Answer:
Object's weight = 6,839.42 N
Explanation:
Given
Above waterline = 30%
Volume of object = 1m^3
Required
Determine the weight of the object
First, we need to calculate its Mass
Mass = Density of Water * Volume of object in water
Density of water = 997kg/m³
If 30% is above waterline, then 70% is in water.
So:
Mass = Density of Water * Volume of object in water
Mass = 997kg/m³ * 70%m³
Mass = 997kg * 70%
Mass = 697.9 kg
The object weight sis then calculated as thus:
Weight = Mass * Acceleration of gravity
Weight = 697.9 kg * 9.8m/s²
Weight = 6 839.42 N
I need help understanding this question, so I know the arrow is traveling 80 meters per second, but it was launched from a starting point of 32 meters. I know for a fact an arrow does not have any thrust left at around 3 seconds of being in the air.
I just need someone to explain the questions and provide an answer to each.
Answer:
a) h(g) = 358,53 m
b) t = 8,16 s
c) t(t) = 16,71 s
Explanation:
Equations for vertical shooting are:
Vf = V₀ - g * t ; h = V₀*t - (1/2)*g*t² ; Vf² = V₀² - 2*g*h
And at maximum heigt Vf = 0 then
0 = V₀ - g * t
t = V₀/g V₀ = 80 m/s and g = 9,8 m/s²
t = 80 / 9,8 (s)
t = 8,16 s
Then 8,16 s is the time to get maximum height
If we plug t = 8,16 (s) in equation h = V₀*t - (1/2)*g*t²
we get: h (max) = (80)*8,16 - 0,5*9,8*(8,16)² (m)
h (max) = 652,8 - 326,27 m
h (max) = 326,53 m
Then relative to ground that height becomes
h(g) = 326,53 + 32
h(g) = 358,53 m
In order to get the time the arrow is in the air we proceed as follows:
a) for the arrow to be at the launched point will take the same time that from the launched point to the maximum height, and after that we have to find out the time the arrow takes from 32 m down to the ground level
Then
t(t) = 8,16 + 8,16 + tₓ (2)
Where tₓ is the time from 32 m height to ground
h = V₀*tₓ - (1/2)*g*tₓ² but since the arrow now is going down then we change the sign of the second term on the right side of the equation
32 = (80)*tₓ + 0,5 * 9,8 * tₓ² Note that when the arrow is at 32 m height the speed is again V₀ = 80 m/s
32 = 80*tₓ + 4,9*tₓ²
A second-degree equation for tₓ, solving it
4,9*tₓ² + 80*tₓ - 32 = 0
t₁,₂ = -80 ± √ 6400 + 627,2 / 9,8
t₁,₂ =( - 80 ± 83,8 ) / 9,8
there is not a negative time therefore we dismiss such solution and
t₁ = 3,8 / 9,8
t₁ = 0,39 s
And
t(t) = 8,16 + 8,16 + 0,39 s
t(t) = 16,71 s
A rocket will move upward as long as which condition applies?
1. The mass of the Earth is 81 times the mass of the Moon. Using Newton's Law of Gravity, what would the effect of gravitation be if the mass of the Moon were increased by four times and the distance between Earth and
the Moon were cut in half?
Answer:
effects of gravity on the Moon and Earth
Explanation: Newton found the Moon's inward acceleration in its orbit to be 0.0027 metre per second per second, the same as (1/60)2 of the acceleration of a falling object at the surface of Earth.
How long does it take a plane, traveling at a constant speed of 123 m/s, to fly once around a circle whose radius is 4330 m?
Answer:
3.7 minExplanation:
Step one:
given data
speed = 123m/s
radius of circle= 4330m
Step two:
We need to find the circumference of the circle, it represents the distance traveled
C=2πr
C= 2*3.142*4330
C= 27209.72m
Step three:
We know that velocity= distance/time
time= distance/velocity
time= 27209.72/123
time=221.2 seconds
in minute = 221.2/60
time= 3.7 min
Which change in an object would increase the force needed to move the object?
