Answer:
W = 41.45 Kcal
Explanation:
Given that,
The mass of a person, m = 75 kg
He climbs 248 steps to the top of the Cape Hatteras lighthouse, a total climb of 59 m.
We need to find how many calories does he or she burn.
Work done = Fd
d is displacement
⇒ W = 75 ×9.8 ×59
= 43365 J
Let the efficiency is 0.25.
[tex]W=\dfrac{43365}{0.25}\\\\=173460\ J\\\\\text{or}\\\\=41.45\ kcal[/tex]
So, 41.45 Kcal is burned by the person.
PLEASE ANSWER FAST ill give brainliest
let's say you hypothetically ran over someone with your car, and they are now under your car in between the front wheels and the back wheels, right, and they're stuck as in can't breathe type stuck, right, do you keep driving so they can breathe or do you let them chill under your car?
just curious...
question: is this actually hypothetical?
Explanation:
also just leave the car there go get some McDonald's or sum and come back and if they're still breathing then go ahead and move the car .
Answer:
the same thing the last guy said
how much KE does the car have if it weighs 450kg and moves at the speed of 23 m/s?
Answer:-The formula of to calculate KE = 1/2 m v^2
so we,
KE = 1/2 (450kg)(23m/s)^2
KE = 1/2 ×238050
KE = 119025
Explanation: In Physics Formulas mean everything.
Suppose that when spring was wound, 100J of work was done but 15J escaped to the surrounding as heat. The change in internal energy of the spring is?
Answer: 85J
Explanation:
From the question, we are informed that when spring was wound, 100J of work was done but 15J escaped to the surrounding as heat.
Therefore, the change in internal energy of the spring will be calculated as:
ΔU = q + w
where, q = -15J
w = 100J
ΔU = -15J + 100J
= 85J
Find the applied voltage of a telephone circuit that draws 0.017A through a resistance Of 5,000 ohms
A person lifts a heavy load to a vertical height of 2.0 m in 3 seconds. If he/she had done this more slowly in 6 seconds, the
work on the load would have been:
Four times as great
half as great
the same
twice as great
Answer:
If the heavy load had been lifted more slowly, the work done on the load would have been the same.
Explanation:
Work done on an object is given as;
W = Fd
where;
F is the force applied on the object
d is the displacement of the object
for the given question, the applied force on the load = mg (mass of the load multiplied by acceleration due to gravity).
Also, the displacement of the object = vertical height the load was lifted.
W = mgh
The work done on the load is independent of time.
Thus, if the heavy load had been lifted more slowly, the work done on the load would have been the same.
A person lifting a heavy load to a vertical height of 2.0 m in 3 seconds does the same work as if he/she lifts it in 6 s.
A person lifts a heavy load to a vertical height of 2.0 m in 3 seconds.
We want to compare the work done with the one that he/she would have done if the process had taken 6 seconds.
What is work?In physics, work (W) is the energy transferred to or from an object via the application of force (F) along a displacement (s).
W = F × s
Given the displacement is the same (2.0 m) and the force needed is also the same (weight of the object), the work is the same for both processes.
A person lifting a heavy load to a vertical height of 2.0 m in 3 seconds does the same work as if he/she lifts it in 6 s.
Learn more about work here: https://brainly.com/question/25064916
Please answer the questions... I will surely mark you as the brainliest according to me :)
Answer:
(a) You can tell that have the same strength because they have attracted the same amount of paper clips.
(b) Iron is used in electromagnets because steel retained magnetic properties after the power was turned off, but in the iron, the paper clips dropped off right away.
Which of these is another name for Newton's
first law?
A. the law of action-reaction
B. the law of force and acceleration
C. the law of gravity
D. the law of inertia
How can land that was formerly used as dumps, mines, or factory sites be.
rehabilitated?
Answer:
clear out the junk, and plant some stuff
Explanation:
clear out all of the nasties, unless it is biodegradable, or you could get some mushrooms to break everything down, then you can go and plant some stuff or do whatever. You could turn it into a playground, park, whatever.
