Answer:
A
Explanation:
Answer:
C
Explanation:
Light travels in straight lines
Shadows are evidence of light travelling in straight lines. An object blocks light so that it can't reach the surface where we see the shadow.
Use the "Law of Reflection" to describe why you cannot see your reflection in a piece
of paper.
Answer:
it does not mirror the image
An electromagnet is a device that uses an electric current to produce a magnetic field.
Electromagnets are typically composed of a piece of metal wrapped with wire and connected to a battery. The battery provides the electric current, and the loops or coils of wire enhance the magnetic field. The more loops there are, the stronger the magnetic field.
When electric current flows through the electromagnet, the metal core becomes magnetized, so it possesses a north pole and a south pole.
Motors place electromagnets inside of permanent magnets as shown below.
However, motors are designed so that the polarity of the electromagnet constantly flips. That is, the north pole becomes the south pole, and the south pole becomes the north pole, every time the electromagnet turns 180 degrees.
Why is it designed this way?
A.
to conserve the energy in the battery
B.
to constantly polarize the field magnet
C.
so the electromagnet will continuously turn
D.
so the magnetic field will get stronger
The reason why motors are designed so that the polarity of the electromagnet constantly flips.is
C. so the electromagnet will continuously turn
Why is motor designed that wayThe reason motors are designed so that the polarity of the electromagnet constantly flips is to continuously turn the electromagnet. This allows the motor to rotate continuously, rather than becoming stuck in one position.
The flipping of the polarity causes the electromagnet to attract and repel from the permanent magnets, creating a rotating motion.
Therefore, the correct answer is C.
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Sally performed an experiment.The measurement was taken three times.
68.152 ml 68:154 ml 68.160 ml
The correct measurement was 68.2 ml. Is Sally's measurement accurate, precise,or
neither?
A. accurate
B. precise
C. both
D. neither accurate nor precise
Please answer correctly!!.....
Answer:
accurate it means trying to find accurate or exact value. or tends to find exact value,
Explanation:
If it takes 726 watts of power to move an object 36 m in 14 s, what is the mass of the object?
Answer:
Explanation:
Given
Power (p)= 726 watt
Time (t) = 14 sec
distance travelled (d; h) = 36 m
mass (m) = ?
we know
Power (p) = W/t ( w = work done )
p = m * g * h / t ( w = m * g* h)
726 = m * 10 * 36 / 14 ( g = 10 m/s^2)
m = 28. 23 kg
or if we use the value of g as 9.8 m/s^2
the mass will be
= 28.8 kg
hope it helps :)
The mass of the object if it takes 726 watts of power to move an object 36 m in 14 s is 28.8 kg.
What is mass?An object's inertia, a fundamental property, is measured by its mass, a fundamental indicator of the volume of substance inside the thing. Definitions of mass can seem circular since it is such a fundamental quantity and is challenging to define in terms of another.
It is possible to define every mechanical quantity in terms of mass, length, and time. The SI unit for mass, denoted by the letter m, is the kilogram. While mass is typically thought of as an immutable feature of an item, relativistic mass must be taken into account when traveling at speeds close to the speed of light.
Given:
The Power, p = 726 watt
The Time, t = 14 sec
distance travelled, d = 36 m
Calculate the power by the given formula
p = W / t
p = m * g * h / t ( w = m * g* h)
726 = m * 9.8 * 36 / 14 ( g = 10 m/s^2)
m = 28. 8 kg
Therefore, the mass of the object If it takes 726 watts of power to move an object 36 m in 14 s is 28.8 kg.
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What is a wave's speed if it has a wavelength of 3.2x10^-7 m and a period of 2.8x10^-12s
Answer: 1.1·10^5 m/s
Explanation: speed = wavelength · frequency v = λf and
frequency f = 1/T , in which T = period
Speed v= λ/T = 3.2·10^-7 m /2.8·10^-12 s = 114285,7 m/s
define the artificial silk?
Answer:
Artificial silk or art silk is any synthetic fiber which resembles silk, but typically costs less to produce.
Explanation:
Answer:
Artificial silk or art silk is any synthetic fiber which resembles silk, but typically costs less to produce. Frequently, "artificial silk" is just a synonym for rayon. When made out of bamboo viscose it is also sometimes called bamboo silk.
A wave is travelling at 3000 m/s has a wavelength of 1 m.
a) Calculate the frequency of the wave.
b) Calculate the time period of the wave.
c) How many complete wave cycles will occur in:
i. 1 second
ii. 10 senconds
iii. 1 minute
Answer:
a] 3000hz
b]3.33 × 10⁻⁴
ci]300
ii] 3000
iii]60,000
Explanation:
If a wave is travelling at 3000 m/s and has a wavelength of 1 meter the frequency of the wave would be 3000 Hz and the time period of the wave would be 3.33×10⁻⁴ seconds.
