Answer:
The conservation of momentum of a system is a fundamental principle in classical mechanics. The only condition for this principle being valid is that the system should be an isolated one, i.e. It should not be acted upon by any external force.
A hair dryer transforms 10,000J of energy in 4s. What is its power?
Answer:
2500 WExplanation:
Power is the rate at which work is done and can be found by using the formula
[tex]p = \frac{w}{t} \\ [/tex]
p is power in Watts ( W)
w is the workdone in J
t is time in s
From the question
w = 10,000 J
t = 4 s
We have
[tex]p = \frac{10000}{4} = 2500 \\ [/tex]
We have the final answer as
2500 WHope this helps you
A heavy crate is pushed across a floor at a constant velocity. Friction is present between the crate and floor. During this motion, the force of friction is _?_ the force pushing the crate forward.
Question 3 options:
less than
greater than
equal to
Answer:
less than.
Explanation: because Friction is the resistance to motion of one object moving relative to another. which means it cant be greater because how would it be greater if its pushing forward when friction is the resistance.
THANKS FOR THE POINTS :D
The position as a function of time for two objects moving along a straight line is shown in the graph,
Which statement is true about the distances the two object have traveled at time ty?
Object 1 has traveled a greater distance.
B
Object 2 has traveled a greater distance.
Both objects have traveled the same distance
D
The total distance traveled by each object cannot be compared using the graph.
The distance traveled by object 1 is greater than the distance traveled by object 2.
The shortest distance between two points is a straight line. More distance is covered when the path of motion is curved.
The distance traveled by each object at different time is compared as follows;
[tex]at \ t_ A , \ \ \ d_1>d_2 \ \ \ (d_2 = 0)\\\\at \ t_B, \ \ d_1 > d_2 \\\\at \ t_C, \ \ \ d_2 > d_1 \\\\at \ t_D \ \ \ d_1 = d_2\\\\at \ t_f \ \ \ d_2 > d_1 \ \ \ (d_1 = 0)[/tex]
The major distinguishing distance traveled by each occurs at [tex]t_B[/tex] and [tex]t_C[/tex].
[tex]d_{(t_B)} > d_{(t_C)} \\\\d_1 > d_2[/tex]
Thus, we can conclude that the distance traveled by object 1 is greater than the distance traveled by object 2.
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can someone explain it please ?
Answer:
The value of [tex]\theta=63.43^0[/tex]
Explanation:
Range of projectile [tex]\mathrm{R}=\frac{\mathrm{u}^{2} \cdot \sin 2 \theta}{\mathrm{g}}[/tex]
Height of projectile [tex]\mathrm{h}=\frac{\mathrm{u}^{2} \cdot \sin ^{2} \theta}{2 \cdot \mathrm{g}}[/tex]
Here we have
[tex]R=2h\\\\\frac{\mathrm{u}^{2} \cdot \sin 2 \theta}{\mathrm{g}}=2\frac{\mathrm{u}^{2} \cdot \sin ^{2} \theta}{2 \cdot \mathrm{g}}\\\\\sin 2 \theta=\sin ^{2} \theta\\\\2\sin \theta\cos \theta=\sin ^{2} \theta\\\\\tan \theta=2\\\\\theta=63.43^0[/tex]
Range be R and height be h
[tex]\boxed{\sf R=\dfrac{u^2sin2\theta}{g}}[/tex]
[tex]\boxed{\sf h=\dfrac{u^2sin^2\theta}{2g}}[/tex]
u=initial velocitytheta is angle of projection.g=acceleration due to gravityATQ
[tex]\\ \sf\longmapsto R=2h[/tex]
[tex]\\ \sf\longmapsto \dfrac{u^2sin2\theta}{g}=\dfrac{2u^2sin^2\theta}{2g}[/tex]
Cancelling required ones[tex]\\ \sf\longmapsto sin^2\theta=sin2\theta[/tex]
sin2O=2sinOcosO[tex]\\ \sf\longmapsto sin^2\theta=2sin\theta cos\theta [/tex]
[tex]\\ \sf\longmapsto \dfrac{sin^2\theta}{sin\theta cos\theta=2[/tex]
[tex]\\ \sf\longmapsto \dfrac{sin\theta}{cos\theta}=2[/tex]
[tex]\\ \sf\longmapsto tan\theta=2[/tex]
[tex]\\ \sf\longmapsto \theta=tan^{-1}(2)[/tex]
[tex]\\ \sf\longmapsto \theta=63.4°[/tex]
why is water soaked cloth used on forehead during fever?please can you tell me answer
This is because the cloth soaked in water can absorb and evaporate the heat from your forehead.
Explanation:This technique is used to cool down your fever, and to help you feel better.
Which metals can be extracted from following ores (i) Argentite (ii) Haematite (iii) Chalcopyrite (iv) Bauxite
I hope it's helpful for you ☺️
1) iron
2) aluminium
3) silver
4) copper
Define "one solar day".
