a ray of light is incident in water at angle of 30 on water air plane mirror surface .find the angle of refraction in air.
Angle of incidence=angle of refraction
[tex]\\ \sf\longmapsto sin\:i=sin\:r[/tex]
sin i=30°[tex]\\ \sf\longmapsto sin\:r=30°[/tex]
help me with b and d please
A 65 kg diver stands still on a tower, 100 m above the water
(a) Calculate the gravitational potential energy of the diver, relative to the height of the water. Assume the gravitational field constant is 9.8 N/kg
(b) The diver reaches the surface of the water at a speed of 14 m/s. Calculate the diver's kinetic energy
(c) Compare your answers to (a) and (b). Explain your comparison using concepts learned in this course.
Assume there is no air resistance during the dive (d) Calculate the speed of the diver 5.0 m above the water.
Following are the solution to the given points:
Given:
[tex]\to mass(m)= 65\ kg\\\\\to h=10.0 \ m\\\\\to g=9.8 \ \frac{m}{s^2}[/tex]
To find:
gravitational potential energy(GPE)=?
kinetic energy(KE)=?
concept=?
v=?
Solution:
For point a:
[tex]\to GPE= mgh[/tex]
[tex]= 65 \times 10 \times 9.8\\\\ = 6370 \ J\\\\[/tex]
For point b:
[tex]\to KE=\frac{1}{2} m v^2\\\\[/tex]
[tex]=\frac{1}{2} \times 65 \times 14^2 \\\\=\frac{1}{2} \times 65 \times 14 \times 14 \\\\= 65 \times 14 \times 7 \\\\=6370\ J\\[/tex]
For point c:
As we've seen, there really is no force acting, and the mechanic KE: GPE is used. Because legitimate is conserved. Home energy loss means GPE must be equal to KE gain.
For point d:
A diver has risen 5 feet above the surface. As a result, according to the energy conservation law:
[tex]\to U_i + K_i= U_f + K_f\\\\ \to mg \times h + 0 = mg \times \frac{h}{2} + \frac{1}{2} m v^2\\\\ \to 9.8 \times 10 = 9.8 \times 5 + \frac{v^2}{2}\\\\\to 9.8 \times 10 - 9.8 \times 5 = \frac{v^2}{2}\\\\\to \frac{v^2}{2} =9.8( 10 - 5) \\\\\to v^2 =9.8( 10 - 5) \times 2 \\\\\to v^2 =9.8\times 5 \times 2 \\\\\to v^2 =98 \\\\\to v =98\ \frac{m}{s^2} \\\\[/tex]
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Answer:
wash or dry cleanmeasuring tapeupper arm girthtapeheightmeasuring tapebistlinewaistlineabdomenhip or seatExplanation:
please mark brainiest
How to find force if mass time and distance is given?
Answer:
For example, speed is a length divided by time. Force is mass times acceleration, and is therefore a mass times a distance divided by the square of a time. We therefore say that [Force] = MLT−2.
Which statement describes how nuclear power generation systems work?
O A.
The heat for the electricity generation process comes from nuclear fusion.
ов.
Electricity is generated directly when two atoms split into smaller ones.
O C.
The heat for the electricity generation process comes from nuclear fission.
OD.
Electricity is generated directly when two atoms join together.
Answer:
c- heat for electricity generation process comes from nuclear fission
Explanation:
nuclear fission is splitting of atoms to release energy held at nucleus of atoms
A heavy train of mass 200 tonnes has a maximum speed of 20m/s up a hill inclined at 1.15⁰ to the horizontal when the engine is working at 800 kwatts. What is the resistance to the motion of the train?
Answer:
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Explanation:
click the link the answer is in the link:)
Answer:
train to busan
shadow train
the horror train
train game
A car drives around a racetrack for 30 seconds. What do you need to know to
calculate the instantaneous speed of the car at a given point?
A. The total displacement of the car
B. The time needed to drive 1 lap
C. The slope of the car's position-time graph
D. The average speed of the car
Answer: the slope of the cars position-time graph
Explanation:
Just took the test
Which statement about magnetic force is FALSE?
5. Sarah is standing 32.0 m away from Jason. If Sarah throws a snowball at a 45 degree
angle for maximum distance, what velocity must the snowball have to hit Jason directly.
(Assume Jason and Sarah are about the same height so that if she throws the snowball
from head level, it will hit Jason in the head.)
Answer:
Explanation:
If air resistance is ignored and assume UP and Toward Jason are the positive directions.
horizontal analysis
d = (vx₀)t
t = d/vx₀
horizontal analysis
0 = vy₀t + ½gt²
0 = vy₀(d/vx₀)+ ½g(d/vx₀)²
as vy₀ = v₀sin45 and vx₀ = v₀cos45 and are equal.
0 = d + ½g(d²/v₀²cos²45)
-d = ½g(d²/v₀²cos²45)
-dv₀² = ½g(d²/cos²45)
v₀² = -½g(d/cos²45)
v₀² = -½(-9.81(32.0/cos²45)
v₀² = 313.92
v₀ = 17.717787...
v₀ = 17.7 m/s
Why might a scientist use a physical model of a plant cell instead of studying
a cell directly?