What is the frequency?It can be defined as the number of cycles completed per second. It is represented in hertz and inversely proportional to the wavelength.
Frequency = 1/T
As given in the problem If a wave is travelling at 3000 m/s and has a wavelength of 1 meter,
The frequency of the wave would be 3000 Hz.
The time period of the wave would be 3.33×10⁻⁴ seconds.
There would be 3000 complete wave cycles in 1 second, 300 wave cycles in 10 seconds, and 50 wave cycles in 1 minute.
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Use the drop-down menus to complete the sentences.
A thin wire has
resistance than a thick wire.
A short wire has
resistance than a long wire.
A warm wire has
resistance than a cool wire.
Answer:
A thin wire has more resistance than a thick wire
A short wire has less resistance than a long wire
A warm wire has more resistance than a cool wire
Answer: More, less, more
Explanation:
Edge 2021
describe how you would determine the half-life of a substance from an activity/time graph, plsplspls help
Answer: At any time, the number of decays per reasonable
time unit is proportional to the amount of the isotope present. (This is expressed by the first-order rate equation for a one-decay process.) Therefore, it does not matter whether one looks at the amount or the number of decays. It may be easier to measure the number of decays by e.g. a Geiger counter and prefer it for that reason.
It now matters what you understand to be the rate: the number of decays per second or the percentage of nuclei decaying at any given time. The first becomes less over time, the second one is a constant for each isotope.
You must have a reasonable number of decays within your time unit. If the half-life is long, it makes little sense to look at millisecond slices.
The frequency of a wave is 2 Hz and the wavelength is 4 m. What is the wave speed?
Answer:
4/2=2m/s
Explanation:
A body is moving with a velocity of 15m/s . If the motion is uniform. How much distance will be the velocity after 10s
Answer:
Distance = 150 meters.
Explanation:
Given the following data;
Velocity = 15 m/s
Time = 10 seconds
To find the distance;
Velocity can be defined as the rate of change in displacement (distance) with time. Velocity is a vector quantity and as such it has both magnitude and direction.
Mathematically, velocity is given by the equation;
[tex]Velocity = \frac{distance}{time}[/tex]
Making distance the subject of formula, we have;
[tex] Distance = velocity * time [/tex]
[tex] Distance = 15 * 10 [/tex]
Distance = 150 meters
Aluminium + hydrochloric acid =
Answer:
Aluminum hydrochloric acid
Explanation:
Aluminum reacts with diluted hydrochloric acid at room temperature. The metal aluminium dissolves in hydrochloric acid, producing aluminum chloride and colorless hydrogen gas. The reaction taking place between aluminium and hydrochloric acid is irreversible. And the final products will not react with each other.
¿Qué pasa en nuestro cerebro cuando tomamos decisiones? Ejemplo: Estoy tocando una plancha caliente, y saco la mano rápidamente, ¿que paso en mi cerebro?
Answer:
Debido a la información de las neuronas sensoriales al cerebro.
Explicación:
Cuando toco una plancha caliente, extiendo la mano rápidamente porque las neuronas sensoriales presentes en la piel de nuestro cuerpo envían señales al sistema nervioso central, es decir, al cerebro. El cerebro toma decisiones de acuerdo con los estímulos y envía instrucciones a través de las neuronas motoras a los músculos para retirar las manos del hierro caliente a fin de evitar efectos nocivos en la piel debido al calor. El lóbulo frontal es una parte del cerebro que controla la personalidad, la toma de decisiones y el razonamiento.
Answer if you actually have the answer unlike Miss Madhumitaa!!!!
A 20.0 cm tall object is placed 50.0 cm in front of a convex mirror with a radius of curvature of 34.0 cm. Where will the image be located, and how tall will it be? Please show all work. Use the steps below
Step 1: Find the focal length, step 2: find the image distance using the mirror equation step 3: Use the magnification relationship to find the image height.
Explanation:
Hey Why you wrote my name hn?
A pump is to lift 20.0 kg of water per minute through a height of 25.50 m. What output rating should the pump motor have?
Answer:
the output rating that should the pump motor have is 83.30 Watt
Explanation:
Given that
The pump lift 20 kg of water per minute having a height of 25.50 m
We need to find out the output rating that should the pump motor have
As we know that
power = energy ÷ time
= m g h ÷ t
= 20.0 × 9.8 × 25.50 ÷ 60
= 83.30 Watts
Hence, the output rating that should the pump motor have is 83.30 Watt
The periodic wave in the diagram below has a frequency of 80. hertz.
