Resistors & Notations In Series In Parallel
A, B A + B A | B
A, B, C, D A+B+C+D A | B | C | D
In Combination Example A | B | ( C + D ) A | B | ( C + D )
Dec 1 2020
What is a mutual attraction between the nuclei and electrons in two different atoms called?
Superman stops a "speeding locomotive" of mass 8.0x103 kg in 4.0 seconds. If the train was originally moving at 40.m/s,
a) what is the change in momentum?
b.) What is the magnitude of the force which Superman exerts on the train?
Hello!
a) What is the change in momentum?
The change of the momentum is the velocity, because the velocity is reduced to zero.
We can calculate the aceleration, applicating the formula:
[tex]\boxed{a=\frac{V-Vi}{t} }[/tex]
Like you see, the final velocity will be zero, so:
[tex]a = \dfrac{0m/s-40m/s}{4s}[/tex]
[tex]a = \dfrac{-40m/s}{4s}[/tex]
[tex]a = -10\ m/s^{2}[/tex]
Like you see, the aceleration applicate by superman is of -10 m/s^2.
If the aceleration is negattive, means the velocity will decrease.
b.) What is the magnitud of the force wich superman exerts on the train?
For calculate the force applicate for superman, lets applicate the second law of Newton:
[tex]\boxed{F=ma}[/tex]
Lets replace and resolve it:
F = 8x10^3 kg * (-10 m/s^2)
F = 8000 kg * (-10 m/s^2)
F = -80 000 N
The force applicated is of -80000 Newtons.
When the force is negative means the force applicated in the another direction of the object what is traveling.
The input work done on a machine is 9.63 × 103 joules, and the output work is 3.0 × 103 joules. What is the percentage efficiency of the machine?
Answer:
31.15%
Explanation:
The formula used was
((Work output)/(Work input))×100
Answer:
C. 31.1 percent
Use this table of a school bus during morning pickups to answer the question.
What is the average speed of the bus between 2.8 km and 4.2 km?
Answer:
3.5
Explanation:
The answer should be 3.5
Answer:
3.5
Explanation:
On an ice skating rink, a girl of mass 50 kg stands stationary, face to face with a boy of mass 80 kg. The children push off of one another, and the boy moves away with a velocity of +3 m/s.
What is the final velocity of the girl?
–1.9 m/s
+1.9 m/s
–4.8 m/s
+4.8 m/s
Answer:
Pretty sure its -4.8%
Explanation:
Others asked this question and got this as an answer.
Answer:
C. –4.8 m/s
Explanation:
I just took the exam.
Why does the Moon seem to change shape?
A.
As the Moon revolves
around Earth, different parts are lit by the Sun.
B.
The viewpoint from Earth of the illuminated side of the Moon changes.
C.
Earth's shadow is blocking light from the Sun.
D.
The way the Moon produces light changes, so we see different shapes.
Answer:
A
Explanation:
I dropped a wet bar of soap on the ground is the bar of soap dirty or is the floor clean???
Answer:
the floor is clean and the soap is dirty. lol
I need the answer now
Answer:
It's C) color
Explanation:
--------
Andrew walks through his garden and observes that the shapes of dewdrops are not always the same. Suppose he wants to investigate using the scientific method. Which questions are testable questions that he can ask to look into the reasons for the different shapes?
A) Does the shape of the dewdrop depend on the temperature of the surface?
B) Which dewdrop seems to have the most unusual shape?
C) Is the material of the surface responsible for the shape of the dewdrop?
D) Which shape of dewdrop is the most pleasing to the observer?
E) Does the shape of the dewdrop depend on the moisture in the atmosphere?
Answer:
1
Explanation:
A uniform marble rolls down a symmetric bowl, starting from rest at the top of the left side. The top of each side is a distance h above the bottom of the bowl. The left half of the bowl is rough enough to cause the marble to roll without slipping, but the right half has no friction because it is coated with oil.
Answer:
[tex]h' = \dfrac{5}{7}h[/tex]
Explanation:
To find how far will the smooth side will the marble go in the upper direction, measured vertically from the bottom (leave your answer in terms of h)?
