Answer:
Omnidirectional antennas are inadvisable to be used because when oriented vertically they radiate radio power equally in all horizontal directions, but heir radio power varies with the angle to the axis, reducing to zero at the axis.
Explanation:
Omnidirectional antennas radiates equal radio power in all directions perpendicular to an axis, with power varying with the elevation angle. This means that their power declines to zero on the axis. This is unlike the isotropic antennas that radiates equal power in all directions, without any reduction in radio power with angle to the axis. Omnidirectional antennas are mostly used for radio broadcasting antennas in mobile devices that use radio such as cell phones, FM radios, walkie-talkies, wireless computer networks etc.
Calculate the de Broglie wavelength of a 4.5-MeV α particle. Explain if a relativistic or non-relativistic approach is required
Answer:
4.4x10^-32m
Explanation:
Using
Wavelength = hc/E
= 6.63*10^-34 * 3x10^8/ 4.5 x10^ 6ev
= 4.4*10^-32m
Yes a relativistic approach is used because the particle moves at the speed of light
What is 1.2 kg converted into mg.
I need to know for step by step please?
=> 1200 000 mg
ExPlaNatIoN :We know that,
1 kg = 1000 g
1 g = 1000 gm
then,
1.2kg = 1.2 × 1000 g = 1200 g
1200 g = 1200 × 1000 mg
=> 1200 000 mg1. An arrow is shot with an initial velocity of 60.0 m/s at an angle of 30.0° above the horizontal. What is the maximum height it will reach?
a. 23 m
b. 46 m
c. 69 m
d. 92 m
2. A projectile is launched horizontally from a cliff with an initial speed of 40 m/s. The cliff is 125 m high and the projectile travels a horizontal distance of 200 m from the bottom of the cliff. What is the speed of the projectile right before it hits the ground?
a. 48 m/s
b. 52 m/s
c. 56 m/s
d. 60 m/s
e. 64 m/s
Answer:
46m
Explanation:
Given the following :
Initial Velocity (u) = 60
Angle(θ) = 30°
Maximum height it will reach?
The maximum height if a projection is calculated using the formula :
H = u²sin²θ / 2g
Where H = maximum height, g = acceleration due to gravity = 9.8m/s²
H = (60²sin × 0. 5²) / 2(9.8)
H = 900 / 19.6
H = 45.918m
H = 46m
A hollow plastic sphere is held below the surface of a fresh-water lake by a cord anchored to the bottom of the lake. The sphere has a volume of 0.650 cubic meters and the tension in the cord is 900 N. a) Calculate the buoyant force exerted by the water on the sphere. b) what is the mass of the sphere? c) the cord breaks and the sphere rises to the surface. When the sphere comes to rest, what fraction of its volume will be submerged?
Answer: a) B = 6811N
b) m = 603.2kg
c) 86.8%
Explanation: Buoyant force is a force a fluid exerts on a submerged object.
It can be calculated as:
[tex]B=\rho_{fluid}.V_{obj}.g[/tex]
where:
[tex]\rho_{fluid}[/tex] is density of the fluid the object is in;
[tex]V_{obj}[/tex] is volume of the object;
g is acceleration due to gravity, is constant and equals 9.8m/s²
a) For the hollow plastic sphere, density of water is 1000kg/m³:
[tex]B=10^{3}.0.695.9.8[/tex]
B = 6811N
b) Anchored to the bottom, the forces acting on the sphere are Buoyant, Tension and Force due to gravity:
B = T + [tex]F_{g}[/tex]
B = T + mg
mg = B - T
[tex]m=\frac{B - T}{g}[/tex]
Calculating:
[tex]m=\frac{6811 - 900}{9.8}[/tex]
m = 603.2kg
c) When the shpere comes to rest on the surface of the water, there are only buoyant and gravity acting on it:
B = m.g
[tex]\rho_{w}.V_{sub}.g=m.g[/tex]
[tex]V_{sub}=\frac{m}{\rho_{w}}[/tex]
[tex]V_{sub}=\frac{603.2}{1000}[/tex]
[tex]V_{sub}[/tex] = 0.6032m³
Fraction of the submerged volume is:
[tex]\frac{V_{sub}}{V_{obj}}[/tex] = [tex]\frac{0.6932}{0.695}[/tex] = 0.868
What is the strength of electric field EpEp 0.60 mmmm from a proton? Express your answer to two significant figures and include the appropriate units.
