Answer: A
Explanation: When a steel ball is thrown into a viscous liquid, three forces will act on the ball.
1.) The viscous drag force V which is acting upward
2.) The buoyant force U which is acting upward and
3.) The weight of the ball W. Which is acting downward.
When it is moving with an acceleration a, the weight W will be greater than U and V
Since Force = ma.
The resultant vector force will be
W - V - U = ma
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 space shuttle travels in orbit at 21,000 km/hr. how far will it travel in 5 hr
Answer:
Explanation:
distance = speed * time
distance = 21000 * 5 = 105000 km
please mark me as Brainliest
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
Which metal is used in thermometers?
Answer:
Mercury
Explanation:
Depends on the kind of thermometer.
But traditionally, Mercury has been used in "Liquid-In-Glass" Thermometers
Answer:
Mercury
Explanation:
Most metals are good conductors of heat and they are solids at room temperature. Mercury is the only one in liquid state at room temperature. It's used in thermometers because it has high coefficient of expansion.
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
Un bombero alejado d = 31.0 m de un edificio en llamas dirige un chorro de agua desde una manguera contra incendios a nivel del suelo con un ángulo de θi = 33.0° arriba de la horizontal como se muestra en la figura siguiente. Si la rapidez del chorro cuando sale de la manguera es vi = 40.0 m/s, ¿a qué altura (en m) golpeará el edificio? m
Answer:
El chorro golpea el edificio a una altura de 15.943 metros con respecto al suelo.
Explanation:
El chorro de agua exhibe un movimiento parabólico, dado que este tiene una inclinación inicial y la única aceleración es debida a la gravitación terrestre. Las ecuaciones cinemáticas que modelan el fenómeno son:
Distancia horizontal (en metros)
[tex]x = x_{o} + v_{o}\cdot t \cdot \cos \theta[/tex]
Donde:
[tex]x_{o}[/tex] - Posición horizontal inicial, medida en metros.
[tex]t[/tex] - Tiempo, medido en segundos.
[tex]v_{o}[/tex] - Velocidad inicial, medida en metros por segundo.
[tex]\theta[/tex] - Angulo de inclinación del chorro de agua, medido en grados sexagesimales.
Distancia vertical (en metros)
[tex]y = y_{o} + v_{o}\cdot t \cdot \sin \theta + \frac{1}{2}\cdot g \cdot t^{2}[/tex]
Donde:
[tex]y_{o}[/tex] - Posición vertical inicial, medida en metros.
[tex]g[/tex] - Constante gravitacional, medida en metros por segundo al cuadrado.
Partiendo de la primera ecuación, se despeja el tiempo:
[tex]t = \frac{x - x_{o}}{v_{o}\cdot \cos \theta}[/tex]
Si [tex]x = 31\,m[/tex], [tex]x_{o} = 0\,m[/tex], [tex]v_{o} = 40\,\frac{m}{s}[/tex] and [tex]\theta = 33^{\circ}[/tex], entonces:
[tex]t = \frac{31\,m-0\,m}{\left(40\,\frac{m}{s} \right)\cdot \cos 33^{\circ}}[/tex]
[tex]t = 0.924\,s[/tex]
La altura máxima se calcula por sustitución directa de términos en la segunda ecuación. Si [tex]y_{o} = 0\,m[/tex], [tex]v_{o} = 40\,\frac{m}{s}[/tex], [tex]t = 0.924\,s[/tex] y [tex]g = -9.807\,\frac{m}{s^{2}}[/tex], entonces:
[tex]y = 0\,m + \left(40\,\frac{m}{s} \right)\cdot (0.924\,s)\cdot \sin 33^{\circ} + \frac{1}{2}\cdot \left(-9.807\,\frac{m}{s^{2}} \right) \cdot (0.924\,s)^{2}[/tex]
[tex]y = 15.943\,m[/tex]
El chorro golpea el edificio a una altura de 15.943 metros con respecto al suelo.
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.
Elements in the same periodic table group have the same___
Answer:
elements in the same periodic table group have the same valence electrons
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.
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
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
Part B
What were the reactants of the first experiment in the video?
1
х,
Font Sizes
A -
A
: EEE
Answer:
zinc and hydrochloric acid
Explanation:
Answer:
The reactants he used in the first experiment were zinc metal and hydrochloric acid.
Explanation:
edmentum
what are the fundamental units used in physics?
Answer:
Metre, kilogram, second, ampere, kelvin, candela, and mole
Explanation:
A base unit (also referred to as a fundamental unit) is a unit adopted for measurement of a base quantity
I NEED HELP PLEASE, THANKS! :)
Explain how the diffraction of light shows that light behaves like a wave.
Answer:
Diffraction of light shows that light behaves like a wave. It involves the change in the direction of waves while passing through any obstacle. Diffracted light can produce fringes of light, dark or colored bands (Just like the rainbow which is also a light wave). Diffracted light has certain wavelength, amplitude , frequency and speed which are the basic characteristics of being a wave which shows that light actually behaves like a wave.
A person, with a mass of 50.0 kg, stands on a weighing scale in a lift which is moving
upwards with a uniform acceleration of 5.0 m/s
2
. What would be the reading on the
scale?
(A) 490 N (B) 250 N (C) 740 N (D) 240 N
Answer:
D
Explanation:
Because I just had that answer
I NEED HELP PLEASE THANKS :)
Explain how the diffraction of light shows that light behaves like a wave.
