A person standing on a building ledge throws a ball vertically from a launch position 55 m above the ground. It takes 2.0 s for the ball to hit the ground.
With what initial speed was the ball thrown?
Answer:
Vo = 17.69 [m/s]
Explanation:
To solve this problem we must use two equations of kinematics.
[tex]v_{f}^{2} =v_{o}^{2} +2*g*h\\v_{f}=v_{o}+g*t[/tex]
where:
Vf = final velocity [m/s]
Vo = initial velocity [m/s]
g = gravity acceleration = 9.81 [m/s²]
h = elevation = 55 [m]
t = time = 2 [s]
Now we replace the gravity acceleration into the second equation:
[tex]v_{f}=v_{o}+9.81*2\\v_{f}=v_{o}+19.62[/tex]
And then into the first equation:
[tex](v_{o}+19.62)^{2}=v_{o}^{2}+2*9.81*55\\v_{o} ^{2}+2*v_{o}*19.62+384.94=v_{o}^{2} + 1079.1\\39.24*v_{0}=694.16\\v_{o}=17.69[m/s][/tex]
The initial speed at which the ball is thrown upward is 17.7 m/s.
According to the question the initial position of the ball, y = 55 m, and the final position of the ball is y' = 0 m. We have assumed upward direction as positive direction and downward as negative direction.
so the total displacement:
d = y'-y = 0 - 55
d = -55 m
now applying the second equation of motion:
d = ut - (1/2)gt²
where t = 2s ( given ) and g = 9.8 m/s².
-55 = 2u - 0.5×9.8×4
-55 = 2u - 19.6
u = -17.7 m/s
the negative sign indicated that the initial velocity is opposite to the direction of displacement.
This means the initial velocity is upward as it should be.
Therefore, the initial speed of the ball is 17.7m/s
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Two children are riding on a rotating merry-go-round. Child A is at a greater distance from the axis of rotation than child B. Which child has the larger tangential speed?
Answer:
Child A.
Explanation:
For all points on the merry-go-round, the angular speed ω is the same, as it's the rate of change of the angle rotated regarding time, and all points along the same radius rotate at the same time.Based on the definition of angular velocity, and the definition of angle, we find that there exists a fixed relationship between the angular speed and the tangential speed, as follows:[tex]v_{t} = \omega * r (1)[/tex]
So, since ω remains constant, the tangential speed is directly proportional to the distance from the axis of rotation r.This means that it will be larger for the child A, who is at a greater distance from the axis of rotation than child B.what is the mass of a chair that weights 118 Newton’s
Answer: 6899
Explanation:
The mass of a chair that weighs 118 Newtons is 12.04kg
HOW TO CALCULATE MASS:
The mass of a substance can be calculated by dividing the weight of the substance by its acceleration due to gravity as follows:Mass = weight ÷ accelerationAccording to this question, the mass of a chair weighs 118 Newtons. It can be calculated as follows:Mass = 118N ÷ 9.8m/s²Mass = 12.04kgTherefore, the mass of a chair that weighs 118 Newtons is 12.04kg.Learn more at: https://brainly.com/question/8164654?referrer=searchResults&source=aidnull
4. What is the mass of the block
of iron illustrated below?
Ty in advance
What can be said about all atoms in an element
Answer:
All atoms have a dense central core called the atomic nucleus. Forming the nucleus are two kinds of particles: protons, which have a positive electrical charge, and neutrons, which have no charge. All atoms have at least one proton in their core, and the number of protons determines which kind of element an atom is.
Explanation:
What are two ways electromagnetic waves are used in a home computer scanner?
A.
An image is produced when a silicon chip releases electrons by the photoelectric effect.
B.
Visible light is reflected off an object and then captured by a charge-coupled device.
C.
X-rays shine on objects, and the rays either pass through or are absorbed by the objects.
D.
Red light shines on a black-and-white object, and light is reflected according to the pattern of black and white.