Answer:
3.99*10^-3N/C
Explanation:
Using
Ep= kq/r²
Where r = 0.6mm = 0.6*10^-3m
K= 8.9*10^9 and q= 1.6*10^-19
So = 8.9*10^9 * 1.6*10^-19/0.6*10^-3)²
= 3.99*10^-3N/C
A scientific LAW has been proven and a THEORY has not. True Or False
Answer:
true
Explanation:
i did the test its right
Answer:
true
mark mine as brainiest, i could use the points
A dog runs 300m North and sees the dog catcher and runs 120 m south .Whats the dogs displacement.The same jogger runs 3 miles around the track, starting and finishing in the same time after completing exactly 12 laps. What is the average velocity now
Answer:
1. 180 m
2. 1.5 miles/hour
3. 0 m/s
Explanation:
The complete question is
A dog runs 300 m North and sees the dog catcher and runs 120 m south Whats the dogs displacement.
A jogger runs north for 3.0 miles. If this took 2.0 hours, what is the jogger’s average velocity in miles per hour?
The same jogger runs 3.0 miles on the track, starting and finishing his run after completing exactly 12 laps around the track. What is his average velocity?
1. Displacement is how far the dog moves from the original starting point.
If the dog runs 300 m north, and then 120 m south, then the displacement from the starting point will be
displacement = 300 - 120 = 180 m
2. Displacement of the jogger = 3 miles
Time taken by the jogger = 2 hours
velocity of the jogger = ?
Velocity is = displacement/time
velocity = 3/2 = 1.5 miles/hour
3. velocity = displacement/time
if the jogger completes exactly 12 laps around the track, then the jogger will return to the starting point. This means that the jogger's displacement from the starting point is 0 miles
Jogger's velocity will therefore be = 0 m/s
Convert 300 K into the celsius scale
Convert 220 °C into kelvin scale.
Convert 30 °C into fahrenheit scale
Convert 260 °F into °C.
Answer:
26.85 Celsius.
493.15 Kelvin
86F
26.85
493.15
Tk=Tc+273.15
The atmospheric pressure at normal conditions is equal to 10.33 m under water. Then 1.0mm mercury equals to
mm water.
Answer:13.6
Explanation:
In a walking investigation, Josephine
walked a total distance of 40 feet. At the
halfway point, she had walked for 25
seconds. She stopped for 5 seconds to tie
her shoe and then continued for 25 more
seconds. Sketch a graph that shows
Josephine's distance from the starting point
over time
Explanation:
She walked 20 feet in the first 25 seconds. Then she stayed at the 20 foot position for 5 seconds. Then she walked another 20 feet in 25 seconds. See attached graph.
the unit for the measure of distance is
Answer: Well their are many Miles, inches, kilometres, meters, cementers, and so on.
hope it helps you bye
Centimetre, Meter, & Kilometre
Two point charges are separated by a certain distance. How does the strength of the electric field produced by the first charge, at the position of the second charge, change if the second charge is doubled?
Answer:
The field will remain the same
Explanation:
This is because electric field given as
E1= kq1/r²
And that of second charge
E² = kq2/r²
Is not affected by the size of the second charge q2
3. Which statement best describes the research projects that are funded by private
foundations?
a. Research projects that have little chance of success
b. Research projects for a specific cause
c. Research projects concerning the environment
d. Research projects that benefit consumers
Answer:
b. Research projects for a specific cause
Explanation:
Research funded by private foundations are usually for a specific cause. These type of research are usually properly scrutinized, and must have a high probability of success. Most of these projects may not be to benefit the consumers, but are usually done with a special purpose in mind.
A runner changing speed from 3 meters per second to 5 meters per second is an example of
Answer: acceleration
Explanation:
he is accelarting from 3 meters per second to 5 meters per second
Answer:
acceleration
Explanation:
Determine the acceleration (in m/s) of an object which
A. changes its velocity from 12.1 m/s to 23.5 m/s in 7.81 seconds
B. accelerates from 33.4 m/s to 18.9 m/s over a distance of 109 m
C. accelerates from 21.5 m/s to 8.9 m/s over a distance of 109 m
Please help!
