Answer:
Required energy Q = 231 J
Explanation:
Given:
Specific heat of copper C = 0.385 J/g°C
Mass m = 20 g
ΔT = (50 - 20)°C = 30 °C
Find:
Required energy
Computation:
Q = mCΔT
Q = 20(0.385)(30)
Required energy Q = 231 J
An 80-kg clown sits on a 20-kg bike on a tightrope attached between two trees. The center of mass of the clown is 1.6 m above the rope, and the center of mass of the bike is 0.70 m above the rope.
A) A load of what mass should be fixed onto the bike and hang 2.10 m below the rope so that the center of mass of the clown-bike-load system is 0.50 m below the rope?
B) What is the force that the rope exerts on each tree if the angle between the rope and the horizontal is 15 (degrees)?
Note: I have tried the center of mass formula Xcm= [(m1*x1) + (m2*x2) + (m3*x3)]/(m1+m2+m3) with no luck. Any help is much appreciated.
Answer:
Explanation:
the center of mass formula
Ycm= [(m₁y₁) + (m₂y₂) + (m₃y₃)] / (m₁+m₂+m₃)
Rope forms the x axis and position of centre of different massses are above or below it so they represent their location on y - axis.
y₁ = 1.6 , y₂ = .7 and y₃ = - 2.1
Ycm ( given ) = - .5
Putting the values of masses and positions
- .5 = 80 x 1.6 + 20 x .7 + m₃ x - 2.1 / ( 80 + 20 + m₃ )
- .5 = 128 + 14 + m₃ x - 2.1 / ( 100+ m₃ )
- 50 - .5 m₃ = 142 - 2.1 m₃
1.6 m₃ = 192
m₃ = 120 kg .
B )
Total downward force is weight of total mass = 80 + 20 + 120
= 220 kg
weight = 220 x 9.8 = 2156 N .
component of weight perpendicular to rope
= 2156 cos 15 = 2082.53 N
This force will be equally distributed over each tree , so force on each tree = 2082.53 / 2 = 1041.26 N .
which newton's laws applies to a slinky?
PLEASE HELP !!
When a Slinky sits atop a staircase, gravity acts on the toy, keeping it still. Knock over the Slinky, and Newton's second law comes into play. As middle school physics class may have taught you, this law states that providing force to an object increases its acceleration.
hopes this helps uh ❣
Answer:
We know from Newton's First Law of motion that an object at rest stays at rest unless acted upon by an external force. So in the case of the slinky, that is exactly why the bottom of the slinky does not move.
Explanation:
Help please ! Ill give brainliest !! ☁️✨
Imagine visitors moving into and out of an art gallery as a model of a
chemical reaction at equilibrium. Which situation represents a system in
dynamic equilibrium?
O A. Some visitors stay for a long time, while others go back outside
quickly
B. Visitors enter the art gallery at the same rate as other visitors
leave.
C. Some visitors stand looking at one painting for a long time, while
others move quickly past the paintings and go outside again.
D. No visitors enter or leave the art gallery.
Option B. Visitors enter the art gallery at the same rate as other visitors leave.
Answer:
B) Visitors enter the art gallery at the same rate as other visitors
leave.
Explanation:
A.P.E.X
Please help me I’ll mark brainless
Answer:
ITS B NOT A
Explanation:
Newton's law of cooling states that the temperature of an object changes at a rate proportional to the difference between its temperature and that of its surroundings. Suppose that the temperature of a cup of coffee obeys Newton's law of cooling. If the coffee has a temperature of 205 degrees Fahrenheit when freshly poured, and 2.5 minutes later has cooled to 195 degrees in a room at 70 degrees, determine when the coffee reaches a temperature of 160 degrees.
