Answer:
I prefer online because I get social anxiety and I have seizures and ptsd episodes, so I'd just much rather be online
A scientist uses an electric motor to lift a load through a vertical distance of 2.0m.
He then increases the input power to the motor and repeats the experiment. The efficiency of the
motor does not change.
Which row correctly describes the effect that this has on the useful work done lifting the load and
the time taken to lift it?
work done
A
decreases
B
stays the same
decreases
time taken
decreases
decreases
stays the same
stays the same
с
D
stays the same
Answer: B
Explanation: efficiency is the useful energy supplied; useful energy supplied doesn't not change,
work done stays constant
in order to to increase the power of the motor, time would have to be decreased to get the wanted result..
When he increases the input power to the motor and repeats the experiment, work done stays the same but time taken decreases.
What is power?The quantity of energy moved or converted per unit of time is known as power in physics. The watt, or one joule per second, is the unit of power in the International System of Units. Power is also referred to as activity in ancient writings. A scalar quantity is power.
A motor's output power is calculated by multiplying its torque output by the angular velocity of its output shaft.
To lift a load through a vertical distance of 2.0m, in the both cases same amount of work-done happens because the displacement is same.
But as the input power, in second case, increases but the efficiency of the motor does not change, the time taken decreases ( as time taken = work done/power)
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When connected to a battery, a lightbulb glows brightly. If the battery is reversed and reconnected to the bulb, the bulb will glow:.
Explanation:
When a battery is connected to a lightbulb properly, current flows through the lightbulb and makes it glow.
what is force and energy
Answer:
(below)Explanation:
A force is any action that tends to alter the state of rest or uniform motion motion of a body. This is essentially Newton's first Law of motion. Energy is a property of a system that is a measure of the capacity to do work. for example Potential, kinetic
Hope this helps!
What is the difference between intrusive and extrusive rocks.
Answer:
Extrusive rocks form on the Earth's surface from lava, which is magma that has risen from underground. Intrusive rocks are formed when magma cools and solidifies within the planet's crust.
That's the difference
What is a major division between gravity and the electromagnetic force on one hand and the nuclear forces on the other?
1.Gravity and the electromagnetic force have infinite ranges while the nuclear forces have very small ranges.
2.Gravity and the electromagnetic force act on small objects while the nuclear forces act on large objects.
3.Gravity and the electromagnetic force act on large objects while the nuclear forces act on small objects
4.Gravity and the electromagnetic force have very small ranges while the nuclear forces have infinite ranges
Answer:
1) Gravity and the electromagnetic force have infinite ranges while the nuclear forces have very small ranges.
Explanation:
Gravity and the electromagnetic force have infinite ranges while the nuclear forces have very small ranges.
What is gravitational slingshot?In orbital mechanics and aerospace engineering, a gravitational slingshot is the use of the motion of a planet to alter the path and speed of an interplanetary spacecraft.
Given is to find the major division between -
Gravity and the electromagnetic force Gravity and nuclear forcesGravity and the electromagnetic force have infinite ranges while the nuclear forces have very small ranges.
Therefore, we can conclude that -
Gravity and the electromagnetic force have infinite ranges while the nuclear forces have very small ranges.
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1. Two boys A and B are asked to take 4 chairs from the ground floor to a room at the second floor. A takes 30 minutes to do this work while B takes 60 minutes for the same. (a) Name the physical quantity that is same for both boys. (b) Name the physical quantity that is different and find its ratio for the two boys.
Answer:
(a). Work done is the physical quantity which is same for both boys.
(b).Power is the physical quantity which is different for both boys.
The ratio of power of both boys is 2:1
Explanation:
Given that,
Time of boy A= 30 min
Time of boy B = 60 min
(a), We need to find the physical quantity that is same for both boys
Using given that,
We know that,
Work done depends on the force and displacement.
Here, force and displacement is same for both boys.
So, we can say that the work done will be same for both boys.