Explanation:
A=23.5-12.1/7.81
1.46
b)(18.9^2-(33.4)^2)/2(109)
-3.5
c)8.9^2-(21.5)^2/2(109)
-1.76
Which of the following is true of the structures labeled A in the cell membrane?
Choose 1 answer:
(Choice A) A They are membrane proteins.
(Choice B) B They are entirely hydrophobic.
(Choice C) C They are phospholipids.
(Choice D) D They are carbohydrates. Report a problem
Answer:
they are membrane proteins
A body is projected vertically upwards with a velocity of 10m/s from a vertically upward position at height h another body is dropped down at the same instant
Answer:
0.25 second
Explanation:
Given :
Velocity, v = 10 m/s
The height,
[tex]$ h = \frac{v^2}{2g} $[/tex]
[tex]$ h = \frac{10^2}{2\times 9.8} $[/tex]
= 5 m
Therefore the time at which both the bodies meet is
[tex]$ t = \frac{h}{v+v} $[/tex]
[tex]$ t = \frac{5}{10+10} $[/tex]
[tex]$ t = \frac{5}{20} = 0.25$[/tex]
So, time taken is 0.25 seconds
please anyone help me to answer this questions.plzz... it's very urgent..
Answer:
1) 3 applications of pressure in daily life are :-
● The area of sharp edge of knife, scissor or handsaws are much less then blunt edge. So, for same total force pressure is more for sharp edges than the blunt one. Hence sharp knife, scissors etc, cuts easily than a blunt one.
●Broad handles in bags and suitcases are provided for the comfort. Broad handles have large area. So, the pressure exerted on hands and shoulders would be small while carrying the bags and the suitcases.
●Trucks carrying heavy loads have more than four tyres. More tyres in case of trucks increase the area of contact with the road. This results in reduced pressure on the tyres.
2) Area of the surface which is on ground = 1.5×1
= 1.5m^2
Mass of the block = 300kg
Force applied by the block = Mass × g = 300×10
= 3000N (where g = acceleration due to gravity )
Pressure = Force applied / Area of the surface
= 3000N / 1.5m^2
= 2000 Pa
3)
a) The above experiment signifies that more the area of the surface of an object , less the pressure an object applies.
b) B exerts the minimum pressure because the area of its surface to ground is greater than others & as it has more area of surface , it exerts less pressure. ( area is inversely proportional to pressure )
c) D exerts the maximum pressure because the area of its surface to ground is lesser than others & as it has less area of surface , it exerts more pressure. ( area is inversely proportional to pressure )
d) It depend upon the way an object is kept on ground. If an object is kept in such a way dat the area of the surface to the ground is more , then pressure will be least exerted .If an object is kept in such a way dat the area of the surface to the ground is less, then pressure will be exerted more .
e) Do it yourself . only i will suggest that make the tip of the cone ( which is to the ground ) more narrower.
Explanation:
Select the correct equations that show that a freely falling rock drops a distance of 80 m when it falls from rest for 4 s .
Answer:
1 and 4
Explanation:
How does online gaming affect the health of the student
Answer:
because we more see th online gaming and not eat food and playing that game all the time so it effect the health
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Why is there no ideal time of day when all students should study?
Answer:because each individual works best at a different time of day. D. because scheduling prevents everyone from studying at a set time. emilleexo818 is waiting for your help.
Explanation:
Answer:
The correct and overall question would be: Because each individual works best at a different time of day
Explanation:
(I'm smart and I took the quiz, I hope this helped guys! :)
Within the nebula that was the start of our solar system, a shock wave from an exploding supernova triggered dust particles to be drawn together to form a dense spherical cloud. The accumulation of dust set off a chain reaction. As the core of the cloud attracted more dust, its gravitational pull increased. As this pull increased so did all BUT its
Answer:
B expansion
Explanation:
In a cloud of gas and dust known as the solar nebula, the Sun and the planets jointly created 4.6 billion years ago. The solar nebula presumably collapsed as a result of a shock wave from a nearby supernova explosion. Thus, option A is correct.
What nebula that was the start of our solar system?A nearby supernova explosion's shock wave is most likely what caused the solar nebula to collapse.The planets formed in a thin disk around the Sun, which formed in the centre of the solar system. Moons began to form similarly around the gas giant planets.
Every speck of stuff in the solar system was once a massive nebula, or floating interstellar cloud, before it was shaped into a tidy collection of planets.
Therefore, a shock wave from an exploding supernova triggered dust particles to be drawn together to form a dense spherical cloud.
Learn more about nebula here:
https://brainly.com/question/9497068
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What is the acceleration of softball if it has a mass of 5 kg and hits the catchers glove with a force of 35 N
Answer:
50m/s2^
Explanation:
We know , by newton's law of motion .
F=ma
a=f/m
a=25/0.5
a=50m/s2^
Therefore , the acceleration of a softball is .
Answer:
7 m/s²
Explanation: Force = Mass x acceleration
Also note that 1 N = 1 kg.m/s²
a=F/ m
a= 35 N/ 5 kg = 35 kg.m/ s² ÷ kg Aside:( so you cross out the kg)
a= 7 m/s²
A ball is thrown upward from an initial height of 1.5m the ball reaches a height of 5m then falls to the ground . What Is the distance traveled by the ball? What is the displacement of the ball?
Answer:
8.5m and 3.5mExplanation:
In this problem, we are expected to solve/find the total distance traveled and also the displacement of the ball.
given that the initial height is 1.5m and was thrown to a height of 5m
the total distance covered when the ball falls to the ground
Note (see attached a rough sketch for the pictorial explanation)
1. The distance for A to B= 3.5 m
2. The distance from B to A= 3.5 m
3. The distance fro A to C= 1.5 m
the total distance is 3.5+3.5+1.5= 8.5m
the displacement is simply the difference between the final position and the initial position
displacent= 5-1.5= 3.5m
I NEED THIS IN AN HOUR! PLEASE PLEASE PLEASE HELP Tim and Jim measured the length of the same piece of board. Using a certain ruler, Tim obtained a length of 0.96 centimeter. Using a different ruler, Jim obtained a length of 0.9662 centimeter. Which measurement is better? Explain the reason for your answer.
Answer:
Jims is better
Explanation:
His number is more complex which means it is more accurate
Two trains traveling towards one another on a straight track are 300m apart when the engineers on both trains become aware of the impending Collision and hit their brakes. The eastbound train, initially moving at 97.0 km/h Slows down at 3.50ms^2. The westbound train, initially moving at 127 km/h slows down at 4.20 m/s^2. What is the distance between them once they stop (express your answer to the two significant figures)
Answer:
48 m
Explanation:
Two trains traveling towards one another on a straight track are 300m apart when the engineers on both trains become aware of the impending Collision and hit their brakes. The eastbound train, initially moving at 97.0 km/h Slows down at 3.50ms^2. The westbound train, initially moving at 127 km/h slows down at 4.20 m/s^2.
The eastbound train
First convert km/h to m/s
(97 × 1000)/3600
97000/3600
26.944444 m/s
As the train is decelerating, final velocity V = 0 and acceleration a will be negative. Using third equation of motion
V^2 = U^2 - 2as
O = 26.944^2 - 2 × 3.5 S
726 = 7S
S = 726/7
S1 = 103.7 m
The westbound train
Convert km/h to m/s
(127×1000)/3600
127000/3600
35.2778 m/s
Using third equation of motion
V^2 = U^2 - 2as
0 = 35.2778^2 - 2 × 4.2 × S
1244.52 = 8.4S
S = 1244.52/8.4
S2 = 148.2 m
S1 + S2 = 103.7 + 148.2 = 251.86
The distance between them once they stop will be
300 - 251.86 = 48.14 m
Therefore, the distance between them once they stop is 48 metres approximately.