1. Determine the kinetic energy of a 625-kg roller coaster car that is moving with a speed of 18.3 m/s,
Answer:
104653.13J
Explanation:
Given parameters:
Mass of roller coaster = 625kg
Speed = 18.3m/s
Unknown:
Kinetic energy = ?
Solution:
The kinetic energy is the energy due to the motion of a body.
Kinetic energy = [tex]\frac{1}{2}[/tex] x m x v²
m is the mass
v is the speed
Kinetic energy = [tex]\frac{1}{2}[/tex] x 625 x 18.3² = 104653.13J
which is true about the way air flows
A. high pressure to low pressure
B. low pressure to high pressure
C. cold air to hot air
D. hot air to cold air
Answer:
A High-to-Low
Explanation:
its like water running down a hill.
fill in the blank:
the more people (greater mass) you load into a car, the ___ (more or less) it will accelerate with the same force applied by the engine.
the more people (greater mass) you load into a car, the more it will accelerate with the same force applied by the engine.
A volleyball experiences 494 Ns of impulse over a time period of 7 seconds. What was the magnitude of the force that acted on the volleyball during this time period?
Answer:
70.6N
Explanation:
Given parameters:
Impulse = 494Ns
Time = 7s
Unknown:
Force applied = ?
Solution:
To solve this problem, we use the formula of impulse;
Impulse = Force x time
Now insert the parameters and solve;
494 = Force x 7
Force = [tex]\frac{494}{7}[/tex]
Force = 70.6N
What is the standard form for 2 × 10−3 ?
Answer:
17
Explanation:
2 x 10 = 20
20-3 = 17
If two cars A and B are moving with velocity 60 km/hr and 80 km/hr
respectively in thesamedirection. What willbethe relative velocity of B with
respect to A? (20 kmhr)
Answer:
VAB = 20km/hr
Explanation:
Given the following data;
Velocity of car A, VA = 60km/hr
Velocity of car B, VB = 80km/hr
To find the relative velocity of B w.r.t A, VAB;
Since the two cars are moving in the same direction, we have;
VAB = VB - VA
Substituting into the equation, we have;
VAB = 80 - 60
VAB = 20km/hr
Therefore, the relative velocity of car B with respect to car A is 20 kilometers per hour.
diffrence between:- movable pulley and fixed pully
Answer:
fixed pulley: A pulley system in which the pulley is attached to a fixed point and the rope is attached to the object. ... movable pulley: A pulley system in which the pulley is attached to the object; one end of the rope is attached to a fixed point and the other end of the rope is free.
Explanation:
A 1.3-kg model airplane flies in a circular path on the end of a 23-m line. The plane makes
4.3 revolutions each minute.
a. What is the period of the motion?
b. What is the speed of the plane?
c. What is the acceleration of the model plane?
d. How much force must the line exert on the plane to keep it moving in the circular
motion?
(a) The plane makes 4.3 revolutions per minute, so it makes a single revolution in
(1 min) / (4.3 rev) ≈ 0.2326 min ≈ 13.95 s ≈ 14 s
(b) The plane completes 1 revolution in about 14 s, so that in this time it travels a distance equal to the circumference of the path:
(2π (23 m)) / (14 s) ≈ 10.3568 m/s ≈ 10 m/s
(c) The plane accelerates toward the center of the path with magnitude
a = (10 m/s)² / (23 m) ≈ 4.6636 m/s² ≈ 4.7 m/s²
(d) By Newton's second law, the tension in the line is
F = (1.3 kg) (4.7 m/s²) ≈ 6.0627 N ≈ 6.1 N
a string attached to a 60.0 Hz vibr.ator creates a standing wave with 5 loops. What frequency would make 7 loops? (Unit = Hz)
Answer:
F=84.0 Hz
Explanation:
Using the equation f= n (v/2L), frequency equals number of loops times velocity over 2 times the length, in order to get 60.0 Hz of frequency from 5 loops, v/2L would have to equal 12. (12*5=60) v/2L is constant, so to find the frequency of 7 loops you would times 7 by 12 to get 84.0.