А.
decreasing the velocity of an object
B
increasing the volume of an object
с
decreasing the mass of an object
D
increasing the mass of an object
Answer:
D i think
Explanation:
Heavier objects (objects with more mass) are more difficult to move and stop.
Answer:
Increasing the mass of the object (option D in the list of answers)
Explanation:
Recall that F = m x a
therefore, if the mass increases, the force increases
One of the harmonics of a column of air in a tube that is open at both ends has a frequency of 448 Hz, and the next higher harmonic has a frequency of 576 Hz. What is the fundamental frequency of the air column in this tube?
Answer:
The fundamental frequency is [tex]f_1 =128 \ Hz[/tex]
Explanation:
From the question we are told that
The frequency of one harmonics is [tex]f_x= 448 \ Hz[/tex]
The next higher harmonic is [tex]f_z = 576 \ Hz[/tex]
Generally the frequency of an air column open at both ends is mathematically represented as
[tex]f_n = \frac{nv }{ 2 L }[/tex]
Here n is the order of the harmonics (frequency)
v is the velocity of the sound
L is the length of the column
So for one harmonics we have that
[tex]f_k = \frac{n v }{2L}[/tex]
Then for the next higher harmonics
[tex]f_x = \frac{n+1 ) v}{2 L }[/tex]
Generally the difference between these frequencies is mathematically represented as
[tex]f_z- f_x = \frac{(n+1 )v}{ 2L} - \frac{(n )v}{ 2L}[/tex]
=> [tex]576 - 448 = \frac{vn + v - nv }{2L}[/tex]
=> [tex]\frac{ v }{2L} = 128[/tex]
Generally for fundamental frequency n = 1
So
[tex]f_1 = n * \frac{v}{2L}[/tex]
So
[tex]f_1 =1 * 128[/tex]
=> [tex]f_1 =128 \ Hz[/tex]
one newton equals 0.225
The glowing dot represents the transmission of a nerve impulse along the nerves that make up the neural pathway. A nerve impulse is an electrical signal that travels from one nerve cell to another.
Which part of the brain processes this signal?
Answer:
The answer is "Cerebral Cortex"
Explanation:
The neurotransmitter diffuses across the short distance of the synapse and ties to a receptor protein of the objective neuron. At the point when the sub-atomic sign ties to the receptor, the cell film of the objective neuron changes its electrical state and another evaluated expected starts. On the off chance that that evaluated potential is sufficiently able to arrive at limit, the subsequent neuron produces an activity potential at its axon hillock. The objective of this neuron is another neuron in the thalamus of the mind, the piece of the CNS that goes about as a transfer for tactile data.
At another neurotransmitter, synapse is delivered and ties to its receptor. The thalamus at that point sends the sensory information to the cerebral cortex, the furthest layer of dark issue in the brain, where cognizant view of that water temperature starts.
A region of the cortex is particular for imparting signs down to the spinal cord for development. The upper engine neuron is in this area, called the precentral gyrus of the frontal cortex, which has an axon that broadens right down the spinal cord. At the degree of the spinal cord at which this axon makes a neurotransmitter, a reviewed potential happens in the cell membrane of a lower engine neuron.
A merry-go-round on a playground consists of a horizontal solid disk with a weight of 805 N and a radius of 1.58 m. A child applies a force 49.5 N tangentially to the edge of the disk to start it from rest. What is the kinetic energy of the merry-go-round disk (in J) after 2.95 s?