A car slows down uniformly from a speed of 22 m/s to rest in 4.0 seconds. How far did it travel in that time
Answer:
[tex] \boxed{\sf Distance \ travelled = 44 \ m} [/tex]
Given:
Initial speed (u) = 22 m/s
Final speed (v) = 0 m/s (Rest)
Time taken (t) = 4 seconds
To Find:
Distance travelled by car (s)
Explanation:
From equation of motion of object moving with uniform acceleration in straight line we have:
[tex] \boxed{ \bold{s = (\frac{v + u}{2} )t}}[/tex]
By substituting value of v, u & t in the equation we get:
[tex] \sf \implies s = ( \frac{0 + 22}{2} ) \times 4 \\ \\ \sf \implies s = \frac{22}{2} \times 4 \\ \\ \sf \implies s = 11 \times 4 \\ \\ \sf \implies s = 44 \: m[/tex]
[tex] \therefore[/tex]
Distance travelled by car (s) = 44 m
Determine the mass of the object below to the correct degree of precision.
272.83 g
272.9 g
272.90 g
272.94 g
Answer : The correct degree of precision is 272.94 g.
Explanation :
Precision : It is defined as the closeness of two or more measurements to each other.
For Example: If you weigh a given substance five times and you get 2.7 kg each time. Then the measurement is said to be precise.
Level of precision is determined by the maximum number of decimal places.
In the given figure, the value of mass of object is 280 g. From the given options we conclude that the 272.94 g is more close to 280 g and has maximum number of decimal places. So, 272.94 g measurement is said to be precise.
Therefore, the correct degree of precision is 272.94 g.
Q1: A runner is jogging in a straight line at a steady vr= 6.8 km/hr. When the runner is L= 2.4 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 13.6 km/hr (2 times as fast as the runner). When the bird reaches the finish line, it turns around and flies directly back to the runner. What cumulative distance does the bird travel? Even though the bird is a dodo, assume that it occupies only one point in space (a “zero” length bird), travels in a straight line, and that it can turn without loss of speed. Answer in units of km. Q2: After this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. The bird repeats the back and forth trips until the runner reaches the finish line. How far does the bird travel from the beginning (including the distance traveled to the first encounter)? Answer in units of km.
Answer:
Q1: 3.2km
Q2: 4.8K
Explanation:
Q1:
So db is the distance of bird, and dr is the distance of runner
db = 2vr and the distance of bird is going to be 2 times greater than the runner.
formulas: db = 2vr & db = 2dr
db = 2drL + (L - x) = 2x2L - x = 2x2L = 3xx = [tex]\frac{2}{3}[/tex]LInsert it in x = [tex]\frac{2}{3}[/tex]L
[tex]\frac{2}{3}[/tex](2.4km) = 1.6km
Now we use formula db = 2dr
db = 2L - xdb = 2(2.4km) - 1.6kmdb = 3.2kmQ2:
Formulas: Vr = L /Δt & Vb = db/Δt
Vr = L/ Δt ⇒ Δt = [tex]\frac{L}{Vr}[/tex][tex]\frac{2.4km}{6.8km/hr}[/tex][tex]\frac{6}{17}hr[/tex](Km cancel each other)
Vb = db/Δt ⇒ db = VbΔt13.6km/hr[tex](\frac{6}{17}hr )[/tex]4.8km(hr cancel each other)
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A carpenter apprentice was killed when he was struck in the head by a nail that was fired from a powder actuated tool. The tool operator, while attempting to anchor a plywood form in preparation for pouring a concrete wall, fired the gun, causing the nail to pass through the hollow wall. The nail traveled some twenty-seven feet before striking the victim. The tool operator had never received training in the proper use of the tool, and none of the employees in the area were wearing personal protective equipment. What should be recommended to prevent this accident from happening again?
Answer:
Explanation:
The recommendations that need to be urgently addressed by the workshop and it's employees are
1) Training of all employees (particularly the tool operators) on the safe and proper use of all tools used in the course of the carpentry work.
2) Training of all employees in health, safety and environment (HSE). This training will help them appreciate the importance of always wearing personal protective equipment (PPE) when at the workshop or during the course of a work (because if the apprentice was putting on an engineer's helmet, he could have been safe).
3) Employees who fail to adhere strictly to the use of PPE should be sanctioned or even dismissed from the workplace