Answer:
Explanation:
For acceleration due to gravity g , the expression is
g = GM / R² , where G is gravitational constant M is mass of the earth and R is radius of the earth .
At height h , let the value of it becomes g / 4 , so
g / 4 = GM / ( R + h )²
dividing
4 = [( R+ h)² / R² ]
2 = (R + h) / R
2 = 1 + h / R
h / R = 1
h = R
So at height equal to radius of the earth , acceleration due to gravity becomes 1 /4 of value on the surface of the earth .
A machine can never be 100% efficient because some work is always lost due to which factor? friction gravity static input force
Explanation:
Hi,
The answer is friction.
There is almost no machine which are not affected by friction. It losts some work due to friction while working.
Hope it helps..
Answer:
friction
Explanation:
the other options dont effect efficiency
A laser beam is incident on two slits with a separation of 0.210 mm, and a screen is placed 5.05 m from the slits. If the bright interference fringes on the screen are separated by 1.59 cm, what is the wavelength of the laser light?
Answer:
0.66*10^-6m
Explanation:
We know that the bright fringes are placed on the screen as follows
Ym= m*(lambda xL/d)
But we are given
L= 5.05
Deta Y= 1.59
d = 0.21
1.59* 10^-2m= lambda * 5.05m/2.1*10^-4m
So lambda=
1.59* 10^-2m x 2.1*10^-4m/ 5.05m
= 0.66*10^-6m
If the s – t graph of a particle is parallel to the t – axis, the speed of the particle is (a) zero (b) constant (c) infinite (d) non-uniform
Answer:
(b) constant
Explanation:
parallel to t - axis means, at all the times, the s component does not change, it remains same, i. e., the speed is constant.
:-)
Answer:
zero
Explanation:
if the velocity time graph is parallel to the time axis its mean body has not covered the path in other words body is at rest.So the velocity of the body should be zero
so the speed is zero
hope my answer will help u
Which of the following best describes a consumer?
0. a business owner who sells clothes
0. someone who studies economics
O. a farmer who sells his crops
O. a person who buys goods and services
Answer:
a business who buys goods and services
HELPPP!! ASAPPP!! PLEASEEE
Answer: 9.675 Hz .
Explanation:
Given, velocity of waves = 12.9 m/s
Length of string = 2.00 m
Let [tex]\lambda[/tex] be the wavelength , then for 3 loops
[tex]\dfrac{3}{2}\lambda= \text{length of string}\\\\\Rightarrow\ \dfrac{3}{2}\lambda= 2\ m\\\\\Rightarrow\ \lambda= \dfrac{4}{3}\ m[/tex]
Now , velocity = frequency x wavelength
Then, frequency = [tex]\dfrac{velocity}{wavelength}[/tex]
[tex]=\dfrac{12.9\times3}{4}\\\\=9.675\ Hz[/tex]
hence, it will create standing waves with 3 loops at 9.675 Hz .
Which example best describes a restoring force?
any force that is applied to a spring to change its length
the force applied to stretch a spring and increase its length
the force applied to restore a spring to its original length
the force applied to compress a spring and shorten its length
Answer:
the force applied to restore a spring to its original length
Explanation:
A 210 Ohm resistor uses 9.28 W of
power. How much current flows
through the resistor?
(Unit = A)
Current=I
[tex]\boxed{\sf P=I^2R}[/tex]
[tex]\\ \sf\longmapsto I^2=\dfrac{P}{R}[/tex]
[tex]\\ \sf\longmapsto I^2=\dfrac{9.28}{210}[/tex]
[tex]\\ \sf\longmapsto I^2\approx0.04[/tex]
[tex]\\ \sf\longmapsto I\approx\sqrt{0.04}[/tex]
[tex]\\ \sf\longmapsto I\approx\sqrt{\dfrac{4}{100}}[/tex]
[tex]\\ \sf\longmapsto I\approx\dfrac{\sqrt{4}}{\sqrt{100}}[/tex]
[tex]\\ \sf\longmapsto I\approx\dfrac{2}{10}[/tex]
[tex]\\ \sf\longmapsto I\approx0.2A[/tex]
Which of the following statements regarding the visible spectrum of light is
accurate?
It represents only a very small fraction of the entire electromagnetic spectrum.
O It can be detected only through the use of thermal imaging equipment.