From the given information:
The potential energy for the marble starting at rest is:
PE = m*g*h
In the bottom of the bowl; the marble exhibit a linear and rotational K.E
[tex]K.E_{total} = K.E _{linear} + K.E _{rot}[/tex]
[tex]K.E_{total} = \dfrac{1}{2}mv^2+I\omega^2[/tex]
[tex]K.E_{total} = \dfrac{1}{2}mv^2+ \dfrac{1}{2}( \dfrac{2}{5}mR^2) ( \dfrac{v}{R})^2[/tex]
[tex]K.E_{total} = \dfrac{1}{2}mv^2+ \dfrac{1}{5}mv^2[/tex]
[tex]K.E_{total} = (\dfrac{5+2}{10})mv^2[/tex]
[tex]K.E_{total} = \dfrac{7}{10}mv^2[/tex]
By applying Conservation of energy, The Total Energy occurring in the marble when it started at rest is the same as the total energy when it gets to the midpoint in the bowl.
i.e.
[tex]P.E = K.E_{total}[/tex]
[tex]mgh = \dfrac{7}{10 }mv^2[/tex]
10 × mgh= 7mv²
making v² the subject of the formula, we get:
[tex]v^2 = \dfrac{10}{7 }gh[/tex]
Let us remember that the rotational K.E occurring at the midpoint of the bowl is still unchanged at the time the marble is moving to the left side.
Thus, by applying the Conservation of energy balance:
The linear K.E at the midpoint = The P.E of the marble
∴
[tex]\dfrac{1}{2}mv^2 = mgh'[/tex]
Making h' the subject, we get:
mv² = 2mgh'
Divide both sides by m
v² = 2gh'
Recall that [tex]v^2 = \dfrac{10}{7 }gh[/tex]
[tex]\dfrac{10}{7} gh = 2gh'[/tex]
10 gh = 14 gh'
Divide both sides by 2g
5h = 7h'
[tex]h' = \dfrac{5}{7}h[/tex]
The food web for a particular ecosystem is shown below.
What would most likely happen if the algae were removed from this ecosystem?
A.
The amount of sunlight would decrease.
B.
The ant population would increase.
C.
The tadpole population would decrease.
D.
The snake population would increase.
Answer:
D
Explanation:
Answer:
The tadpole population would decrease.
Explanation:
A food web shows how organisms produce and depend upon each other for food. In an ecosystem, when the population of one organism changes, it can affect the population(s) of other organisms.
In this food web, tadpoles depend upon algae as a food source. If algae were removed from the ecosystem, then the population of tadpoles would likely decrease due to a lack of available food.
Complete the passage.
Sound waves and some earthquake waves are
waves. Ocean, light, and other earthquake waves are
waves.
Answer:
Answer: Sound waves and some earthquake waves are longitudinal waves. Ocean, light and other earthquake waves are transverse waves.
Explanation:
There are 2 types of waves:
1. Longitudinal waves: These waves are defined as the waves in which the particles of the medium move in the direction of the wave. This requires a medium to travel. For Example: Sound Waves.
2. Transverse wave: These waves are defined as the waves in which the particles of the medium travel perpendicularly to the direction of the wave. This does not require a medium to travel. These can travel in vacuum also. For Example: Light waves.
Hence, Sound waves and some earthquake waves are longitudinal waves. Ocean, light and other earthquake waves are transverse waves
Answer:
Longitudinal, transverse.
Explanation:
The definitions:
Longitudinal wave: A type of wave that transfers energy parallel to the direction of wave motion.
Transverse wave: A type of wave that transfers energy perpendicular to the direction of wave motion.
Also:
If a dog ran at 5m/s,how far would it run in 45 s?
Answer:
225 meters
Explanation:
45*5 or 225 meters.
Hope this helps plz hit the crown :D
A bus approaches red traffic light, and slows down from a speed of 15
m/s to rest in 3 seconds. What is the average acceleration (in m/s)?
Answer:
-5
Explanation:
-15/3
A plane travels at a constant speed of 250 m/s as it flies once around a horizontal circle whose radius is 2542m.
a) how long does it take to fly around the circle one ?
b) If the speed were to double, what would happen to the acceleration that the plane experiences ?
c) What is the current value of the acceleration that the plane experiences?
d) if possible, find the net force acting on the plane during this turn. If it’s not possible, what information are we missing?
Volleyball was invented in 1905.
Answer:
REALLY??
Explanation:
Volleyball was invented in 1905.
When two objects collide, they experience the exact same amount of force in opposite directions.
