 = 3/100 = 0.03 meter
The image height = 0.03 meter
4. Plane mirror
Type = Virtual image
Appearance = Upright image with the left transformed to right
Placement = Behind the mirror
Size = The same size as the object
Concave mirror when the object is located a distance greater than the focal length from the mirror's surface
Type = Real image
Appearance = Inverted image
Placement = In front of the the mirror
Size = Diminished when the object is beyond the center of curvature
Same size as object when the object is placed at the center of curvature
Enlarged when the object is placed between the center of curvature of the mirror and the focus of the mirror
Concave mirror when the object is located a distance less than the focal length from the mirror's surface
Type = Virtual image
Appearance = Upright image
Placement = Behind the the mirror
Size = Enlarged
Convex mirror
Type = Virtual image
Appearance = Upright image
Placement = Behind the mirror
Size = Smaller than the object.
Answer:
1. The mirror is 12 centimeters away from the image. This is a plane mirror with a flat reflecting surface. The distance between the object and the mirror surface is equal to the distance between the mirror surface and the image.
2. hiho=siso
0.1 m0.3 m=si0.4 m
Multiply each side of this equation by 0.4.
0.4×(0.10.3=si0.4)×0.4
si=0.40.3
si = 0.133 m
3. hiho=siso
hi0.10 m=0.06 m0.02 m
Multiply each side of this equation by 0.10.
0.10×(hi0.10=0.060.20)×0.10
hi=0.0060.20
hi = 0.03 m
4.
Image Formation
Mirror Type Appearance Placement Size
Plane Virtual Erect (Upright); Appears to have left and right reversed Behind the mirror; the distance between the mirror and the image is equal to the distance between the mirror and the object Depends on the size of the mirror and placement of the object
Concave (when the object is located a distance greater than a focal length from mirror's surface) Real Inverted In front of the mirror Smaller than the object
Concave (when object is located a distance less than the focal length of the mirror) Virtual Erect (Upright) Behind the mirror Enlarged
Convex Virtual Erect (Upright) Behind the mirror Smaller than the object
Explanation:
PENN
Distinguish between resultant and equilibrant forces
Answers
Answer:
resultant is a single force that can replace the of a number of forces , equililbrant is a force that is exactly opposite to resultant
Explanation:
A study finds that there is a positive correlation between height and math test scores. The researcher concludes that taller people are better at math. However, another researcher points out that height is also correlated with age, and age is correlated with greater knowledge of math. What issue does this example represent?
Answers
Answer:
Spurious relationship
Explanation:
In statistics a spurious relationship is a correlated mathematical relationship of covariation between two variables or more which by themselves have no cause and effect relationship as a result of a coincidence or the existence of a third or confounding factor
The variables have covariation due to their correlation but they don't have a cause and effect relationship
An example of a spurious relationship is the increase in ice cream sales when there is an observed increase in the rate of drowning.
Help me please, please !
Answers
Answer:
b and d
a, c, e, and f
Explanation:
Ideal gas law:
PV = nRT
Solving for temperature:
T = PV / (nR)
Therefore, temperature is directly proportional to pressure and volume, and inversely proportional to the number of molecules.
T = k PV / N
Let's say that T₀ is the temperature when P = 100 kPa, V = 4 L, and N = 6×10²³.
a) T = k PV / N = T₀
b) T = k (2P) V / N = 2T₀
c) T = k (P/2) (2V) / N = T₀
d) T = k PV / (N/2) = 2T₀
e) T = k P (V/2) / (N/2) = T₀
f) T = k (P/2) V / (N/2) = T₀
b and d have the highest temperature,
a, c, e, and f have the lowest temperature.
What will be the pressure exerted by the object if 5000N of the force is acting on an area of 200 cm square
Answers
a ball is projected with a certain angle with initial velocity u. it covers horizontal range R. With what initial velocity it must be projected keeping the angle of projection same so its horizontal range becomes 2.25R
Answers
Answer:
1.5 u
Explanation:
The range equation is:
R = u² sin(2θ) / g
When u = v, R = 2.25 R.
2.25 R = v² sin(2θ) / g
2.25 u² sin(2θ) / g = v² sin(2θ) / g
2.25 u² = v²
1.5 u = v
Help me please, it's so hard
Answers
Answer:
4.58×10²³ atoms
5.94×10⁻²¹ J
1340 m/s
Explanation:
Use ideal gas law to find moles of gas.
PV = nRT
(1.266 atm × 101300 Pa/atm) (4/3 π (0.15 m)³) = n (8.31451 J/mol/K) (14 + 273) K
n = 0.760 mol
Use Avogadro's number to find number of atoms.
(0.760 mol) (6.02214×10²³ atom/mol) = 4.58×10²³ atoms
Average kinetic energy per molecule is:
KE = 3/2 kT
KE = 3/2 (1.38066×10⁻²³ J/K) (14 + 273) K
KE = 5.94×10⁻²¹ J
RMS speed of each atom is:
KE = 1/2 mv²
5.94×10⁻²¹ J/atom = 1/2 (0.004 kg/mol) (1 mol / 6.02214×10²³ atom) v²
v = 1340 m/s
A -0.00125 C charge is placed 3.62 m from a +0.00333 C charge. What is the magnitude of the electric force between them?
Remember, magnitudes are positive.
[?] N
Answers
Answer: 2858.7726N
Explanation:
Given that :
Charge 1 (q1) = -0.00125 C
Charge 2 (q2) = +0.00333 C
Distance (r) = 3.62 m
According to columb's Law: The magnitude of the force between any two charged objects :
Fe = (Kq1q2) / r^2
Coloumb's constant(k) = 9×10^9 Nm^2/C^2
Fe = (9×10^9 * 0.00125 * 0.00333) / 3.62^2
Fe = (0.0000374625 * 10^9) / 13.1044
Fe = 37462.5 / 13.1044
Fe = 2858.7726N
Answer:
2858.7726 N
Explanation:
acellus
* explain in your own words the phrase ,
'' a cell has a voltage of 1.5V''
plz help!!
Will give the brainliest!
plz answer correctly.
Answers
First of all, what is a cell?
A cell is a power source. It converts chemical energy into electrical energy which then allows a current to flow.
Then, what is a voltage?
A voltage is an electrical force required to push an electric current.
The answer to your question
The powers source requires a voltage of 1.5 to push the electrical current around the circuit