Two ways electromagnetic waves are used in a home computer scanner are:
An image is produced when a silicon chip releases electrons by the photoelectric effect.Visible light is reflected off an object and then captured by a charge-coupled device.What is electromagnetic wave?In terms of science, electromagnetic radiation (EMR) is made up of electromagnetic (EM) field waves that travel over space while carrying electromagnetic radiant energy. It consists of X-rays, gamma rays, microwaves, infrared, visible light, ultraviolet, and radio waves. These waves are all a component of the electromagnetic spectrum.
Electromagnetic waves, which are synchronised oscillations of the electric and magnetic fields, are the traditional form of electromagnetic radiation. The electromagnetic spectrum is created at various wavelengths depending on the oscillation frequency. Electromagnetic waves move at the speed of light in a vacuum.
Hence, option (A) and (B) are correct.
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6.
A runner completed the 100.-meter dash in
10.0 seconds. Her average speed was
A) 10.0 m/s
B) 1,000 m/s
C) 0.100 m/s
D) 100 m/s
Answer:
A) 10.0 m/s
Explanation:
the formula for average speed is v=d/t
the distance is 100 meters
The time is 10.0 seconds
so v=100m/10.0s
= 10.0m/s
so the runners average speed was 10.0m/s
The average speed of the runner is equal to 10.0 m/s. Therefore, option (A) is correct.
What is speed?The speed of a body can be described as the distance covered in a definite time interval. The average speed can be defined as a scalar parameter as it possesses magnitude with no direction.
The speed can be determined from the ratio of the distance traveled by the object to the time taken to travel that distance.
The speed of any object can be calculated from the formula equation mentioned below:
Speed = total distance /time taken
Given, the distance covered by the runner = 100 m
The time taken by the runner, t = 10.0 s
The average speed of the runner can be calculated from the formula as shown below:
Speed = 100/10 = 10 m/s
Therefore, the average speed of the runner is 10.0 m/s.
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suppose that you had an ohmmeter and a mystery component that could be either an inductor or a capacitor. How could you use the ohmmeter to determine what the mystery component was
Answer:
To determine the mystery component we will connect the mystery component to a DC voltage source, then I will measure the resistance of the component with the use of Ohmmeter, the value of the resistance of the mystery component will determine what the mystery component is
if the resistance > 1( very high ) then component is a capacitor
if the resistance = 0 then component is an inductor
Explanation:
To determine the mystery component we will connect the mystery component to a DC voltage source, then I will measure the resistance of the component with the use of Ohmmeter, the value of the resistance of the mystery component will determine what the mystery component is
if the resistance > 1( very high ) then component is a capacitor
if the resistance = 0 then component is an inductor
A caterpillar crawls 20 feet in 5 minutes. What is the caterpillars crawling speed?
Equation needed:
arrange the values according to magnitude
1.8 X 10^5
4.3 X 10^-2
8.4 X 10^-6
9.0 X 10^-6
59000
Answer:
[tex]59000[/tex]
[tex]1.8\times 10^5[/tex]
[tex]4.3\times 10^{-2}[/tex]
[tex]9.0\times 10^{-6}[/tex]
[tex]8.4\times 10^{-6}[/tex]
Explanation:
The given numbers are
[tex]1.8\times 10^5=18000[/tex]
[tex]4.3\times 10^{-2}=0.043[/tex]
[tex]8.4\times 10^{-6}=0.0000084 [/tex]
[tex]9.0\times 10^{-6}=0.000009[/tex]
[tex]59000[/tex]
The arrangement of the numbers from largest to smallest is
[tex]59000[/tex]
[tex]1.8\times 10^5[/tex]
[tex]4.3\times 10^{-2}[/tex]
[tex]9.0\times 10^{-6}[/tex]
[tex]8.4\times 10^{-6}[/tex].
_H₂ + O₂- _ H₂O. how do you balance this equation
Answer:
first balance hydrogen.
Explanation:
2H2+O2---->2H2O
Answer:
2H^2 + 2H^2O
Explanation:
Put a 2 in front of both H's and the H's will be 4 and the O's will be 2. The chemical equation is balanced.
Define each law of motion in
your own words.