O True
O False
Answer:
True
Explanation:
In a collision between two objects, both objects experience forces that are equal in magnitude and opposite in direction. Such forces often cause one object to speed up (gain momentum) and the other object to slow down (lose momentum).
forces acting on a ball as it is being squeezed
Justin strikes a 0.058-kg golf ball with a force of 260 N. If the ball moves with a velocity of 63 m/s, calculate the time the ball is in contact with the club
Answer:
0.014s
Explanation:
Given parameters:
Mass of the ball = 0.058kg
Force = 260N
Velocity of the ball = 63m/s
Unknown:
Time of contact = ?
Solution:
To solve this problem, we apply Newton's second law of motion which is mathematically expressed as;
Ft = m(v - u)
F is the force
t is time
m is the mass
v is the final velocity
u is the initial velocity = 0m/s
Insert the parameters and find t;
260 x t = 0.058(63 - 0)
260t = 3.65
t = 0.014s
Przyjrzyj się ilustracji, a następnie wykonaj polecenia.
2) Dopasuj do każdej cyfry rzymskiej nazwę substancjí z ramki poniže
. • lod
• szkło
V
• plastik
dwutlenek węgla
• woda
Answer:
what is this???
I don't know these kind of language exist...
when measuring the potential difference across a component, you need
Answer:
Measuring potential difference Potential difference is measured using a device called a . Just like ammeters, some types have a pointer on a dial, but most have a digital display. However, unlike an ammeter, you must connect the voltmeter in parallel to measure the potential difference across a component in a circuit.
Q4. Cheetahs have a top speed of 120 km/h and can accelerate at a constant rate of 9.5 m/s2. How long would it take a cheetah, stalking its prey at 4.2 m/s, to reach its top speed?
What is .00245 in scientific notation?
Answer:
2.45 x 10^-2
Explanation:
All numbers in scientific notation or standard form are written in the form
m × 10n, where m is a number between 1 and 10 ( 1 ≤ |m| < 10 ) and the exponent n is a positive or negative integer.
To convert 0.0245 into scientific notation, follow these steps:
Step 1) Move the decimal 2 times to right in the number so that the resulting number, m = 2.45, is greater than or equal to 1 but less than 10
Step 2) Since we moved the decimal to the right the exponent n is negative
n = -2
Step 3) Write in the scientific notation form m × 10n
= 2.45 × 10-2
Therefore,
2.45 × 10-2 is the scientific notation form of 0.0245 number and 2.45e-2 is the scientific e-notation form for 0.0245
Here are some examples of decimal to scientific notation calculator
How do you find the average speed of three speeds?
Answer:
Assess what information you are given. Use this method if you know:
the total distance covered by one person or vehicle; and
the total time it took that person or vehicle to cover the distance.
Explanation:
Hope this helps! I might be wrong, so tell me if I am
Answer:
Average speed can be calculated by dividing the total distance the object travels by the total amount of time it takes to travel that distance.
Explanation:
This is as much as I can help you, i don't know much else on how to do that ;w; sorry
What is the mass of a bird if it has a potential energy of 147J when flying at a height of 30 m above the ground?
Answer:
0.5kg
Explanation:
Given parameters:
Potential energy = 147J
Height = 30m
Unknown:
Mass of the bird = ?
Solution:
Potential energy is the energy due to the position of a body. Now, the expression for finding the potential energy is given as;
P.E = mgH
m is the mass
g is the acceleration due to gravity = 9.8m/s²
H is the height
147 = m x 9.8 x 30
m = 0.5kg
plssssssssssssssssssssssss help
Answer:
I think it's b
Explanation:
........
Please help with this! The selected answer is the incorrect one, I'm making corrections.
Answer:
The answer is C-Spin a magnet around the wire on the piece of iron. Hope that helps :)
What weighs more 500 pounds of bricks or 500 pounds of feathers.
Answer:
It's the same........
Answer:
They both the same weight
Can someone help me or find the answers to this chart please?
Explanation:
this is too though bro do it by ur self
Study the arrow that is circled in the image.
What happens at this point?
Warm air is rising.
Cool air is sinking.
There is a difference in air pressure.
Cool air is less dense than warm air.
Answer:
There is a difference in air pressure.
Explanation:
I hope this helps you, BTW I got this right when I did the test
The given point is the separation between hot and cold current as a result of difference in air pressure.
What is a convection current?A convection current is a type of heat transfer that occurs from the movement of hot air and cold air due to difference in air pressure.
Upward arrowThe upward arrow shows hot air rising up due to its low density.
Downward arrowThe downward arrow shows cold moving downwards to replace the risen hot air due to its high density.
Thus, the difference in air pressure between the hot air and cold air is causes convection current.
Learn more about convection current here: https://brainly.com/question/20295382