Answer:
the interval between transits of the apparent or mean sun across the meridian at any place.
which is the correct relationship among pressure, flow, and resistance?
Answer:
Flow is proportional to change in pressure and inversely proportional to resistance.
how does gravitational lensing tell us about the mass of a galaxy cluster?
Answer:
Newton's universal law of gravitation predicts how mass can distort light, so we can apply Newton's law to determine the mass of the cluster. ... The lensing allows us to determine the orbital speeds of galaxies in the cluster, so that we can determine the mass of the cluster from the orbital velocity law.
Explanation:
a car dealer sells 4 makes of cars in 5 colors with either standard or automatic transmissions. how many variations does the dealership offer?
The number of variations the dealership have is 40 cars.
Data given;
The number of different product = 4The number of transmission = 2 (standard or automatic)The numbers of colors available = 5Dealership variationThis is the total numbers of cars available in the dealer shop at the moment.
To get that, we simply multiply the numbers of colors available, the number of transmission and the makes of car available.
This is equal to
[tex]4*2*5=40[/tex]
From the above calculation, we can say that the variations the dealership offers is 40
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You are pulling a friend on a sled with a constant velocity using a rope held
horizontally in the snow. Using a spring scale attached to the rope, you
measure the tension to be 112 N. The combined mass of the sled and your
friend is 57.4 kg. Write the surface force the ground exerts on the sled in
component form, and determine its magnitude.
Here are all the steps.
When you are pulling a sled with constant velocity with a rope then the ground exerts a surface force on the sled will be equal to 573.56 N.
What is tension?The pulling force delivered axially by a cable, string, chain, or by either end of a rod, truss member, or another such 3-D object is known as tension in physics. Tension can be described as the action-reaction pair of forces acting at each end while tension is a polar opposite of compression.
A restoring force causes tension when atoms or molecules are torn apart at the atomic level and build up potential energy.
When you are trying to move upward and push in a positive way,
F = - 112 i + 57.4 (9.8) j
F = -112 i + 562.52 j
[tex]F = \sqrt{(-112)^2+ (562.52)^2}[/tex]
[tex]F =\sqrt{12544 + 316428.7}[/tex]
F = 573.56 N
Therefore, the surface force the ground exerts on the sled is 572.52 N.
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calculate the resultant force acting on the object and state its direction
[tex]\\ \sf\Rrightarrow F_{net}=F_1+F_2+F_3+F_4[/tex]
[tex]\\ \sf\Rrightarrow F_{net}=20N+20N+10N-10N[/tex]
[tex]\\ \sf\Rrightarrow F_{net}=40N[/tex]
Direction is east.how to calculate kinetic energy given mass and velocity
In classical mechanics, kinetic energy (KE) is equal to half of an object's mass (1/2*m) multiplied by the velocity squared. For example, if a an object with a mass of 10 kg (m = 10 kg) is moving at a velocity of 5 meters per second (v = 5 m/s), the kinetic energy is equal to 125 Joules, or (1/2 * 10 kg) * 5 m/s2.
In the United States, radioactive waste is divided into three main categories based on their activity, their heat generation potential, and what they physically contain.
Low level radioactive waste is the least dangerous type of nuclear waste. It contains relatively small amounts of radioactive substances with short half-lives.
Which of the following methods is most commonly used to dispose of low level radioactive wastes?
A.
activating reactions so the material is no longer radioactive
B.
sealing the waste into steel tanks and burying the tanks deep into the ground
C.
compacting the waste and burying it in a shallow landfill
D.
sealing in a biohazard bag and disposing the bag with ordinary trash
Answer:
C.Compacting the waste and burying it in a shallow landfill.
Explanation:
It is buried in a shallow landfill because it is less reactive.
It takes a car 4 seconds to slow down from 22 m/s to 6 m/s , what was its acceleration?
To Find The Acceleration of A Car Slowing Down:
The change in speed is the final speed minus the initial speed. To find acceleration, divide the change in velocity by the length of time during which the velocity changed.
When Magnesium and Fluorine react what type of bond is formed
A) Metallic
B) Ionic
C) Covalent
D) Diatomic
Answer:
hi your answer should be B
Explanation:
Hope this helps!
Answer:
ionic
Explanation:
two metals that bond are considered ionic bonds
A wave completes one vibration as it moves a distance of 2 meters at a speed of 20 meters per second. What is the frequency of the wave?
I need the Formula,Known,Substitute & Solve Answer with Units
Answer:
I put the answer
Explanation:
Can you see it
10Hz is the frequency of the wave.
How to find the frequency of the wave?