Answer:
Tt = 70 + 135e^-0.031t
13 minutes
Explanation:
Given that :
Initial temperature, Ti = 205°
Temperature after 2.5 minutes = 195°
Temperature of room, Ts= 70
Using the relation :
Tt = Ts + Ce^-kt
Temperature after time, t
When freshly poured, t = 0
205 = 70 + Ce^-0k
205 = 70 + C
C = 205 - 70 = 135°
T after 2.5 minutes to find proportionality constant, k
Tt = Ts + Ce^-kt
195 = 70 + 135e^-2.5k
125 = 135e^-2.5k
125 / 135 = e^-2.5k
0.9259 = e^-2.5k
Take In of both sides :
−0.076989 = - 2.5k
k = −0.076989 / - 2.5
k = 0.031
Equation becomes :
Tt = 70 + 135e^-0.031t
t when Tt = 160
160 = 70 + 135e^-0.031k
90 = 135e^-0.031t
90/135 = e^-0.031t
0.6667 = e^-0.031t
In(0.6667) = - 0.031t
−0.405465 = - 0.031t
t = 0.405465/ 0.031
t = 13.071
t = 13 minutes
A trough is 7 meters long, 2 meters wide, and 1 meters deep. The vertical cross-section of the trough parallel to an end is shaped like an isoceles triangle (with height 1 meters, and base, on top, of length 2 meters). The trough is full of water (density 1000 kg m 3 ). Find the amount of work in joules required to empty the trough by pumping the water over the top. (Note: Use g
Answer:
68600Nm
Explanation:
Given that:
Lenght, L = 7
Width, W = 2
Depth, d = 1
Triangle = with height 1 meters, and base, on top, of length 2 meters
Area of triangle = 0.5 * base * height
Area of triangle = 0.5 * 2 * 1 = 1m²
Volume = area * length
Volume = 1m² * 7m
Volume = 7m³
Weight of water = Volume * density * g
g = acceleration due to gravity
Density of water , d = 1000kg/m³
Weight = 7m³ * 1000kg/m³ * 9.8m/s²
Weight = 68,600 Kgm/s² = 68600 N
Workdone = Force * distance = weight * depth
Workdone = 68600N * 1m
Workdone = 68600Nm
Solving steps and answer!
Answer:
162 cm
Explanation:
We are told that the Body surface are of a patient is given by the formula;
BSA = (√wh)/60
Where;
w is weight in kg
h is height in cm
We ware now given that;
w = 50 kg
BSA = 1.5
Thus;
1.5 = (√50h)/60
Multiply both sides by 60 to get;
90 = (√50h)
Square both sides to get;
90² = 50h
h = 90²/50
h = 162 cm
17. During a game of tug of war, two teams of students pull on opposite sides of a rope. During the
game, the rope begins to accelerate towards the left. What must be true about the forces acting on the
rope at the time of the acceleration towards the left?
A. The team pulling towards the right is pulling with a force greater than the team pulling towards the left.
B. The team pulling towards the right is pulling with a force equal to the team pulling towards the left.
C. The team pulling towards the right is pulling with a force less than the team pulling towards the left.
D. The team pulling towards the right stopped pulling the rope while the team pulling towards the left
continued
Answer:
c
Explanation:
The Moon has a smaller mass than the Earth. If you were to travel to the moon your weight would....
A Increase
B Decrease
C Stay the Same
D Vary with day and night
Answer:The Moon has a smaller mass than the Earth. If you were to travel to the moon your weight would..
Explanation: It would decrease.
The Moon has a smaller mass than the Earth. If you were to travel to the moon your weight would decrease because the acceleration due by gravity on the moon is less than the acceleration due to gravity on the earth, therefore the correct answer is option C.
What is gravity?It can be defined as the force by which a body attracts another body towards its center as the result of the gravitational pull of one body and another.
In comparison to the Earth, the Moon is less massive. Your weight would drop if you traveled to the moon because the acceleration caused by gravity there is lower than that caused by gravity here on Earth.
As a result of the less gravity on the moon, the weight would decrease.
Thus, the correct answer is option C.
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This is from P.E , que some please help me
Answer:
I know that 2 is called a foul I dont know about 1 though
which particles do not affect the stability of the atom
Electrons are the particle pr4esent inside the atom that does not affect the stability of the atom,
What is radioactivity?The ability of some unstable atoms to emit nuclear radiation spontaneously, typically in the form of alpha or beta particles frequently accompanied by gamma rays, is known as radioactivity.
An overabundance of neutrons or protons can make the nucleus of an atom unstable.
A radioactivity atom will try to become stable by extruding other particles, such as protons or neutrons, or by releasing energy in various ways.
Thus, Electrons are the particle present inside the atom that does not affect the stability of the atom,
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Which of the following sentences is an example concerns smerne might have at lunchtime?
I would be to have brocoll stead of fres,
I wonder if my chicken is ooked all the way
I have never ordered smething I did not ke,
of ordered a salad with the dressing on the site
Answer:
yes
Explanation:
becausw yesnssjsdkwww
Pluto has a radius of 1.15 x 10^6 m, and its acceleration due to gravity is 0.61 | m/s^2. What is Pluto's mass?
so we will use Newton's gravitational law :
gravitational acceleration = G*m/r^2
G is the gravitational constant = G = 6.673×10^-11 N m^2 kg^-2
after substitution :
6.673×10^-11 * m / (1.15 x 10^6)^2 = 0.61
= 5.04575*10^-23 * m = 0.61
dividing over 5.04575*10^-23 :
m = 1.20894*10^22 kg
pls give me brainliest
If someone walkes 1000m
in 20min, what is their speed?