Explanation:
Diffraction of light involves a change in direction of waves as they pass through an opening or around an obstacle in their path. Water waves have the ability to travel around corners, around obstacles and through openings.
Look at figure D . Explain what will happen if a larger mass it put on the force meter
it will experience great force
To break a chemical bond, particles need to collide with a certain amount of a]energy. b]atoms. c]molecules. d]chemicals.
Answer:
Energy
Explanation:
The stronger the force it has the more quickly the bonds will break
As there will be more energy they will vibrate more and the bonds will separate easily..
Physics students study a piano being pulled across a room on a rug. They know that when it is at rest, it experiences a gravitational force of 2200 N. When it is being pulled with 1200 N it is sliding across the room in equilibrium, but the students feel like they had to pull harder than 1200 N at first to begin motion.
Answer:
4
Explanation:
hope this helps
Answer:
The static frictional force is greater than the kinetic frictional force, so the static frictional force is greater than 1200 N.
Explanation:
Edge 2021
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
A car is running with a velocity of 29 m/s.How far does is it go in 2 minute?
Answer:
Distance = 3480m/s²
Explanation:
[tex]d = vt \\ v = 29 \\ t = 2 \: min= 120 seconds \\ d = 29 \times 120 \\ d = 3480[/tex]
speed = distance ÷ time
29=distance ×2
2×29= distance
58= distance
so,
distance is 58 meters
The energy from 0.015 moles of octane was used to heat 250 grams of water. The temperature of the water rose from 293.0 K to 371.2 K. What is the enthalpy of combustion of octane? The specific heat capacity of water is 4.18 J/K g.
A. -1226 kJ/mol
B. -5448 kJ/mol
C. 293.25 kJ/mol
D. 1226 kJ/mol
Answer : The correct option is, (B) -5448 kJ/mol
Explanation :
First we have to calculate the heat required by water.
[tex]q=m\times c\times (T_2-T_1)[/tex]
where,
q = heat required by water = ?
m = mass of water = 250 g
c = specific heat capacity of water = [tex]4.18J/g.K[/tex]
[tex]T_1[/tex] = initial temperature of water = 293.0 K
[tex]T_2[/tex] = final temperature of water = 371.2 K
Now put all the given values in the above formula, we get:
[tex]q=250g\times 4.18J/g.K\times (371.2-293.0)K[/tex]
[tex]q=81719J[/tex]
Now we have to calculate the enthalpy of combustion of octane.
[tex]\Delta H=\frac{q}{n}[/tex]
where,
[tex]\Delta H[/tex] = enthalpy of combustion of octane = ?
q = heat released = -81719 J
n = moles of octane = 0.015 moles
Now put all the given values in the above formula, we get:
[tex]\Delta H=\frac{-81719J}{0.015mole}[/tex]
[tex]\Delta H=-5447933.333J/mol=-5447.9kJ/mol\approx -5448kJ/mol[/tex]
Therefore, the enthalpy of combustion of octane is -5448 kJ/mol.
Answer:
B.) -5448 kJ/mol
Explanation:
I got it correct on founders edtell
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.
What is the advantage of using multiple cylinders in an engine?
Answer:
Temperature stresses are reduced as the multi-cylinder engine has more cooling surface area due to smaller cylinder bore. The intensity of vibration is sufficiently reduced as the primary and secondary forces are balanced. More power strokes per revolution giving smooth torque output.
Explanation:
The table shows data for the planet Uranus.
A 2 column table with 4 rows. The first column is labeled Quantity with entries, Escape velocity in kilometers per second, Gravitational acceleration in meters per second squared, Orbital velocity in kilometers per second, Length of day in hours. The second column is labeled Value with entries, 21.3, 8.7, 6.8, 17.2.
To the nearest whole number, how much would a 25.0 kg rock weigh on Uranus?
170 N | 218 N | 430 N | 532 N
Answer:
218 N
Explanation:
The weight of the object on Uranus W = mg' where m = mass of the object = 25.0 kg and g' = gravitational acceleration.
Since in the table, we are given different values, we look for the value of the gravitational acceleration because, that is the only variable there that can help us calculate the weight of the object.
From the table, the gravitational acceleration g' = 8.7 m/s².
So, the weight of the object W = mg'
= 25.0 kg × 8.7 m/s²
= 217.5 N
≅ 218 N
Answer:
B. 218 N
Explanation:
Edge 2020
Supriya has a pre-paid electricity connection at home. On a sultry Sunday afternoon, she checks that she only has ₹9 left in the balance. She wants to use the air conditioner (AC), rated at 1.2 kW. The price of electricity is ₹10 /unit in her area. How long can she run the AC before her balance is over and the power runs out?
Answer: 0.75 hour(s) or 45 minutes
Explanation:
1 unit of electricity = 1kwh
Amount of energy consumed by 1kw load in one hour
Price per unit = ₹10
Air conditioner rating(power) = 1.2Kw
Given that balance = ₹9
Therefore, supriya's total energy cost = energy balance = ₹9
Total energy cost = power in kilowatt × time of operation (in hour) × cost per unit
₹9 = 1.2kw × time × ₹10
₹9 = 12 × time
Time = 9 / 12
Time = 0.75 hours
0.75 × 60 = 45 minutes
1) Which one of the following is vector,
B) Momentum
C) Mass
A) Energy
D) Temperature
Answer:
momentum is a vector quantity that points in the same direction as velocity
Explanation:
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.
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
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.