To calculate the frequency of a wave, divide the velocity of the wave by the wavelength. Write your answer in Hertz or Hz
Given,
F = 2
λ=2m
v=20m/s
By applying the formula, we get
V = Fλ
F = V / λ
F = 20 / 2
=10Hz
Wave frequency is the number of waves that pass a fixed point in a given amount of time.
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45. 3. (III) A 7.26 kg bowling ball hangs from the end of a 2.5 m rope. The ball is pulled back until the rope makes an angle of 45 with the vertical. a. What is the increase in the ball’s potential energy when it is lifted? b. If the ball is released from rest and swings downward like a pendulum, how much kinetic energy will the ball have at the bottom of its swing? c. How fast will the ball be moving at the bottom of its swing?
Explanation:
For the first question look at the picture. It should be pretty clear. Remember that cos45° = sqrt2 / 2.
2) We calculate it thanks to the conservation of mechanical energy:
Em1 = Em2
U1 + K1 = U2 + K2
K1 = 0J
U2 = 0j
U1 = K2
3) mgh = 1/2mv^2
v = sqrt(2gh)
At which point does a substance have the greatest amount of kinetic energy
PLEASE HELP also i know this isnt physics but there was no HOPE/Gym subject for me to choose.
Answer:
Plan B.
Because flexibility is best improved by stretching.
Explanation:
Improving and increasing flexibility is done by having stretching sessions daily which maintains and widens the range of motion in the joints and stretches muscles.
why is creavity important inn constructing scientific methods
1) A creative method can save money when you have limited resources
2) A scientific experiment is always very boring
3) There is only one experiment that can test each hypothesis
4) There is no creativity in the scientific community.
Answer:
The answer is C
Explanation:
Scientists use creativity to determine which smaller questions are likely to yield results, imagine possible answers to their questions, and devise ways to test those answers.
Creativity is the key to make the scientific experiments more efficient and and economic and hence, a creative method can save money when you have limited resources.
What is a scientific method?A scientific method is constituted by a set of stages and instructions to conduct a scientific experiment to attain a possible solution for a problem. Scientific methods have to be reproducible and effective to bring a valid solution for a hypothesis based on an observation.
Creative thinking is always paramount significance because it leads more ways and identifies the pitfalls in the available scientific methods. Creativity improves the way of designing a scientific experiments and to gather informations also.
Therefore, creative method can save money when you have limited resources is a true statement regarding a scientific method.
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The length of daylight changes as the seasons change during the year. what causes these changes in the number of daylight hours?
Answer:
The earth travels around the sun in a (parabolic) path known as the ecliptic.
The axis of the earth's rotation is tilted about 23 deg to the ecliptic.
At the winter solstice (around Dec. 21), the sun will appear to be at its farthest south in its orbit. (This marks the beginning of winter for observers in the northern hemisphere and the beginning of summer for an observer in the southern hemisphere)
The tilt of the axis of the earth's rotation causes the change in the daylight hours.
7. a heater heating up the inside of the car
Convection conduction and radiation
Yoo what it do I don’t know the answer tho
Answer:
You should try your best to answer the question.
I desperately need help with my Physics Exam I am failing this class will mark Brainliest to whoever helps the most: PART 1 (I don't want to overwhelm anyone so I'm posting my questions in parts) Also the questions marked are incorrect, so just work with the 3 remaining answers.
10000000 thank you's
when an individual charge flies through a *blank* field, a force is exerted on the charge and the path of the charge bends.
Answer:
"electric or magnetic"
F = q E force on charge q due to electric field E
F = q v x B force on charge q due to magnetic field B
does a perfectly elastic colission conserve momentum and impulse
Answer:
A perfectly elastic collision conserves momentum and kinetic energy..
You want to replace the resistor in your
boiler with a more efficient one during win-
tertime. Would you replace it with another
one double the length or half the length?
To make the boiler more efficient, we would replace the resistor with another double the length.
We know that the resistance of the resistor in the boiler is given by R = ρl/A where
ρ = resistivity, l = length of resistor and,A = cross-sectional area of resistor.Also, the power generated by the resistor is P = i²R where
i = current and R = resistance.If i is constant, we see that P ∝ R.
So, to increase the efficiency, the value of the resistance has to increase.
Also, since R = ρl/A and ρ and A are constant, we see that R ∝ l.
Since P ∝ R and R ∝ l ⇒ P ∝ l.
So, to increase the efficiency, we would double the length of the resistor.
So, to make the boiler more efficient, we would replace the resistor with another double the length.
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A bus accelerates away from the bus stop at 2.5 m/s2
.
The total mass of the bus and passengers is 14 000 kg.
Calculate the resultant force needed to accelerate the bus and passengers.
help pls my brain is not working
Explanation:
F=k.g m\s2
=2.5 m\s2 14000k.g
= 35000N
what does the slope of the curve on a velocity vs. time graph represent?
Answer:
the slope of velocity-time graph represent an object acceleration