(b). We need to find the physical quantity that is different for both boys
Using given that,
We know that,
Power is equal to the work done divided by time.
Time is different for both boys so, the power will be different for both boys.
We need to calculate the ratio of power of both boys
Using formula of power
[tex]P=\dfrac{W}{t}[/tex]
Put the value into the formula
For boy A,
[tex]P_{A}=\dfrac{W_{A}}{t_{A}}[/tex]....(I)
For boy B,
[tex]P_{B}=\dfrac{W_{B}}{t_{B}}[/tex]....(II)
From equation (I) and (II)
[tex]\dfrac{P_{A}}{P_{B}}=\dfrac{\dfrac{W}{30}}{\dfrac{W}{60}}[/tex]
[tex]\dfrac{P_{A}}{P_{B}}=\dfrac{60}{30}[/tex]
[tex]\dfrac{P_{A}}{P_{B}}=\dfrac{2}{1}[/tex]
Hence, (a). Work done is the physical quantity which is same for both boys.
(b).Power is the physical quantity which is different for both boys.
The ratio of power of both boys is 2:1
A coffee machine transfers 12 kj of energy in 15 seconds. It uses 230 v mains supply. Use this information to work out the current through the coffee machine
The current through the coffee machine is 3.48 A.
To calculate the current flowing through the coffee machine, we use the formula below.
Formula:
E = VIt............. Equation 1Where:
E = Energy transfered by the machineV = Voltage of the main supplyI = current through the coffee,t = time.
Make I the subject of the equation.
I = E/Vt.............. Equation 2From the question,
Given:
E = 12 kJ = 12000 JV = 230 Vt = 15 seconds.Substitute these values into equation 2
I = (12000)/(230×15)I = 3.48 A.Hence, The current through the coffee machine is 3.48 A.
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Answer:3.48
Explanation:
Compound microscopes focus light through ______ to produce a magnified image.
Why does fitness matter?
Answer:
The great thing about exercise is that it’s never too soon or too late to start. Fitness can support healthy growth and development in children and reduce the risk of cognitive decline and delay the onset of dementia in older people. You don’t have to join a gym or spend lots of money on equipment to get fit.
Explanation:
Which force controls the size of an atomic nucleus?
1electromagnetic force
2weak nuclear force
3strong nuclear force
4gravitational force
Answer:
Strong nuclear force
Explanation:
Which statement compares how secondary earthquake waves and soundwaves move? A.Both can move through liquids. B.Neither can move through liquids. C.Secondary earthquake waves can move through liquids, but sound waves cannot. D.Sound waves can move through liquids, but secondary earthquake waves cannot.
Answer:
D
Explanation:
Secondary earthquake waves is a seismic wave that can travel through solid but cannot travel through liquid and gas.
This wave is one of the fastest traveling seismic waves.
While sound wave can travel through both solid and liquid and even gas.
Therefore, the statement that compares how secondary earthquake waves and soundwaves move is:
Sound waves can move through liquids, but secondary earthquake waves cannot.
The best answer is therefore D
A tissue cross-section viewed on a microscope slide shows a cell of almost rectangular shape with dimensions 6.9 × 10-4 cm by 1.1 × 10-3 cm. Calculate the cross-sectional area of the cell. Express the area in powers of ten notation and use the appropriate number of significant digits for the number multiplying the power of 10.
Answer:
The cross-sectional area is [tex]A = 7.59 *10^{-11} \ m^2[/tex]
Explanation:
From the question we are told that
The dimension of the cell is 6.9 × 10-4 cm by 1.1 × 10-3 cm = [tex]6.9*10^{-6} \ m \ by\ 1.1*10^{-5} \ m[/tex]
Generally the cross-sectional area is mathematically represented as
[tex]A = 6.9*10^{-6} * 1.1*10^{-5}[/tex]
=> [tex]A = 7.59 *10^{-11} \ m^2[/tex]
a car mass 1500kg traveling at a uniform velocity of 30 m/s due east .the driver applies the brake to slow down the car to a velocity of 10 m/s east . what is the work done in slowing down the car ?