A. A model can be used for things that are too hot to handle easily.
B. A model can be used for things that are too small to see clearly.
C. A model can be used for things that are too large to study directly.
D. A model can be used for things that are too simple to study
directly
B. A model can be used for things that are too small to see clearly
What happens when acetate rubs with wool
When a Cellulose Acetate rod is rubbed with a woolen duster, friction occurs, rubbing loosely held electrons from the rod onto the duster. So, this time, the rod loses electrons. Since the Acetate rod now has fewer electrons than protons it has become positively charged. Hope this helps!
Answer:
The charge becomes positive.
Explanation:
When rubbed with cellulose acetate the charge of the fur/wool will become negative.
Why is 250 million years called a cosmic year?
That’s the amount of time it takes the Milky Way to revolve around the Universe core.
That’s the amount of time it takes the Milky Way to rotate on its axis.
That’s the amount of time it takes the solar system to rotate on its axis.
That’s the amount of time it takes the solar system to revolve around the Milky way core.
Answer:
250 million years is called a cosmic year because - D) That’s the amount of time it takes the solar system to revolve around the Milky way core.
Explanation:
The planets in our solar system orbit around the sun. ... Even at this blazing speed, it takes the sun approximately 225-250 million years to complete one journey around the galaxy's center. This amount of time – the time it takes us to orbit the center of the galaxy – is sometimes called a cosmic year.
The cosmic year is of 250 million years because that is the amount of time it takes in the solar system to revolve around the milky way core. Hence, option D is correct.
What is the Milky way?A large spiral galaxy known as the Milky Way contains the Sun and several hundred billion other stars. It gets its name from the Milky Way, an amorphous belt of stars and gas clouds that can be viewed in the sky from Earth. Astronomers do not fully comprehend the nature of the Milky Way Galaxy, which is commonly referred to simply as the Galaxy, despite the fact that Earth is located within it.
Much of the Galaxy is hidden by a thick layer of interstellar dust that prevents optical telescopes from seeing it, and astronomers can only determine its large-scale structure with the help of radio and infrared telescopes that can detect the types of radiation that can pass through the obscuring matter.
Our solar system's planets revolve around the sun. Even at this incredible speed, one orbit of the galaxy's center takes the sun about 225–250 million years to complete. A cosmic year is another name for the period of time it takes for us to orbit the galactic center.
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someone pls helpp meeee
Answer:
the first answer is correct
help me plzzz
The punter on a football team tries to kick a football so that it stays in the air for a long "hang
time". If the ball is kicked with an initial velocity of 30 m/s at an angle of 60 degrees above the
ground.
a. Calculate the "hang time".
b. How far does the ball go in the horizontal direction?
c. What is the maximum altitude (height) the ball reaches?
first resolve the initial velocity of the ball into two components
1)one parallel to ground(u)
2)another perpendicular to ground(v)
call the initial velocity=p=25.4 m/s at 58.0° deg to ground
so the horizontal component of velocity=25.4cos58=13.46 m/s
so the vertical component of velocity=25.4sin58=21.54 m/s
we have nothing to do with the horizontal component of velocity as it plays no part in the hang time
only vertical component of velocity determines the hang time
hang time=2*(vertical component of velocity)/(acceleration due to gravity)
==>hang time=2*21.54/9.8=4.39 s
==>hang time =4.39 s
If I'm wrong please let me know, thank you.
Ti3N + MgO → Mg3N2 +Ti2O balance chemical equation
We have that the balanced chemical equation is mathematically given as.
2Ti_3N + 3MgO → Mg_3N_2 +3Ti_2O
From the question we are told
Ti3N + MgO → Mg3N2 +Ti2O balance chemical equation.
Generally the way to balance an equation is by making all elements present on the Left hand side(LHS) same with the right hand side RHS.
Therefore
The equation is mathematically given as.
Ti_3N + MgO → Mg_3N_2 +Ti_2OWe consider the Left hand side(LHS) first.
2Ti_3N + 3MgO → Mg_3N_2 +Ti_2OThen we consider the right hand side RHS.
2Ti_3N + 3MgO → Mg_3N_2 +3Ti_2OTherefore the balanced chemical equation is mathematically given as.
2Ti_3N + 3MgO → Mg_3N_2 +3Ti_2OFor more information on this visit
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Help.. mee..
;-;
Dont answer if you dont know I dont want to fail this
Answer:
It would be B because the warm air heats up and then burns the marshmallow. And the heat and the marshmallow were touching each other
Explanation:
Answer:
its B because both objects are touching, every other option the heat moves through the air
Helllppppp pleaseeeeee!!!
A student practicing for a cross country meet runs 250 m in 30 s. What is the average speed
Answer:8.3m/sec 30 sec,
Explanation:
A student practicing for a track meet, ran 250 m in 30 sec. a. What was her average speed? 250 m = 8.3 m/sec 30 sec.
Please help meeeee!!!
Answer:
1. Test tube
2. tongs
3.
4. FUNNEL
5.
6.