Answer:
The value is [tex]KE = 259.6 \ J[/tex]
Explanation:
From the question we are told that
The weight of the horizontal solid disk is [tex]W = 805 \ N[/tex]
The radius of the horizontal solid disk is [tex]r = 1.58 \ m[/tex]
The force applied by the child is [tex]F = 49.5 \ N[/tex]
The time considered is [tex]t = 2.95 \ s[/tex]
Generally the mass of the horizontal solid disk is mathematically represented as
[tex]m_h = \frac{W}{ g}[/tex]
=> [tex]m_h = \frac{805}{ 9.8 }[/tex]
=> [tex]m_h = 82.14 \ N[/tex]
Generally the moment of inertia of the horizontal solid disk is mathematically represented as
[tex]I = \frac{1}{2} * m * r^ 2[/tex]
=> [tex]I = \frac{1}{2} * 82.14 * 1.58^ 2[/tex]
=> [tex]I = 102.5 \ kg \cdot m^2[/tex]
Generally the net torque experienced by the horizontal solid disk is mathematically represented as
[tex]T = I * \alpha = F * r[/tex]
=> [tex]\alpha = \frac{ F * r }{ I }[/tex]
=> [tex]\alpha = \frac{ 49.5 * 1.58 }{ 102.53 }[/tex]
=> [tex]\alpha = 0.7628[/tex]
Gnerally from kinematic equation we have that
[tex]w = w_o + \alpha t[/tex]
Here [tex]w_o[/tex] is the initial angular velocity velocity of the horizontal solid disk which is [tex]w_o = 0\ rad/s[/tex]
So
[tex]w = 0 + 0.7628 * 2.95[/tex]
=> [tex]w = 2.2503 \ rad/s[/tex]
Generally the kinetic energy is mathematically represented as
[tex]KE = \frac{1}{2} * I * w^2[/tex]
=> [tex]KE = \frac{1}{2} * 102.53 * 2.2503 ^2[/tex]
=> [tex]KE = 259.6 \ J[/tex]
There is a bell at the top of a tower that is 45 m high. The bell weighs 190 N. The bell has ____________ energy.
Answer:
The bell has 8,550 Joule energy.
Explanation:
Gravitational Potential Energy
Gravitational potential energy is the energy stored in an object because of its height in a gravitational field.
It can be calculated with the equation:
U=m.g.h
Where:
m = mass of the object
h = height
g = acceleration of gravity, or [tex]9.8 m/s^2[/tex]
Since the weight of an object of mass m can be calculated as:
W = m.g
The gravitational potential energy is:
U = W.h
The bell of weight W=190 N at the top of a tower is h=45 m high. Thus its energy is:
U = 190 N . 45 m
U = 8,550 Joule
The bell has 8,550 Joule energy.
A 12 kg coyote runs towards a rabbit in the Ortega Mountains
with a velocity of 8 m/s. Determine the momentum of the
coyote.
What is "given" in the word problem?
A) mass and velocity
B) momentum
C) momentum and mass
D) momentum and velocity
Given :
A 12 kg coyote runs towards a rabbit in the Ortega Mountains with a velocity of 8 m/s.
To Find :
The momentum of the coyote.
Solution :
The given in the question is mass of coyote which is 12 kg and velocity which is 8 m/s .
Momentum is given by :
M = mass × velocity
M = 12 × 8 kg m/s
M = 96 kg m/s
Hence, this is the required solution.
What is the velocity of an object after falling for 15 seconds, neglecting air resistance? (g=9.81)
O 77.499
O 0.64m/s^2
O 15.53 m/s to the left.
147.15 m/s downward.
Answer:
(ans147.15m/s downward)
Explanation:
initial velocity (u)=0m/s
final velocity (v)=?
v=u+gt. ( t)time taken=15seconds
?=0+(9.81)×15
?=147.15m/s
hope this helped
Introduction to Simple Machines
This activity will help you meet this educational goal:
You will compare and contrast information from a video with information from a text.
Directions
Read the instructions for this self-checked activity. Type in your response to each question, and check your answers. At the end of the activity, write a brief evaluation of your work.
Activity
Watch this video and then answer the following questions based on what you learned.
Part A
How does a bicycle make work easier?
Part B
Which two examples of levers are mentioned in the video?
The picture shows a bicycle’s pedals. Look at the shaft that the pedals are attached to. Do you think the shaft is a lever? Why or why not?
Answer:
word for word answers!
Explanation:
1) Part A: By pedaling a bicycle lightly, the rider can go a long way
2) Part B: The two examples mentioned in the video are the handlebars and the brakes
3) Yes, it’s a type of lever because the two pedals rotate around a fixed point
which of the following is true of phototsythesis but not of cellular respiration.