Answer:
this is the answer
A graph of KE vs the mass of an object is __.
A graph of KE (kinetic energy) vs the mass of an object is a line, as we know that the kinetic energy depends linearly on the mass of the object.
What is kinetic energy?For an object of mass M moving with velocity v, we define its kinetic energy as:
KE = (M/2)*v^2
We can rewrite it as:
KE = (v^2/2)*M
So, it is a "coefficient" (if we assume that the velocity is constant) times the mass. That gives a linear relationship.
Then we conclude that the kinetic energy depends linearly on the mass, which means that the graph of KE vs the mass of an object is a line.
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Hydrogen is found as a gas on Earth but exists in all four states in the solar
system. Four samples of hydrogen have equal masses but are each in a
different state. Which statement about the relative amounts of thermal
energy in the samples is true?
Answer:the sample of solid has less energy than the sample of gas
Explanation:
Apex
A football has a mass of .43 kg and it accelerates at 20 m/s². What is its force?
Answer:
8.6N
Explanation:
We use the eq
F=ma
By putting values
F=.43×20
F=8.6N
Nikola Tesla and Thomas Edison were both pioneers when it came providing electricity to the people. Edison had hired the genius Tesla to work for him, but their differences, pride and personalities caused them to compete and publicly insult one another instead of working together. List 5 strategies these two could have used to help them work with others they disagree with.
Explanation:
In other to avoid a situation where their differences, pride, and personalities caused them to compete and publicly insult one another instead of working together they need to respectfully consider the viewpoints of each other, as well as assign individual roles that should be respected.
2. Can you rearrange the equation F = kx to get k on one side of the equation
(on its own!). Now, can you rearrange it to get x on its own?
k = f/x
x = f/k
( / means divide )
The equation connecting force and the displacement k is F= k x. From the spring constant k can be found by dividing F by x and similar to get x by dividing F by k.
What is force?Force is an external agent acting on a body to change it from the state of motion or rest. There are various kinds of force namely magnetic force, frictional force, gravitational force etc.
Force applied on a body if result in displacement of the body it is said to work done on the body. An elastic body like a spring can be stretched or compressed by applying a force on it. Let the change in length or displacement of the elastic body be x.
Then, the force applied on it to make the displacement x is directly proportional to x.
F = k x, where k is the proportionality constant here called the spring constant.
From this the spring constant k = F/x
Similarly, if we know the force f and spring constant k, then x = F/k.
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Two projectiles are fired at equal speeds but different angles. One is fired at angle of 30 degrees and the other at 60 degrees. The projectile to hit the ground first will be the one fired at (neglect air resistance) ____.
Answer:
14 degrees
Explanation:
because you can divide all and find the angle to find the answer
hope it's help ty make me brainless pls
Find magnitude of vector sum
Answer:
An airplane is flying at an airspeed of 200 miles per hour headed on a SE bearing of 140°. A north wind (from north to south) is blowing at 16.2 miles per hour, as shown in Figure 8.8.1. What are the ground speed and actual bearing of the plane?
Explanation:
plss brainlieist me
θ = 205° - 105° = 100°
[tex]\tt R=\sqrt{L^2+M^2+2LMcos\theta}\\\\R=\sqrt{303^2+555^2+2.303.555cos100}\\\\R=584.32~m[/tex]
When a car suddenly stops at a red light, a book lying on the car seat slides forward. Why does the book continue to move forward?
A. The book loses its backward momentum
B. The car moves in reverse more rapidly than the book
C. The friction of braking transfers energy to the book
D. The book’s inertia causes it to continue
Answer:
i think the answer is c if you get it wrong then it is b
Explanation:
Answer:
Your answer is: D) The book's inertia causes it to continue
Explanation:
Hope this helped : )
Which of the following is an example of an electric force acting at a distance?