Hope this helped! :)
5) Choose the best revision of the following statement: "All the isotopes of a particular element decay radioactively by
emitting electrons."
A. All the isotopes of a particular element are stable and do not decay.
B. Some isotopes are stable and others are unstable. Unstable isotopes decay by emitting various subatomic
particles and radiation
C. Some isotopes are stable and others are unstable. Unstable isotopes decay by emitting protons or
electrons.
D. The statement is correct as it is currently written.
Answer:
B. some isotopes are stable and others are unstable. unstable isotopes decay by emitting various subatomic particles and radiation.
Explanation:
test gave me the answer so yeah :/ XD
Using a pulley, you apply a force of 10 Newtons to life an object that weighs 100 Newtons. What is the mechanical advantage of that pulley?
Answer: 10
Explanation:
The mechanical advantage of that pulley is 10.
What is mechanical advantage?The force amplified by utilizing a tool, mechanical device, or machine system is known as mechanical advantage. To achieve the desired output force amplification, the gadget trades off input forces against movement. The law of the lever serves as a paradigm for this.
Mechanisms are machine parts made to control forces and motion in this way.
Given that: the weighs of the object: W = 100 Newton.
Applied force: F = 10 N.
For using a pulley, you have to apply a force of 10 Newtons to lift an object that weighs 100 Newtons.
Hence, the mechanical advantage of the pulley is
= Weighs of the object/applied force
= 100 Newton / 10 Newton.
= 10.
The mechanical advantage of it is 10.
Learn more about mechanical advantage here:
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What happens to most of the light waves that strike a clear pane of glass? O A. absorption B. diffraction O C. reflection O D. transmission
slight reflect but most goes through because glass is transparent
Most of the light waves that strike a clear pane of glass reflects. Details about reflection can be found below.
What is reflection?Refection in physics is the property of a propagated wave being thrown back from a surface such as a mirror.
Mirror is an example of an object that could be hit by an incumbent wave, however, most of the light waves that hit the mirror surface gets reflected back.
Therefore, most of the light waves that strike a clear pane of glass reflects.
Learn more about refection at: https://brainly.com/question/15487308
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How long does it take for a bee traveling 11.34 m/s to fly 120 m?
A bullet has a mass of 0.06 kg. Starting from rest, after the gun's trigger is pulled, a constant force acts on the bullet for the next 0.025 seconds until the bullet leaves the barrel of the gun with a speed of 992 m/s.
What is the change in momentum of the bullet?
The change in momentum of the bullet : 59.52 kg m/s
Further explanationGiven
m=0.06 kg
Δt=0.025 s
vo=0(from rest)
vt= 992 m/s
Required
The change in momentum
Solution
The change in momentum = ΔP
ΔP =m(vt-vo)
ΔP =0.06(992-0)
ΔP =59.52 kg m/s
A block of mass m is hung from the ceiling by the system of massless springs consisting of two layers. The upper layer consists of 3 strings in paralle, and the lower layer consists of 2 strings in parallel. The horizontal bar between the two layers has negligible mass. The force constants of all springs are k. Calculate the period of the vertical oscillations of the block.
Answer:
T₀ = 2π [tex]\sqrt{\frac{m}{k} }[/tex] T = [tex]\sqrt{\frac{5}{6} }[/tex] T₀
Explanation:
When the block is oscillating it forms a simple harmonic motion, which in the case of a spring and a mass has an angular velocity
w = [tex]\sqrt{k/m}[/tex]
To apply this formula to our case, let's look for the equivalent constant of the springs.
Let's start with the springs in parallels.