The wavelength of visible light falls between gamma rays and X-rays along the
spectrum.
It has the longest wavelength of all types of waves along the electromagnetic
spectrum
Answer:
It represents only a very small fraction of the entire electromagnetic spectrum.
Explanation:
The visible spectrum of light makes up only a very small part of the electromagnetic spectrum. The wavelength of visible light is longer than ultraviolet waves but shorter than infrared waves.
An electric lamp is marked 240v, 60w
It is left to operate for 1h. How much
heat is generated by the lamp
Answer:
H = 0.06 kWh
Explanation:
Given that,
Power of an electric lamp, P = 60 W
Voltage, V = 240 V
It is operated for 1 hour
We need to find the heat generated by the lamp. Heat generated is given by :
[tex]H=P\times t\\\\H=60\ W\times 1\ h\\\\H=60\ Wh\\\\H=0.06\ kWh[/tex]
So, 0.06 kWh of the heat is generated by the lamp.
Define Metrology
define Metrology
Answer:
the scientific study of measurement.
A rabbit runs a distance of 60 meters in 20s. What is the average speed?
Answer:
3 m/s
Explanation:
Given,
Total distance = 60 m
Total time = 20 s
We know that,
Average speed = Total distance/Total time
=> Average speed = 60 m/20 s
=> Average speed = 3 m/1 s
=> Average speed = 3 m/s
Average speed=Total distance/Total time
[tex]\\ \sf\longmapsto Average\:Speed=\dfrac{60}{20}[/tex]
[tex]\\ \sf\longmapsto Average\:Speed=3m/s[/tex]
in order for the average velocity to be different from the avergae speed, what has to be true of the object's motion?
Answer:
ok
Explanation:
Acceleration is defined as the rate of change of velocity.
Acceleration = (Change in velocity) / time taken
Acceleration = (Final velocity - initial velocity) / time
As the object velocity changes by the same amount in each second, it means the acceleration is constant.
Select the correct answer. Ben has $10 to spend on dinner. He can have a pizza delivered, drive to a burger place, or go to the grocery store to get ingredients for a fresh salad. In the end, he goes with the salad. If each meal would have cost him the same amount, what is Ben’s incentive for choosing salad? A. to eat a healthier meal B. to help the local economy C. to save gas D. to save on his telephone bill
Answer:
A. to eat a healthier meal
Explanation:
The answer would be A, to eat a healthier meal. Eating a serving of mixed greens can enable Ben to shed pounds in the event that it encourages you to diminish your aggregate calorie admission. Pick filling fixings with the goal that you are not as ravenous and eat less, and keep your plates of mixed greens low in calories so they give fewer calories than the feast or tidbit that they are supplanting.
Which are the two most popular candidates for gamma-ray bursters? Group of answer choices collisions between a white dwarf and a giant, and merger of two neutron stars hypernova making a black hole, and merger of two neutron stars formation of uranium in the core of a supergiant, and collisions of white dwarfs mergers of two black holes, and merger of a neutron star and a white dwarf hypernova making pulsars, and mergers of two white dwarfs
Answer:
hypernova making a black hole, and merger of two neutron stars
Halley is standing outside on a cloudy day. When she hears thunder, she goes back inside so that she doesn't get caught in
a storm. Is this an example of inference or prediction? Explain
Answer:
Inference
Explanation:
An inference involves the application of logic to progress from a premise to a conclusion or logical consequence on the basis of the evidence or known fact. Inference is a process of thought that be divided into a deduction and an induction aspect.
In the given question Halley, by standing outside was able to deduce the sound of thunder she is then able by inductive reasoning from the fact that storms are usually preceded by and accompany lightening, conclude that there is a storm coming.
A 5000 g toy car starts from rest and moves a distance of 300 cm in 3 s under the action of a single constant force. Determine the magnitude of the force? help good answer please
Answer:
3.33 N
Explanation:
First, find the acceleration.
Given:
Δx = 3 m
v₀ = 0 m/s
t = 3 s
Find: a
Δx = v₀ t + ½ at²
3 m = (0 m/s) (3 s) + ½ a (3 s)²
a = ⅔ m/s²
Use Newton's second law to find the force.
F = ma
F = (5 kg) (⅔ m/s²)
F ≈ 3.33 N
A narrow beam of light containing red (660 nm) and blue (470 nm) wavelengths travels from air through a 1.00 cm thick flat piece of crown glass and back to air again. The beam strikes at an incident angle of 30 degrees. (a) At what angles do the two colors emerge
Answer:
The color blue emerges at 19.16° and the color red emerges at 19.32°.
Explanation:
The angle at which the two colors emerge can be calculated using the Snell's Law:
[tex]n_{1}sin(\theta_{1}) = n_{2}sin(\theta_{2})[/tex]
Where:
n₁ is the refractive index of the incident medium (air) = 1.0003
n₂ is the refractive index of the refractive medium:
blue light in crown glass = 1.524
red light in crown glass = 1.512
θ₁ is the angle of the incident light = 30°
θ₂ is the angle of the refracted light
For the red wavelengths we have:
[tex] \theta_{2} = arcsin(\frac{n_{1}sin(\theta_{1})}{n_{2}}) = arcsin(\frac{1.0003*sin(30)}{1.512}) = 19.32 ^{\circ} [/tex]
For the blue wavelengths we have:
[tex] \theta_{2} = arcsin(\frac{n_{1}sin(\theta_{1})}{n_{2}}) = arcsin(\frac{1.0003*sin(30)}{1.524}) = 19.16 ^{\circ} [/tex]
Therefore, the color blue emerges at 19.16° and the color red emerges at 19.32°.
I hope it helps you!
A driver of a car stopped at a gas station to fill up his gas tank. He looked at his watch, and the time read exactly 4 : 45 4:45 p.m. At this time, he started pumping gas into the tank. At exactly 4 : 50 4:50, the tank was full and he noticed that he had pumped 12.5 12.5 gallons. What is the average rate of flow of the gasoline into the gas tank
Answer:
Explanation:
Average rate = gallons / minutes
If 12.5gallons in 5mins
Xgallons in 1mins
12.5/5 = 2.5gallons per minute
The Coulomb force between two charges q1 and q2 at separation r in air is F. If half of the separation is filled with medium of dielectric constant 9, what will be the value of new coulomb force?
Answer:
The new Coulomb force is q₁q₂/9πε₀r²
Explanation
The coulomb force between the two charges q₁ and q₂ at a distance r in air is given by F = q₁q₂/4πε₀r².
Now, let us assume the material of dielectric constant κ = 9 is placed between them on the side of the q₁ charge. The value of its effective charge is now q₃ = q₁/κ at a distance of d = r/2 from the q₂ charge.
Since we have air between q₂ and q₃, the coulomb force between them is
F' = q₂q₃/4πε₀d²
= q₂(q₁/κ)/4πε₀(r/2)²
= 4q₂q₁/κ4πε₀r²
= 4/κ(q₂q₁/4πε₀r²)
= 4/9 × (q₂q₁/4πε₀r²)
= q₁q₂/9πε₀r²
So, the new Coulomb force is q₁q₂/9πε₀r²
The law of conservation of momentum states that the total momentum of interacting objects does not _____. This means the total momentum _____a collision or explosion is equal to the total momentum _____ a collision or explosion.
Answer:
The law of conservation of momentum states that the total momentum of interacting objects does not change. This means the total momentum before a collision or explosion is equal to the total momentum after a collision or explosion.
Answer:
The answer is
Explanation:
Change. Does not change.means.
Hope this helps....
Have a nice day!!!!
a object 1.5cm high produces a real image 2cm high. placed at a distance of 20cm
from a concave mirror calculate: [a] the position of the image [b] focal lenght of the concave mirror
Answer:
a. 26.7 cm. b. 11.4 cm.
Explanation:
a. We know h'/h = d'/d where h' = image height = + 2 cm (since it is a real image), h = object height = + 1.5 cm, d' = image distance from mirror and d = object distance from mirror = 20 cm
So, from h'/h = d'/d
d = h'd/h
= 2 cm × 20 cm/1.5 cm
= 40/1.5 cm
= 26.67 cm
≅ 26.7 cm
The position of the image is 26.7 cm from the mirror
b. Using the mirror formula
1/d + 1/d' = 1/f where d = object distance from mirror = + 20 cm, d' = image distance from mirror = + 26.7 cm (its positive since its a real image) and f = focal length of mirror.