A.
Pam rubs a glass rod with wool, then moves the rod over a pile of small paper scraps. The scraps leap into the air and stick to the rod.
B.
Pam applies a force to the head of a nail by pounding it with a heavy, iron hammer. The nail then wedges itself between the fibers of a wooden board.
C.
Pam applies a twisting force to the steering wheel of her car. This force pushes on tubes filled with fluid, which then push the wheels of her car to one side.
D.
Pam jumps out of an airplane. Air rushes past her body at
a very high speed as she falls. She then opens her parachute and feels an upward force.
Answer:
Option A
Explanation:
An electric force is a charged reaction that causes an attraction or a repulsion between two charged objects. In this case rubbing a glass rod with wool charges up the rod which then turns it into magnetic, which attracts the paper scraps from the ground to the rod where it sticks. The best answer is option A or "Pam rubs a glass rod with wool, then moves the rod over a pile of small paper scraps. The scraps leap into the air and stick to the rod."
Hope this helps.
The Sankey diagrams below show the
energy transfers in two light bulbs. The
useful energy output for these light
bulbs is carried to the energy stores of
the environment by
What
is the missing word?
1
8ØJ
Input energy
4ØJ
Useful energy
2
8ØJ
Input energy
1ØJ
Useful energy
The useful energy output for these light bulbs is carried to the energy stores of the environment by light waves.
Useful energy
The useful energy from the two light bulbs is the energy that is beneficial and consumed. This energy is said to be used to do meaningful work.
The useful energy from the two light bulbs illuminates the environment and enables us to see in the dark.
What is Light wave?A light wave is a type of electromagnetic wave that carries light energy. This light wave carries visible light into the environment.
The light from the two lights bulbs are visible lights and thus, the useful energy output for these light bulbs is carried to the energy stores of the environment by light waves.
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how is geothermal energy trapped? state a draw back of this kind of energy.
Answer:
Geothermal energy can be trapped using geothermal plants that utilizes steam escaping from the earth surface to make electricity.
The limitations include :
depletion of the geothermal sourcehigh costs of investments required for geothermal systemsExplanation:
Geothermal energy originates in form of heat/steam escaping from the inner parts of the earth surface. The steam trapped is converted to electricity through turbines. The hot water pumped by heat pumps can be used to heat homes or for heating purposes in industries.
The limitations of geothermal energy are high initial capital costs for installing the systems, depletion of geothermal sites after sometime, environmental concerns due to greenhouse gases emissions and land requirements for geothermal projects.
4. A girl places a stick at an angle of 60.0° against a flat rock on a frozen pond. She pushes at an angle and moves the rock horizontally for 2.00 m across the pond at a velocity of 4.00 m/s and a power of 160.0 W. What force did she apply to the stick? How much work did she do? Your response should include all of your work and a free-body diagram
Answer:
Below!
Explanation:
At a given temperature, 3.00 m of carbon dioxide has a mass of 5.94 kg. What is the density of carbon dioxide at this temperature
Answer:
1.98 kg/m
Explanation:
5.94 divided by 3.00
What kind of combination of mass, fan speed, and surface is best for taking
the most mass across the 500 cm of track, but keeping it under 80 cm/sec,
which is a standard for safety in this cart type.
Answer:bro I need someone to help me with this question too what did you awser
Explanation:
Please help!!! I’ll
mark brainliest!
Answer:
D, the weight
Explanation:
Normal force is mass times gravity
gravity help determines weight
Also a,b and c are all vectors and D is a scaler
An airplane is traveling 200 mph south. You get up and walk down the aisle at 1 mph north. Your resultant velocity is
Quarterback backpedals 2.5 M northward and then runs 6.8 M Southward what is the magnitude and direction of the displacement
Answer:
4.3
Explanation:
because 6.8 subtracted by 2.5 is 4.3