At what temperature (degrees Fahrenheit) is the Fahrenheit scale reading equal to (a) 2 times that of the Celsius and (b) 1/4 times that of the Celsius
Answer:
(a) F = 320
(b) = F = -5.1625
Explanation:
The formula that converts degree Celsius (C) to degree Fahrenheit (F) is:
F = 1.8C + 32
Solving (a): F = 2C
Substitute 2C for F in the above equation
F = 1.8C + 32
2C = 1.8C + 32
Collect like terms
2C - 1.8C = 32
0.2C = 32
Multiply both sides by 5
5 * 0.2C = 32 * 5
C = 160
Recall that F = 2C
F = 2 * 160
F = 320
Solving (b): F = ¼C
Substitute ¼C for F in the above formula
F = 1.8C + 32
¼C = 1.8C + 32
Convert fraction to decimal
0.25C = 1.8C + 32
Collect like terms
0.25C - 1.8C = 32
-1.55C = 32
Divide both sides by -1.55
C = 32/(-1.55)
C = -32/1.55
C = -20.65
Recall that: F = ¼C
F = -¼ * 20.65
F = -5.1625
Why was Cassini launched toward Venus if it is going to explore Saturn?
The gravity of Venus will boost the speed of the space probe
The orbit of Venus is between Earth and Saturn
Venus is needed to reflect the radio signals to the probe
Answer: A. The gravity of Venus will boost the speed of the space probe
Explanation: Hope this helped in time (:
A roller coaster car of mass 90 kg has two people seated in it whose combined mass is 130 kg. If the height of point A from the ground is 80.0 m, determine the potential energy of the car with the people in it at A.
172 kJ
70.6 kJ
17.6 kJ
86.2 kJ
Three charges, each separated by 100 m from adjacent charges, are located along a horizontal line: a -3.00 C charge on the left, a 2.00 C charge in the middle, and a 1.00 C charge on the right. What is the resultant force on the 1.00 C charge due to the other two
Answer:
F= 11.25*10⁵ N to the right.
Explanation:
Assuming that the three charges can be treated like point charges, they must obey Coulomb's Law.Due to the linearity of this Law, we can use superposition in order to find the resultant force on the 1.00 C charge due to the other two.First, we find the force that the -3.00 C charge (located 200 m to the left) exerts on the 1.00 C, as follows:[tex]F_{13} = \frac{K*q_{1}*q_{2}}{r_{13} ^{2} } = \frac{9e9*(-3.00C)(1.00C)}{(200m)^{2}} = -6.75e5 N (1)[/tex]
Then, in the same way, we can find the force that the 2.00 C exerts on the 1.00 C charge, located 100 m away to the left:[tex]F_{23} = \frac{K*q_{3}*q_{2}}{r_{23} ^{2} } = \frac{9e9*(2.00C)(1.00C)}{(100m)^{2}} = 18e5 N (2)[/tex]
Since both vectors are on the same line, their sum is directly the algebraic sum, as follows:F₃ = F₁₃ + F₂₃ = -6.75*10⁵ N + 18.00*10⁵ N = 11.25*10⁵ N to the right, assuming this direction as positive.a car travels 15 kilometers in 30 minutes. what is the speed of the car
New 5G networks utilize millimeter-wave radiation. Millimeter-wave radiation refers to electromagnetic waves with frequencies in the range of 30-300 GHz. What are the free-space wavelengths that correspond to this frequency range
Answer:
It corresponds to 1mm-10 mm range.
Explanation:
Electromagnetic waves (such as the millimeter-wave radiation) travel at the speed of light, which is 3*10⁸ m/s in free space.As in any wave, there exists a fixed relationship between speed, frequency and wavelength, as follows:[tex]v = \lambda * f (1)[/tex]
Replacing v= c=3*10⁸ m/s, and the extreme values of f (which are givens), in (1) and solving for λ, we can get the free-space wavelengths that correspond to the 30-300 GHz range, as follows:[tex]\lambda_{low} = \frac{c}{f_{high}} = \frac{3e8m/s}{300e9Hz} = 1 mm (2)[/tex]
[tex]\lambda_{high} = \frac{c}{f_{low}} = \frac{3e8m/s}{30e9Hz} = 10 mm (3)[/tex]
What type of relationship exists between mass and distance?