So, 1/d + 1/d' = 1/f
⇒ f = dd'/(d + d')
= 20 cm × 26.7 cm/(20 cm + 26.7 cm)
= 534/46.7
= 11.43 cm
≅ 11.4 cm
The focal length of the mirror is 11.4 cm
7 (a) Smoke particles are introduced into a glass box containing air. Light shines into the box so that, when observed through a microscope, the smoke particles can be seen as bright points of light. Describe the motion of the smoke particles and account for this motion in terms of the air molecules.
Answer:
smoke particles move in brownian motion (zig -zag motion ) .
Explanation:
this is because air molecules collide against smoke particles hence they attain kinetic energy which keeps them in continuous motion .
The motion of the smoke particles is Brownian motion that is the zigzag motion of the particles that particles move in a random direction.
What is a Brownian Movement?In chemistry, the term "Brownian Movement" refers to the random zigzagging motion of a particle that is typically seen under a high power ultra-microscope. The term "Brownian movement" refers to the exact motion of pollen grains in water, as described by Robert Brown.
More crucially, Albert Einstein eventually clarified the Brownian movement in his study by claiming that water molecules were responsible for moving the pollen. This discovery provided compelling proof that atoms and molecules exist.
According to the question, the reason is that air molecules collide against smoke particles, hence the particles get kinetic energy which keeps them in continuous motion or in zigzag motion.
To get more information about Brownian Movement :
https://brainly.com/question/20350065
#SPJ2
An object is moving across a surface, but it does not gain or lose speed. Which best describes the object's force?
O The net force is positive.
O The net force is zero.
The positive force is greater than the negative force.
O The negative force is greater than the positive force.
Mark this and retum
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Submit
Answer:
The net force is positive
Explanation:
This would mean that altogether, the force would cause the object to always be going the same way, and if it is not gaining or losing speed, we can say the force has not changed and that the object has reached terminal velocity. It is not correct to say that the positive is greater than the negative as friction also causes some type of effect and it is neither positive nor negative
Hi :) how to do this?
Answer:
The answer is b
Hope this helps you!
what is physics and important of physics
Answer:
Confusion
question:
is it multiple choice? or you have to write it
9. An object of weight 80kg on earth is taken to a
planet where the acceleration due to the gravity is one-
third of its value on earth. The weight of the object on
the planet is
Answer:
266. 4
Explanation:
acceleration due to vravity on earth is 10m/s.
One third of it is (1/3)*10
=3.333m/s.
Weight is mass × acceleration
weight= 80kg÷ 3.333m/s
W= 266.4 Newton.
A cat stalks an unsuspecting mouse. The movement of the cat is shown in the following graph of the horizontal position, x, against time, t. What is the average speed of the cat between t = 2s and t = 6s?
Answer:
0.25 m/s
Explanation:
Average velocity = change in displacement / change in time
v = (1.5 m − 2.5 m) / (6 s − 2 s)
v = -0.25 m/s
The average speed is 0.25 m/s.
Answer:
0.25 m/s
Explanation:
khan academy
At a camp site there are tents of 2 shades. 1 made with black fabric and the other with white fabric. Which one will you prefer for resting on a hot summer afternoon. Give reason for your choice
Answer:
Explanation:
On a hot summer afternoon the tent made up of white fabric will be preferred because white colour is a bad absorber and good reflector of heat. Hence, it will be more convenient to stay under fabric tent made of white during this season because heat will be reflected which makes shade provided by such tent to be cool and enjoyable.
While the black fabric tent will be preferred during winter because black materials are good absorber of heat and are poor reflector.
What does physics means to you. (own words)
Answer:
the physical properties and phenomena of some thing.
In explannation
Physics is a branch of science. It is one of the most fundamental scientific disciplines. The main goal of physics is to explain how things move in space and time and understand how the universe behaves. It studies matter, forces and their effects. The word physics comes from the Greek .
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What is the total distance covered during its complete motion? (CCT TYPE) *
2 points
350 km
20/3 km
50 km
40/3 km
What is the SI unit of speed? ( CCT type) *
2 points
m/s
mm/s
m/ss
None of the above
. In which period is the bus decelerating? (CCT type) *
2 points
0-5 min
8- 12 min
11-19 min
5-10 min
Only answer who knows, don't spam. because I am in hurry.
Answer:
40/3
M/s
11-19
These are the answers