What is the speed of the wave? (1) 13 m/s (2) 60. m/s (3) 27 m/s (4) 120 m/s
Answer:
hi how are you
2) 5/8
4) 5/8
According to Newton’s second law, the mass of an object is 120kg and it is accelerating at a rate of 5m/s2 . The object’s force would be
Answer:
F = 600 N
Explanation:
The second law is F = m * a
The mass (m) is in kg = 120
The acceleration in in m/s^2 = 5
The force is in Newtons.
m and a do not require any conversions. They are in the correct units.
F = 120 * 5
F = 600 N
How can the power of an object required to lift a mass up a height be increased ?
A .reduce the height
B .reduce the mass
C .increase the time
D .reduce the time
The amswer should be B. reduce the mass
A base is a substance that forms hydroxide ions in a water solution.
O A. True
O B. False
Explanation:
A. True , a base is a substance that forms hydroxide ions in water
hope it helps
Which three elements have the most similar chemical properties?
A. O, N, Si
B. K, Rb, Cs
C. Ar, Kr, Br
D. B, C, N
The people who write computer programs
Answer:
Someone who writes software or programs for computers is called a programmer.
Explanation:
A 22 g block of ice is cooled to −70 ◦C. It is added to 589 g of water in an 83 g copper calorimeter at a temperature of 21◦C. Find the final temperature. The specific heat of copper is 387 J/kg · ◦C and of ice is 2090 J/kg ·◦C . The latent heat of fusion of water is 3.33 × 105 J/kg and its specific heat is 4186 J/kg · ◦C . Answer in units of ◦C
When bitten by an animal, one should:
Keep the animal under observation for 14 days
Stay under observation for a doctor for 14 days
Wait for symptoms to develop
Consider rabies injections if the animal is not found
Please hurry!
Answer:
consider rabies injections if the animal is not found
hope it helps
Answer:
I think flush it out with soap and water for a while but for first aid Consider rabies injections
Explanation:
The metric unit that is most often used to describe weight is the _________
Answer:
mass
Explanation:
mass is used in measuring weight. for example kg, tonnes
Scavengers are organisms that help clean a habitat by feeding on dead or rotting flesh. They help break down the remains left behind by carnivores. Vultures and maggots (baby flies) are common scavengers.
Decomposers are organisms that break down the remains of dead animals or plants. Many live in or on the soil. Fungi and bacteria are examples of decomposers.
Which of the following is an example of decomposers at work?
a. a fish eating dead seaweed floating in the water
b. a vulture picking apart a dead mouse in the woods
c. a squirrel gnawing at a dead bird on the ground
d. a fungus growing on a rotten tomato, breaking down its skin
Answer:
I think no B
if wrong correct me pls
have a nice day
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Answer: B
Explanation:
Vultures and maggots (baby flies) are common scavengers. Decomposers are organisms that break down the remains of dead animals or plants. ... Green plants are called producers because they take energy from sunlight and produce food in which the energy is stored.
ASAP!!!
What is the purpose of a heavy stream appliance?
provides breathable air from attached air tanks
focuses the fluid flow into a heavier stream
moves or removes smoke and gases from buildings and passageways
removes citizens from burning or hazardous structures
Answer:
B is the answer.
Explanation:
I am doing the same Assignment.
A high-temperature gas is compared to the same gas at lower temperature. Which of the following statements is true?
A. Every molecule in the high-temperature gas is moving faster than every molecule in the low-temperature gas.
B. The average molecular speed in the high-temperature gas is faster than the average molecular speed in the low-
temperature gas.
C. Both A and B are true.
D. Neither A nor B is true.
Answer:
I think it is C
Explanation:
If the temperature of a gas increases, the gas particles have a higher average speed as they gain kinetic energy. They collide more frequently with the walls of the container, which produces a bigger pressure.
A 20.0 Ohm and 60.0 Ohm resistor
are connected in series to a 9.00 V
battery. What is their equivalent
resistance?
(Unit = Ohms)
Answer:
for resistors in series, add the resistances to get their equivalence. The answer is
80.0 Ohms
List out of how animals and plants can cause weathering.
Plants
Seasons change because: A. Earth is titled on its axis as it revolves around the Sun B. Earth rotates on its axis. C. The amount of energy from the Sun changes. D. Earth's distance from the Sun changes.
Answer:
Its A
Explanation: