Answer:
A ray of light traveling parallel to the principal axis of a concave mirror will be reflected out through the mirrors
Explanation: When a ray travelling parallel to the principle axis of a concave mirror then the light ray reflect out through the mirrors and passing through the focus.
Explanation:
Answer:
I hope this is the correct answer to your question, because ur question seems kinda wrong to me.
Explanation:
* when a ray of light traveling parallel to the principal axis of a concave mirror will be reflected out through the surface of the mirror and then passes through the focus .
The fielder attempts to catch a second ball. Just before the fielder catches the ball, the air resistance acting on the ball is 1.2N. Calculate the resultant force acting on the ball. Remember to include its direction and the unit. Assume the ball is falling vertically
Answer:
Resultant force = (1.2 - 9.8m)ĵ N
where m = mass of the ball
Magnitude of the resultant force = (9.8m - 1.2) N
Since the weight of the ball is expected to exceed the air resistance (because the ball is falling vertically downwards), the direction of the resultant force is vertically downwards. Its unit is Newtons, the SI unit of Force.
Explanation:
If a ball is falling vertically downwards, the only two forces acting on the ball include the weight of the ball (the pull of gravity on the ball) and the air resistance on the ball.
Weight of the ball acts downwards and is given as mg. where m = mass of the ball and g is the acceleration due to gravity = 9.8 m/s²
W = mg = (9.8m) N
In vector form, W = (-9.8mĵ) N
The air resistance on the ball = 1.2 N, the air resistance acts in the direction opposite the motion of the ball, and since the ball is moving vertically downwards, the air resistance acts vertically upwards.
In vector form, the air resistance = (1.2ĵ) N
Hence, the resultant force acting on the ball is the vector sum of all the forces acting on the ball.
Resultant force = (-9.8mĵ) + (1.2ĵ)
= (1.2 - 9.8m)ĵ N
Since the weight of the ball is expected to exceed the air resistance (because the ball is falling vertically downwards), the direction of the resultant force is vertically downwards.
Hope this Helps!!!
define hardware.Give 2 examples
Answer:
They are the physical parts of a computer.
examples :monitor,keyboard,system unit and mouse.
Need Help !
A 1500 kg car on flat ground is
moving 5.25 m/s. Its engine
creates a 1250 N forward force as the car moves 42.8 m. What is its final velocity?
Answer: 5.96m/s
Explanation:
Given the following :
Mass of car (m) = 1500kg
Velocity (V) = 5.25m/s
Forward force of engine = 1250N
Diatance moved = 4.8m
Final Velocity =?
Final kinetic energy = Initial kinetic energy + work done by engine
Initial kinetic energy = 0.5 × mass × velocity^2
Initial kinetic energy = 0.5 × 1500 × 5.25^2
Initial kinetic energy = 20671.875 J
Work done by engine = Force × distance
Work done by engine = 1250 × 4.8 = 6000J
Final kinetic energy = (20671.875 + 6000) J
= 26671.875 J
From kinetic energy = 0.5mv^2
26671.875 = 1/2 × 1500 × v^2
53343.75 = 1500v^2
v^2 = 35.5625
v = sqrt(35.5625)
v = 5.96m/s
A block of mass m is placed on a smooth wedge of inclination θ . The whole system is accelerated horizontally so that the block does not slip on the wedge. The force exerted by the wedge on the block has a magnitude: (A) mg tan θ (B) mg sin θ (C) mg cos θ (D) mg sec θ
Answer: mg/Cosθ
Explanation:
Taking horizontal acceleration of wedge as 'a'
FCosΘ = FsinΘ
F = mass(m) × acceleration(a) = ma
For horizontal resolution g = 0
Therefore,
Horizontal = Vertical
maCosΘ = mgSinΘ
aCosΘ = gSinΘ
a = gSinΘ/CosΘ
Recall from trigonometry :
SinΘ/Cosθ = tanΘ
Therefore,
a = gtanΘ
Normal force acing on the wedge:
mgCosΘ + maSinΘ - - - - (y)
Substitute a = gtanΘ into (y)
mgCosΘ + mgtanΘsinΘ
tanΘ = sinΘ/cosΘ
mgCosΘ + mgsinΘ/cosΘsinΘ
mgCosΘ + mgsin^2Θ/cosΘ
Factorizing
mg(Cosθ + sin^2Θ/cosΘ)
Taking the L. C. M
mg[(Cos^2θ + sin^2Θ) /Cosθ]
Recall: Cos^2θ + sin^2Θ = 1
mg[ 1 /Cosθ]
mg/Cosθ
Elements in the same periodic table group have the same___
Answer:
elements in the same periodic table group have the same valence electrons
A transformer has 500 turns of the primary winding and 10 turns of the secondary winding. a) Determine the secondary voltage if the secondary circuit is open and the primary voltage is 120 V
Answer:
First we use the fact that the ratio of the voltage on the secondary and on the primary will be the same as the ratio of the number of turns of both coils,
u=u^2/U^1 = N^2/N^1
we evaluate the unkown secondary voltage
u^ 2=N^2/N^1 u1
We substitute the given values -
u^2= 10/500 * 120v = 2.4v
Hence, the answer is 2.4v.
how wood helps in home insulation plz answer fast
plz answwweeeeeeerrrrrrr
Wood is a natural insulator due to air pockets within its cellular structure, which means that it is 15 times better than masonry, 400 times better than steel, and 1,770 times better than aluminum. In addition, lightweight wood framing methods allow easy installation of additional fibre or foil insulation. i hope this is better
when light passess from air into glass the angle of incidence is always _______ the angle of refraction
Explanation:
The angle of incidence is always smaller than the angle of refraction
A student has a 3v cell and the resistance in the circuit totals 6 ohms. How much current would flow in a series circuit?
Answer:
[tex]I=0.5 \:A[/tex] is the correct answer.
Explanation:
Using the ohm's law, we have:
[tex]V=IR\\\\I=\frac{V}{R}=\frac{3}{6}\\\\I=0.5 \:A[/tex]
Best Regards!
A radioactive isotope has a half-life of 2 hours. If a sample of the element contains 600,000 radioactive nuclei at 12 noon, how many radioactive nuclei would be left at 6 pm?
Answer: There will be 75258 nuclei left at 6 pm.
Explanation:
a) half-life of the radioactive substance:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.69}{k}[/tex]
[tex]k=\frac{0.69}{t_{\frac{1}{2}}}=\frac{0.693}{2hours}=0.346hours^{-1}[/tex]
b) Expression for rate law for first order kinetics is given by:
[tex]A=A_0e^{-kt}[/tex]
where,
k = rate constant
t = time for decomposition = 6 hours ( from 12 noon to 6 pm)
A = activity at time t = ?
[tex]A_0[/tex] = initial activity = 600, 000
[tex]A=600000\times e^{-0.346\times 6}[/tex]
[tex]A=75258[/tex]
Thus there will be 75258 nuclei left at 6 pm.
Most of the elements in the periodic table are___
Answer:
The most of the elements in the periodic table are metals. The elements cannot be gases and liquids (Molecules are mainly gases and liquids). Metalloids are few. Examples (Germanium, Arsenic)
An 18-kg bicycle carrying a 62-kg girl is traveling at a speed of 7 m/s. What is the kinetic energy of the girl
and bicycle combined together?
Answer:
1960 J
Explanation:
EK = (18 kg + 62 kg)[tex](7.0 m/s)^{2}[/tex]/2 = 1960 J
Newton’s first law of motion was a giant leap forward in scientific thought during Newton’s time. Even today, the idea is sometimes difficult at first for people to understand. Which statement is the best example of an object and motion that would make it hard for people to believe Newton’s first law? A rolling ball eventually slows down and comes to a stop. A wagon must be pushed before it begins to move. The heavier the load in a cart, the harder the cart is to turn. A box does not move when pushed equally from opposite sides.
Answer: A rolling ball eventually slows down and comes to a stop.
Explanation: Right on Edge2020, not C or B or D.
Answer:
A
Explanation:
Person above me might be right
I NEED HELP PLEASE, THANKS!
Identify each of the following as a conductors or insulators. Explain.
-cloth
-dry wood
-tap water
-glass
Answer:
Cloth:
It is an insulator since it can't let electricity pass through
Dry Wood:
It is an insulator and can't conduct electricity.
Tap Water:
It is a good conductor as it contains dissolved salts.
Glass:
It is an insulator since it can't let electricity pass through.
A boat travels at 15 m/s in a direction 45° east of north for an hour. The boat then turns and travels at 18 m/s in a direction 5° north of east for an hour.
What is the magnitude of the boat’s resultant velocity? Round your answer to the nearest whole number.
Answer:
16 m/s
Explanation:
First, find the displacement in the east direction.
x = (15 m/s sin 45°) (3600 s) + (18 m/s cos 5°) (3600 s)
x = 102,737 m
Next, find the displacement in the north direction.
y = (15 m/s cos 45°) (3600 s) + (18 m/s sin 5°) (3600 s)
y = 43,831 m
Find the magnitude of the displacement.
d = √(x² + y²)
d = √((102,737 m)² + (43,831 m)²)
d = 111,697 m
Finally, find the resultant velocity.
v = d / t
v = (111,697 m) / (7200 s)
v = 15.5 m/s
Rounded to the nearest whole number, the resultant velocity is 16 m/s.
a man has a mass of 70kg. Calculate his weight on earth where the gravitational strength is 10 N/kg
Answer:
So the weight of the body is 700N
Explanation:
mass of the object=70kg
force of gravity=10N/kg
weight of the object=w-?
as we know that
weight=mass × force of gravity
weight=70kg × 10N/kg
WEIGHT OF THE BODY=700N
I HOPE IT WILL HELP YOU
GOOD LUCK FOR THE ASSIGNMENT
The correct answer is 700 N.
Object mass = 70 kg
Gravity = 10N / kg
Weight = Mass x Gravity
Weight = 70kg x 10N / kg
Weight = 700 N
What is the gravity for a mass of 10kg?Mass is more basic because it is a unique property of the object. Weight varies from place to place depending on the acceleration of gravity. If the mass on the earth is m = 10kg, the weight is W = mg = 10 x 10 = 100N.
The strength of the Earth's gravitational field is 10 Newtons (N / kg) per kilogram. This means that there is a force of 10 Newtons per kilogram on Earth. Mass is the amount of substance that makes up an object.
Learn more about gravitational strength here: https://brainly.com/question/25624188
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11. What is the wavelength of an earthquake wave if it has a speed of 5000 m/s and a frequency of 10 HZ
step#1
step#2
step#3
Answer:
500 m
Explanation:
The applicable relation is ...
wavelength = speed/frequency
wavelength = (5000 m/s)/(10 cycles/s) = 500 m/cycle
The wavelength is 500 meters.
How much net force is required to keep a 3-kg object moving to the right with a constant speed of
6.0 m/s?
Answer:
Explanation:
Here,
m = 3 Kg
a = 0 m/s^2 (velocity is constant so the acceleration is zero)
We have,
F = ma
or, F = 3 x 0
or, F = 0 N
Constant velocity can always be associated with a zero net force.
Which condition must be met in order for an equation to be balanced?
Answer:
There must be an equal amount of each element on both sides of the equation. Hope this helps and please marks as the brainliest.
Explanation:
Answer:
The answer is D
Explanation:
Hope this helps!
A wave has a frequency of 450 Hz and a wavelength of 0.52 m. What is the speed of the wave?
Answer:
Explanation:
ave speed is always (frequency) x (wavelength)
Speed = (450 /sec) x (0.52 m)
= 234 m/sec .
which two elements define a story's setting?
geographical location
character description
weather conditions
plot structure
dialogue and action
Reset
Next
Answer:
Geographical location, and time and weather conditions
Answer:
Georgraphical location and weather conditions
Explanation:
Setting is where the story takes place so the location would be vital and same with weather conditions because it determines what the character(s) do
6 points + Brainliest asap!
If you double the amplitude of a box on a spring, how would that affect the acceleration at maximum displacement?
The acceleration would double.
The acceleration would remain the same.
The acceleration would triple.
The acceleration would be cut in 1/2.
Answer:
The acceleration would double
Explanation:
Assuming the same box and spring, the maximum acceleration is proportional to amplitude. When the amplitude doubles, the acceleration would double.
__
A spring is generally considered to have a linear force vs. distance characteristic. Hence, doubling the distance doubles the force. The acceleration is proportional to the force.
I NEED HELP PLEASE, THANKS! :)
A 20.0 cm tall object is placed 50.0 cm in front of a convex mirror with a radius of curvature of 34.0 cm. Where will the image be located, and how tall will it be? Please show all work.
Answer:
i = -12.7 cm; h = 5.07 cm
Explanation:
1. Find the focal length
The focal length of a concave spherical mirror is half of its radius of curvature.
f = ½r = ½ × 34.0 cm = 17.0 cm
2. Find the image distance
A convex mirror produces a virtual image behind the mirror, so the image distance is negative.
[tex]\begin{array}{rcl}\dfrac{1}{o} + \dfrac{1 }{i} & = & \dfrac{1}{f}\\\\\dfrac{1}{50.0} + \dfrac{1 }{i} & = & \dfrac{1}{-17.0}\\\\\dfrac{1}{i} & = & \dfrac{1}{-17.0} - \dfrac{1}{50.0}\\\\& = & \dfrac{50.0 - (-17.0)}{500\times(-17.0)}\\\\& = & \dfrac{67.0}{-850}\\\\i & = & \dfrac{-850}{67.0}\\\\& = & \textbf{-12.7 cm}\\\end{array}[/tex]
3. Find the image size
[tex]\begin{array}{rcl}\\\\\dfrac{h_{\text{i}}}{ h_{\text{o}}} & = & -\dfrac{i}{o} \\\\\dfrac{h_{\text{i}}}{ 20.0} & = & -\dfrac{-12.7}{50.0} \\\\h_{\text{i}} & = & 20.0 \times \dfrac{12.7}{50.0}\\\\& = & \textbf{5.07 cm}\\\end{array}[/tex]
Question: A swimmer has a swimming speed of 5.75 m/s in still water. When she
heads directly across the river, she ends up travelling downstream at an angle of 40°
(with respect to a line perpendicular to the shore).
(a) What is the speed of the current?
(b) What heading would the swimmer need to have in order to reach a point directly
across the river?
(c) If the river is 15 m wide, how long would a trip directly across the river take?