A- Photosynthesis releases oxygen gas as a product
B- Photosynthesis occurs in all organisms
C- Photo synthesis is a process in which glucose i broken down
D- Photosynthesis requires glucose as a reactant
Answer:
B. Photosynthesis occurs in all organisms
Hope this helps!! :)
A statement of the second law of thermodynamics is that:__________.
a) spontaneous reactions are always exothermic.
b) energy is conserved in a chemical reaction that has a decrease in entropy.
c) spontaneous reactions are always endothermic.
d) in a spontaneous process, the entropy of the universe increases.
Answer:
in a spontaneous process, the entropy of the universe increases.
Explanation:
Entropy is a measure of of the degree of randomness or disorderliness in a system.
The second law of thermodynamics can be stated as follows; "in any spontaneous process, the entropy of the universe increases."
The universe here refers to the system's disorder and the disorder of the surroundings. Therefore, a spontaneous process can occur, in which the entropy of the system decreases, only if the entropy increases in the surroundings.
For instance, when ice freezes, the entropy of liquid water decreases, that is, the entropy of the system decreases. However, heat is given off to the surroundings and the entropy of the surroundings increases. This is an obvious expression of this law.
The free-body diagram below shows the forces acting on a bicycle as the
rider pedals to the right. The vectors are not drawn to scale. The bicycle has a
weight of 800 N and a pedaling force of 250 N. As it moves, it encounters 75
N of air resistance. What is the net force on the bicycle in the x-direction?
Answer:
175 N to the right
Explanation:
I am taking the quiz and this is the correct answer. The pedaling force if 250 N but when it encounters 75 N of air resistance, it reduces to 175 N. This is because the air resistance is going opposite of you.
The weight of the bike and the cyclist are a force that the Earth applies to both of them and that acts vertically and downward, causing an action on the ground. The pedal-pushing force is transmitted from the crank arm to the chainring axis via the transmission forces.
What forces acting on a moving bicycle?When we press the pedals, the force travels to the back wheel, which then applies pressure to the ground. Strength of action. The pavement responds by exerting a force in the opposite direction but in the same direction on the back wheel. Hence, always move forward.
Therefore, Walking and biking are made possible through la friction. The friction created by the tire's pressure on the ground, It prevents the tire from rotating and keeps the lowest part of the wheel on the ground. The wheel is driven by this force, which is transferred to the wheel axle.
Learn more about forces here:
https://brainly.com/question/13191643
#SPJ2
John decided to cycle to his friend's house at a speed of 5km/h and the journey took 2
hours. How far did John cycle?
Answer:100 miles
Explanation:
Answer:
10 Km
Explanation:
He is going 5km per hour and he arrived at his friend's house in 2 hours. You multiply 5 by 2 and you get 10.
A metal box of weigh 20 N rests on its 1 m by 0.6m side on floor. How
much is the pressure exerted by the metal box on the floor? Take g=
10 m/s
Answer:
P = 33.33 [Pa]
Explanation:
The pressure can be calculated by the relationship of the force over the area.
[tex]P =F/A[/tex]
where:
F = force = 20 [N]
A = area = 1 x 0.6 = 0.6 [m²]
Now replacing:
[tex]P=20/0.6\\P=33.33 [Pa][/tex]
While getting buff at the gym you lift a bunch of weights applying 1000N of force to lift them from the ground to a height of 2m. How much work did you do?
A. 2000 J
B. 1000J
C. -2000 J
D. -1000 J
A certain heat engine does 30.2 kJ of work and dissipates 9.14 kJ of waste heat in a cyclical process.
A) What was the heat input to this engine?
B) What was its efficiency?
Answer:
a) [tex]H_{in}=39.34 kJ[/tex]
b) Efficiency=76.77%
Explanation:
a)
In order to solve this problem, we can use the following formula:
[tex]H_{in}=H_{out}+W[/tex]
the problem provides us with all the necessary information so we can directly use the formula:
[tex]H_{in}=9.14kJ+30.2kJ[/tex]
[tex]H_{in}=39.34 kJ[/tex]
b) In order to find the efficiency, we can use the following formula:
[tex]Efficiency=\frac{W}{H_{in}}*100\%[/tex]
so we get:
[tex]Efficiency=\frac{30.2kJ}{39.34kJ}*100\%[/tex]
Efficiency=76.77%