7. Flask
8. Beaker
9. Bunsen burner
10. Erlenmeyer Flask
11. Molar and pestle
12. Wire gauze
13. Graduated cylinder
14. Test tube rack
15. Pipet
16. Filo
Explanation:
Which statement is true?
A. Speed is a scalar quantity and velocity is a vector quantity.
B. Speed and velocity are both scalar quantities.
C. Speed and velocity are both vector quantities.
D. Speed is a vector quantity and velocity is a scalar quantity.
E. Speed and velocity are neither a scalar quantity nor a vector quantity.
Help! Especially from any PLATO users!
A ) Speed is a scalar quantity and velocity is a vector quantity.
I WILL GIVE YOU THE BRAINLEST ANSWER AND 100 POINTS
Choose two of the following technological devices. For each one, complete the required research and write about how the devices use wave behavior to transmit or capture information.
Microwave
Radio
Remote control
WiFi
X-ray
Gamma radiation
Device 1
Describe the device and its function.
What form of electromagnetic radiation does it use?
Describe the frequency and wavelength range of this type of electromagnetic wave.
Using the information above and details from your research, write a paragraph of five sentences or more explaining how the device uses the behavior and characteristics of the electromagnetic wave to function. Remember the writing tips from the lesson, and use facts and details to explain your topic sentence.
You must include citations for all reliable sources used. Include citations from three or more reliable sources.
Device 2
Describe the device and its function.
What form of electromagnetic radiation does it use?
Describe the frequency and wavelength range of this type of electromagnetic wave.
Using the information above and details from your research, write a paragraph of five sentences or more explaining how the device uses the behavior and characteristics of the electromagnetic wave to function. Remember the writing tips from the lesson, and use facts and details to explain your topic sentence.
You must include citations for all reliable sources used. Include citations from three or more reliable sources.
The way a microwave uses wave behavior to transmit information is for point-point communication for small-sized antennas.
The form of electromagnetic radiation it uses is electrical and mechanical energy.
What is a Microwave?This refers to the form of electromagnetic radiation that has a range of 1m-1mm.
The way a radio uses wave behavior to transmit information is for wireless transmission of sound, typically for maritime and aircraft travel.
The form of electromagnetic radiation it uses is a radio wave.r
The range of the radio is 100–10 km at 3–30 kHz
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Answer:
.
Explanation:
Which kind of precipitation is formed, in part, by wind?
A. Rain
B. Snow
C. Sleet
D. Hail
Answer:
Rain
Explanation:
What is motivation in your own world
Answer:
Motivation is the process that initiates, guides, and maintains goal-oriented behaviors.
Weight of an object remains same on the Earth and the Moon.
true or false?
the density of free electron in a copper conductor is 8.5×10^28m-3. how long does an electron take to dift from one end of a wire 3.0m long to it's other end?
Answer:
missing information what is your cross-section and current in Amperes
WHY IS NO ONE HELPING I'M BOUTTA GET REPORTED FR!!!!!!!!!!!!!!
what would happen to the weather if half of the human race just died off? would it get colder? why?
Energy can be transformed from one form to another. The diagram shows one such process.
Which energy transformation is represented in the diagram?
nuclear to thermal and radiant
nuclear to electrical and chemical
chemical to nuclear and radiant
chemical to electrical and nuclear
Answer:
b
Explanation:
Answer
nuclear to electrical and chemical
Explanation:
Energy can be transformed from one form to another. The diagram shows one such process.
Which energy transformation is represented in the diagram?
nuclear to thermal and radiant
nuclear to electrical and chemical
chemical to nuclear and radiant
chemical to electrical and nuclear and it is ovisly b
Two skaters face one another and stand motionless, then push against each other on the ice. If one's mass is 55 kg and he moves to the left after the push at a velocity of 4.3 m/s, how fast was the other skater traveling after the push if her mass was 48 kg.
4.9 m/s to the right
Explanation:
We are going to use the conservation law of linear momentum to find her velocity. Initially, they are motionless so their initial total momentum is zero. Let's assume that anything moving to the left has a negative velocity and anything moving to the right has a positive velocity. We can write the conservation law of momentum as
[tex]0 = M_mv_m + M_wv_w[/tex]
where
[tex]M_m[/tex] = mass of the man = 55 kg
[tex]v_m[/tex] = velocity of the man = -4.3 m/s
[tex]M_m[/tex] = mass of the woman = 48 kg
[tex]v_w[/tex] = velocity of the woman
[tex]\Rightarrow 0 = (55\:\text{kg})(-4.3\:\text{m/s}) + (48\:\text{kg})v_w[/tex]
Solving for [tex]v_w,[/tex]
[tex]v_w = \left(\dfrac{55\:\text{kg}}{48\:\text{kg}}\right)(4.3\:\text{m/s}) = 4.9\:\text{m/s}[/tex]
going to the right.
40. What is the acceleration of a 10 kg object if a force of 3 N is applied to it?
If your hammer develops a loose head, you can tighten it by banging
it on the ground. A little physics secret though - it's better to bang
the hammer head up rather than head down. Explain, using inertia.
weight from the hammer head makes the inertia better making it better with the head up it. the body has less weight the inertia force isn't as good. (or something like that.)