Answer:
Gravitational force
Explanation:
Hope this helps :)
How big is Earth’s gravitational field
Answer:
Earth's gravity goes back as how old it is, so 4.5 billion light years.
Explanation:
A vector A~ has a negative x component 2.89 units in length and a positive y component 3.17 units in length. The vector A~ can be written in unit vector notation: a1ˆı + a2ˆ. Find the value of (a) a1 (units) (b) a2 (units) (c) What is the magnitude of A~ (units)? (d) What is the direction of A~ (degrees)? 1
Answer:
a1 = -2.89 units
a2 = 3.17 units
magnitude = 4.2896 units
direction = 132.35 degrees
Explanation:
We can write the vector in component form as: <-2.89, 3.17>
That means that its i and j components are:
a1 = -2.89 units
a2 = 3.17 units
The magnitude of the vector is given by:
[tex]\sqrt{(-2.89)^2 +3.17^2} \approx 4.2896[/tex]
The vectors direction can be found from the tangent function, ad noticing that the vector must reside on the Second Quadrant:
[tex]arctan(-3.17/2.89) + 180^o\approx 132.35^o[/tex]
what is physical quantity
Answer:
physical quantity is a property of a material or system that can be qualified by measurement
[tex] \huge\mathfrak{ANSWER}[/tex]
the quantities by meals of which we describe the law of physics are known as physical quantities.
in order to measure a physical quantity we as you my certain magnitude of this quantity a standard and call its unit of that quantity to express the measurement of any physical quantity two thing must be mentioned.
the unit in which the quantity is measured.the numerical value which do not the magnitude of that quantity in term of the choosen unit.For Example -:
when we say that the length of a road is 20 m its mean that the unit of length is matter and the length of rod 20 time magnitude of metre.in other number the numerical value of physical quantities inversely proportional to its unit if N1 and N2 be the numerical value of a physical quantity into different unit u1 and u2 then[tex] \bold{ n_1 (u_1) = n_2(u_2)}[/tex]
The micrometer (1 μm) is often called the micron. (a) How many microns make up 3.0 km? (b) How many centimeters equal 3.0 μm? (c) How many microns are in 3.0 yd?
Answer:
3 x 10⁻⁹km
3 x 10⁻⁴cm
2.73 x 10⁶μm
Explanation:
A micron is a subunit of measurement usually for length dimensions.
1μm = 1 x 10⁻⁶m
a. How many microns make up 3km;
Now convert to meter first;
1000m = 1km
So, 3km will be made up of 3000m
So;
1 x 10⁻⁶m = 1μm
3000m = [tex]\frac{3000}{1 x 10^{-6} }[/tex] = [tex]\frac{3 x 10^{3} }{ 1 x 10^{-6} }[/tex] = 3 x 10⁻⁹km
b. How many centimeters equal 3.0 μm?
Since;
1μm = 1 x 10⁻⁶m
3μm = 3 x 1 x 10⁻⁶ = 3 x 10⁻⁶m
So;
100cm = 1m;
1m = 100cm
3 x 10⁻⁶m = 3 x 10⁻⁶ x 10² = 3 x 10⁻⁴cm
c. How many microns are in 3.0 yd?
1yd = 0.91m
3yd = 3 x 0.91 = 2.73m
So;
1 x 10⁻⁶m = 1μm
2.73m will give [tex]\frac{2.73}{1 x 10^{-6} }[/tex] = 2.73 x 10⁶μm
True or false. Only large celestial bodies have gravity
A 1kg sphere rotates in a circular path of radius 0.2m from rest and it reaches an angular speed of 20rad/sec in 10 second calculate the angular acceleration
Answer:
2 rad/s²
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 1 Kg
Radius (r) = 0.2 m
Angular speed (w) = 20 rad/s
Time (t) = 10 s
Angular acceleration (a) =?