Answer:
Distance - 1000m
Time - 20min
Speed - ?
Use the formula of distance ÷ time = speed.
s = d/t
s = 1000m/20min
s = 50 m/min
Hope this helps, thank you !!
A 0.75 kg golf ball is being launched from the ground. What is its potential energy
Explanation:
the question it's not complete as I don't know the height as the formula for potential energy is : PE = mgh
(m) - mass acceleration due to gravity
(g) - acceleration due to gravity (9.8 m/s2)
(h) - height
A football of mass 2.5kg is lifted up to the top of a cliff that is 180m high. How much
potential energy does the football gain?
The potential energy of the football with mass 2.5 kg which is lifted up to the top of a cliff is 4410 Joules.
What is Potential energy?Potential energy is the stored energy which depends upon the relative position of the various parts of a system of objects. Potential energy is the product of mass of the object, acceleration due to gravity, and the height. The SI unit of potential energy is Joule (J).
PE = m × g × h
PE = Potential energy,
m = mass of the object,
g = acceleration due to gravity,
h = height
PE = 2.5 × 9.8 × 180
PE = 4410 Joules
Therefore, the potential energy of the football is 4410 Joules.
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Two ice skaters approach each other at right angles. Skater A has a mass of 68.2 kg and travels in the x direction at 2.48 m/s. Skater B has a mass of 34.4 kg and is moving in the y direction at 1.18 m/s. They collide and cling together. Find the final speed of the couple. Answer in units of m/s.
Answer:
1.70 m/s
Explanation:
The computation of the final speed of the couple is shown below:
initial momentum of A is
= mv
= 68.2 × 2.48
= 169.136 kg
And, the initial momentum of B is
= mv
= 34.4 × 1.18
= 40.592 kg
Now magnitude is
= sqrt( A^2 + B^2)
= sqrt( 28,606.99 + 1,647.71)
= 173.94
Now the final speed is
= 173.94 ÷ (68.2 + 34.4)
= 1.70 m/s
A transformer has 1500 turns on the primary coil and 30 000 turns on the secondary coil. What is the potential difference across the secondary coil, if the primary coil has a potential difference of 20 000V?
please help :/
Answer:
turle
Explanation:
The plates of a parallel plate capacitor each have an area of 0.40 m2 and are separated by a distance of 0.02 m. They are charged until the potential difference between the plates is 3000 V. The charged capacitor is then isolated. Determine the magnitude of the electric field between the capacitor plates.
Answer:
E = -1.5 10⁵ N / C
Explanation:
In a capacitor the electric field is uniform between the blades, therefore we use the expression
V = - E s
E = - V / s
let's calculate
E = - 3000 / 0.02
E = -1.5 10⁵ N / C
the sign indicates that the field and the potential are opposite, when one increases the gold decreases
A car starts from rest and accelerates uniformly at a rate of 2.0 meter per second squared for 4.0 seconds. During this time interval, the car traveled ________ meters.
Answer:
16
Explanation:
[tex] \frac{1}{2} \times 2 \times {4}^{2} = 16[/tex]
What simple machine can best be described as "a simple machine that uses an inclined plane wrapped around a rod"?
a wedge
a screw
a wheel and axle
a lever
Answer:
It is a screw.
Explanation:
A hiker walks 11 km due north from camp and then turns and walks due east. The
total distance walked is 22 km. How far due east did the hiker walk?
Answer:
Thats probably 11
Explanation:
What is the period, in seconds, that corresponds to each of
the following frequencies: (a) 10 Hz, (b) 0.2 Hz, (c) 60 Hz?
Answer:
0.1s,5s,0.017s
Explanation:
T=1÷frequency
Answer:
a =
✔ 6
The period is
✔ 2 seconds.
b =
✔ pi
Explanation:
Graph the function using the graphing calculator. Find the least positive value of t at which the pendulum is in the center.
t =
✔0.5 sec
To the nearest thousandth, find the position of the pendulum when t = 4.25 sec.
d =
✔ 4.243 in.
At what latitude are there almost no differences between the seasons? Explain
why this occurs?
Answer:
The four-season year is typical only in the mid-latitudes. The mid-latitudes are places that are neither near the poles nor near the Equator. The farther north you go, the bigger the differences in the seasons.
Explanation:
hope this helps have a good day :) ❤
At a latitude equal to zero degrees there is little seasonal variation. This phenomenon is due each day the Sun's rays strike the Earth's surface at approximately the same angle near the Equator.
The Equator is the line of 0° (zero degrees) latitude around the middle of the Earth.
Moroever, the intensity of solar radiation and therefore also the temperature at the Earth's surface largely depends on the angle of incidence of the Sun's rays.