* the three springs in the upper part, when stretched, lengthen the same distance, therefore the total force is
F_total = F₁ + F₂ + F₃
the springs fulfill Hooke's law and indicate that the spring constant is the same for all three,
F_total = - k x - k x - kx = -3k x
therefore the equivalent constant for the combination of the springs at the top is
k₁ = 3 k
* the two springs at the bottom
following the same reasoning the force at the bottom is
F_total2 = - 2 k x
the equivalent constant at the bottom is
k₂ = 2 k
now let's work the two springs are equivalent that are in series
the top spring is stretched by an amount x₁ and the bottom spring is stretched x₂
x₂ = x -x₁
x₂ + x₁ = x
if we consider that the springs have no masses we can use Hooke's law
[tex]-\frac{F_{1} }{k_{1} } - \frac{F_{2}}{k_{2} } = \frac{F}{k_{eq} }[/tex]
therefore the equivalent constant is the series combination is
[tex]\frac{1}{k_{eq} } = \frac{1}{k_{1} } + \frac{1}{k_{2} }[/tex]
we substitute the values
\frac{1}{k_{eq} } = \frac{1}{3k } + \frac{1}{2k }
\frac{1}{k_{eq} } = \frac{5}{6k} }
k_eq = [tex]\frac{6k}{5}[/tex]
therefore the angular velocity is
w = [tex]\sqrt{\frac{6k}{5m} }[/tex]
angular velocity, frequency, and period are related
w = 2π f = 2π / T
T = 2π / w
T = 2π [tex]\sqrt{\frac{5m}{6k} }[/tex]
T₀ = 2π [tex]\sqrt{\frac{m}{k} }[/tex]
T = [tex]\sqrt{\frac{5}{6} }[/tex] T₀
If the angle between the net force and the displacement of an
object is greater than 90 degrees, then which option holds
true?
aThe object stops
b Kinetic energy decreases
C Kinetic energy increases
d Kinetic energy remains the same
Answer: kinetic energy decreases
Explanation:
When the angle between the net force and the displacement of an
object is greater than 90 degree, the Kinetic energy decreases.
The work done by a net force in moving an object over a given distance is given as;
[tex]W = F \times d \ cos(\theta)[/tex]
where;
θ is the angle between the net force and the displacementThe value of cos(θ) decreases from 0 to 180, consequently, the value of work-done will decrease as well.
Based on work-energy theorem, the work done on the object is equal to kinetic energy of the object.
[tex]W = K.E[/tex]
Thus, we can conclude that when the angle increases, the Kinetic energy decreases.
Learn more about kinetic energy here:https://brainly.com/question/10063455
why does the force of air resistance affect the motion of a person traveling at high speed more than a person walking across the room?
Answer:
yes .
Explanation:
...
;-; :) have a good day
Answer:
because on air the speed is high compared to walking
Determine the speed, wavelength, and frequency of light from a helium-neon laser as it travels through flourite. The wavelength of the light from the laser is 632.8 nm in air and the index of refraction of flourite is 1.434.
Answer and Explanation:
The computation is shown below:
As we know that
Frequency = Speed ÷ wavelength
= (3 × 10^8 )÷ (632.8 × 10^-9)
= 4.74 × 10^14 Hz
Speed in flourite is
= Vaccum speed ÷ refraction index
= 3 × 10^8 ÷ 1.434
= 2.092 × 10^8 m/s
wavelength is
= Speed in flourite ÷ frequency
= (3 × 10^8 × 632.8 × 10^-9) ÷ (1.434 × 3 × 10^8)
= 441.28nm
Do you know how to do this clever ones hmmm?? Describe and explain the motion of a small ball floating on a pond when waves travel across the pond.
Answer:
Ball moves up and down repeatedly on surface because waves consist of successive crests and troughs moving across surface, each crest pushes ball up and each trough allows it to move down.
Explanation:
A projectile is fired with a velocity of 8 m/s at an angle of 65º. What is the
vertical component of the velocity?
A. 6.5 m/s
B. 3.4 m/s
C. 10.2 m/s
D. 7.2 m/s
Answer:
i think its D
Explanation:
A 2 kg block is sitting motionless on a ramp at 24° with the horizontal. What is the force of friction on the block that resists its motion?
Answer:
7.97 N
Explanation:
[tex]f = m g sin(\alpha) = 2 * 9.8 * sin(24) = 7.97 N[/tex]