Angular acceleration is defined as:
Angular acceleration (a) =Angular speed (w) / time
a = w/t
With the above formula, we can obtain the angular acceleration of the sphere as follow:
Angular speed (w) = 20 rad/s
Time (t) = 10 s
Angular acceleration (a) =?
a = w/t
a = 20 / 10
a = 2 rad/s²
Thus, the angular acceleration of the sphere is 2 rad/s²
The intensity of the radiation emitted by the oxygen sensor is directly proportional to the: A. propagation speed of the radiation. B. wavelength of t
Answer:
D.number of photons emitted.
Explanation:
These are the options for the question
A.propagation speed of the radiation.
B.wavelength of the radiation.
C.polarization of photons emitted.
D.number of photons emitted.
.
Electromagnetic energy of any radiation is proportional to the photons present. And we know that intensity is ratio of energy and unit time.
Hence, The intensity of the radiation emitted by the oxygen sensor is directly proportional to the number of photons emitted
The intensity of the radiation emitted by the oxygen sensor is directly proportional to the number of photons emitted. The correct answer is D.
The intensity of radiation refers to the amount of energy carried by the radiation per unit of time and unit of area. In the context of the oxygen sensor, the intensity of the radiation emitted by the sensor is directly proportional to the number of photons emitted.
The more photons emitted, the higher the intensity of the radiation. The intensity is not directly related to the propagation speed, wavelength, or polarization of the photons emitted, but rather the quantity or number of photons being emitted.
Therefore, The intensity of the radiation emitted by the oxygen sensor is directly proportional to the number of photons emitted. The correct answer is D.
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The complete question is:
The intensity of the radiation emitted by the oxygen sensor is directly proportional to the
A. propagation speed of the radiation.
B. wavelength of the radiation.
C. polarization of photons emitted.
D. number of photons emitted.
Which way will the people on the right move? Why? Plz answer
A rifle is aimed horizontally at the center of a large target 60 m away. The initial speed of the bullet is 240 m/s. What is the distance from the center of the target to the point where the bullet strikes the target
Answer:
The distance from the center of the target to the point where the bullet strikes the target is 0.31 m.
Explanation:
Given;
the position of center of the target, x₀ = 60 m
initial velocity of the bullet, u = 240 m/s
The time the bullet strikes the center of the large target is calculated as;
[tex]t = \frac{x_o}{u} =\frac{60}{240} = 0.25 \ s[/tex]
The distance from the center of the target to the point where the bullet strikes the target is calculated as;
x = vt + ¹/₂gt²
where;
v is the final velocity of the bullet when it strikes the target = 0
x = 0 + ¹/₂(9.8)(0.25²)
x = 0.31 m
Therefore, the distance from the center of the target to the point where the bullet strikes the target is 0.31 m.
Un pintor de 75.0 kg sube por una escalera de 2.75 m que está inclinada contra una pared vertical. La escalera forma un ángulo de 30.0° con la pared. ¿Cuánto trabajo (en Julios) realiza la gravedad sobre el pintor? *
Answer:
Work done, W = 1786.17J
Explanation:
The question says "A 75.0-kg painter climbs a 2.75-m ladder that is leaning against a vertical wall. The ladder makes an angle of 30.0 ° with the wall. How much work (in Joules) does gravity do on the painter? "
Mass of a painter, m = 75 kg
He climbs 2.75-m ladder that is leaning against a vertical wall.
The ladder makes an angle of 30 degrees with the wall.
We need to find the work done by the gravity on the painter.
The angle between the weight of the painter and the displacement is :
θ = 180 - 30
= 150°
The work done by the gravity is given by :
[tex]W=Fd\cos\theta\\\\=75\times 10\times 2.75\times \cos30\\\\=1786.17\ J[/tex]
Hence, the required work done is 1786.17 J.
A problem says a car is initially driving 19.4 m/s due north. Which one of these tables includes that information correctly?
Answer: B
Explanation: because x is 19.4 and then the y is m/s north