Answer:
(a) 4.82 m/s
(b) The simmer need to head 57.05° upstream of the river to reach a point directly opposite the river
(c) 4.024 seconds
Explanation:
The parameters given are;
The speed of the swimmer = 5.75 m/s
The direction of the resultant motion = 40° downstream
The speed of the current = x m/s
Therefore in a given second, we have that the swimmer moves 5.75 meters across the river while the current moves x meters downstream
Which gives;
[tex]tan(40^{\circ}) = \dfrac{x}{5.75}[/tex]
x = 5.75 × tan(40°) = 4.82 m/s
The speed of the current = 4.82 m/s
(b) If the swimmer swims at a direction θ to reach a point, p, directly opposite the river, we have;
The resultant speed across the river will be the swimmer's swimming speed which is 5.75 m/s
5.75² = y² + 4.82²
y = √(5.75² - 4.82²) = √9.78
tan(θ) = 4.82/(√9.78) = 1.54
θ = tan⁻¹(1.54) = 57.05°
The simmer need to swim 57.05° upstream to reach a point directly opposite the river
(c) If the river is 15 m wide, we have;
Time (t) = Distance/speed
The component of the swimmer's speed directly across the river = 5.75/(tan(57.05°)
The component of the swimmer's speed directly across the river = 3.73 m/s
The time, t, to cross the river is therefore;
t = 15/3.73 = 4.024 seconds
The estimated distance of the earth from the sun is 149000000km. The speed of the light is 300000km/s. What is the time taken for the light to travel from the sun to the earth
Answer:
The time taken for the light to travel from the earth to the sun = 496.67 seconds
Explanation:
Estimated distance of the earth to the sun = 149000000km
Speed of light = 300000km/s
Time taken for the light to travel from the sun to the earth = ?
Speed = Distance/time
time = Distance/speed
time = 149000000/300000
time = 496.67 s
The time taken for the light to travel from the earth to the sun = 496.67 seconds
I NEED HELP PLEASE, THANKS! :)
Radio waves can bend around buildings. An X-ray technician stands behind a wall during the use of her machine. What does this tell you about the relative wavelengths of these two types of invisible light?
Answer:
Radio waves have a wavelength between [tex]10^{-9}m[/tex] and [tex]10^{-12}m[/tex]
While,
X rays have a wavelength between 1m and 10km.
=> It is one of the condition of diffraction that the obstacle (coming in the way) must be comparable with the size of the wavelength.
=> This shows, that radio waves have a wavelength which is comparable with the size of buildings and can really easily diffract through it
=> While, X-rays are big enough to diffract through the wall.
So, if an X-ray technician stands behind a wall during the use of her machine, she will remain safe.
if a room is closed for 2-4 hours then when we open the door we need a little bit of more energy than the actual energy and feel someone is pushing the door from the back side . what is the reason behind it ? which force is that?
Answer:
The reason is because the pressure of the air inside the room drops with time which makes opening the door to require an increased amount of force to make up for the reduced pressure inside the room
Explanation:
From the kinetic theory of gases we have the following relation;
[tex]v_{rms} = \sqrt{\dfrac{3 \cdot K \cdot T}{m} }[/tex]
[tex]p = \dfrac{n \cdot MW \cdot v^2_{rms} }{3 \cdot V}[/tex]
Where:
K = Boltzmann constant
T = Temperature
m = Mass
MW = Molecular weight
V = Volume
[tex]v_{rms}[/tex] = Root mean square velocity
Whereby the room door is closed, the kinetic energy of the air particles will be used up such that the average velocity of the particles will decrease, given that the volume of the room is constant, the pressure inside the room will drop below the original pressure outside the room such that the force on the door due to the outside pressure is larger than the force on the door from inside the room requiring a larger amount of force to overcome the resistance of the now higher outside pressure force.
2. Fill in the blanks with appropriate words.
a. The force which acts towards the centre is called .......
force.
Answer:
centripetal force
Explanation:
because this force always compels the body to move in circle
Conductors and Insulators
Answer:
ConductorsThe substances which allow an electric current to pass through it is called conductors.
Example: Metals like copper,iron ,graphite etc.
InsulatorsThe substances which do not allow the electric current to pass through is called Insulators.
Example: Glass, dry wood ,plastic etc.
Hope this helps...
Good luck on your assignment...
Explain briefly the first aid measure that should be taken incase of poisoning
Answer:
How you treat someone who may have been poisoned depends on:
The person's symptoms
The person's age
Whether you know the type and amount of the substance that caused poisoning
If you are concerned about possible poisoning, call Poison Help at 800-222-1222 in the United States or your regional poison control center. Poison control centers are excellent resources for poisoning information and, in many situations, may advise that in-home observation is all that's needed.