At 0° latitude, there is a very little seasonal variation because all days the Sun's rays strike the Earth's surface at approximately the same angle. At the Equator, the Sun's rays strike the Earth's surface at an angle of 90°, causing warmer temperatures compared to higher latitudes.
In additon, at 0° latitude, all days also have the same number of hours of light and dark (i.e., approximately 12 hours of sunlight).
In conclusion, at a latitude equal to zero degrees (i.e., at the Equator) there is little seasonal variation. This phenomenon is due each day the Sun's rays strike the Earth's surface at approximately the same angle near the Equator.
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Can Magnetic poles effects each other
Answer:
Explanation:
But the reality is that: Multiple magnetic fields would fight each other. This could weaken Earth's protective magnetic field by up to 90% during a polar flip. Earth's magnetic field is what shields us from harmful space radiation which can damage cells, cause cancer, and fry electronic circuits and electrical grids.
How do magnetic poles interact? Magnetic poles that are alike repel each other, and magnetic poles that are unlike attract each other. The area of magnetic force around a magnet. The magnetic field lines spread out from the north pole, curve around, and return to the south pole.
When two magnets are brought together, the opposite poles will attract one another, but the like poles will repel one another. This is similar to electric charges. The earth is like a giant magnet, but unlike two free hanging magnets, the north pole of a magnet is attracted to the north pole of the earth.
Magnetic forces are non contact forces; they pull or push on objects without touching them. Magnets are only attracted to a few 'magnetic' metals and not all matter. Magnets are attracted to and repel other magnets.
(hope this helps can i plz have brainlist :D hehe)
T Or F- True or False There three types of cloud's are .
Answer:
There are three main cloud types.
The foundation consists of 10 major cloud types. In addition to cirrus, stratus, cumulus, and nimbus clouds, there are cirrostratus, cirrocumulus, altostratus, altocumulus, stratocumulus, nimbostratus, and cumulonimbus clouds. The following table places these cloud types into the four major cloud groups.
Explanation:
So false, depends what you have learned and your grade level ig
A weightlifter holds a 1,500 N barbell 1 meter above the ground. One end of a 2-meter-long chain hangs from the center of the barbell. The chain has a total weight of 400 N. How much work (in J) is required to lift the barbell to a height of 2 m
Answer:
1800 J
Explanation:
We are given that
Weightlifter hold weight, w=1500N
Height of weightlifter from ground,h=1m
Length of chain=2m
Total weight of chain, w'=400 N
We have to find the work done required to lift the barbell to height of 2m.
Total work done=Work done to lift a barbell and half of the chain+ work done to lift the upper half of the chain
Total work done=[tex]1500+\frac{1}{2}(400)+\frac{1}{2}(400)(\frac{1}{2}(1))[/tex]
Total work done=[tex]1700+100[/tex]
Total work done=1800 J
Hence, work done is required to lift the barbell to a height of 2 m=1800 J
A 70 kg Throckmorton was riding his skateboard when a small, but juicy 0.001 kg beetle hits the front of his helmet, splattering, obstructing his view. Who experienced the greatest change in momentum?
Answer:
The beetle
Explanation:
The beetle is correct because of the the force of the Throckmortan was a lot heavier and thus making the beetle feel the force.
Momentum before = momentum after
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
(70.0 kg) (3.0 m/s) + (2.0 kg) (3.0 m/s) = (70.0 kg) (3.1 m/s) + (2.0 kg) v
210 kg m/s + 6 kg m/s = 217 kg m/s + (2.0 kg) v
-1 kg m/s = (2.0 kg) v
v = -0.5 m/s
The skateboard's velocity is 0.5 m/s west. Hope I helped and have a good day!
________________________________________________________
前の勢い=後の勢い
m₁u₁+m₂u₂=m₁v₁+m₂v₂
（70.0 kg）（3.0 m / s）+（2.0 kg）（3.0 m / s）=（70.0 kg）（3.1 m / s）+（2.0 kg）v
210 kg m / s + 6 kg m / s = 217 kg m / s +（2.0 kg）v
-1 kg m / s =（2.0 kg）v
v = -0.5 m / s
スケートボードの速度は西に0.5m / sです。私が助けて、良い一日を過ごせることを願っています！
Which of the following is a physical quantity that has a magnitude but not
direction?
- vector
- frame of reference
- scalar
- resultant
Answer:
Scalar
Explanation:
A scalar quantity is a physical quantity that has magnitude but no directional attribute.
An example of a scalar is speed and distance.
A vector is a physical quantity that has both magnitude and direction.
An example is displacement and velocity.
Scalar has only the magnitude value specified and nothing else.
