Answer:
(a) 333.77 J
(b) 237.85 J
(c) 4763.77 J
(d) 4667.85 J
Explanation:
Temperature of source, TH = 314 K
Temperature of A, Tc = 292 K
Temperature of B, Tc' = 298 K
heat taken out, Qc = 4430 J
Let the heat deposited outside is QH and QH' by A and B respectively.
[tex]\frac{Q_H}{Q_c}=\frac{T_H}{T_c}\\\\Q_H = \frac{4430\times314}{292}=4763.77 J[/tex]
Now
[tex]\frac{Q_H'}{Q_c}=\frac{T_H}{T_c'}\\\\Q_H' = \frac{4430\times314}{298}=4667.85 J[/tex]
(a) Work done for A
W = QH - QC = 4763.77 - 4430 = 333.77 J
(b) Work done for B
W' = QH' - Qc = 4667.85 - 4430 = 237.85 J
(c) QH = 4763.77 J
(d) QH' = 4667.85 J
A spacecraft orbits the Earth at height of 1600km. Calculate the escape velocity for the spacecraft.
[G= 6.67×10^-11Nm^2kg^-2, mass of the Earth= 5.97×10^24kg, radius of the Earth= 6.37×10^6m]
Answer:
what do u need help with
Explanation:
Calculate the escape velocity for the spacecraft. [G= 6.67×10^-11Nm^2kg^-2, mass of the Earth= 5.97×10^24kg, radius of the Earth= ...
A ball is thrown vertically upward.It's velocity at the highest point is?
A. 10 ms^-1
B. Zero
C. 10 ms^-2
D. None of these
B
Explanation:
BECAUSE IT WAS GOING UPWORD THEN IT'S VELOCITY WAS DECREASING -10MS¹
Answer:
Explanation:
From physics, which is directly related to math (especially when it comes to parabolic motion!), we learn that at the very top of the parabola the object has to stop for a millisecond so it can turn around and fall back to earth. This translates to a velocity of 0 at its highest point. So B.
hai vật chuyển động ngược chiều qua A với B cùng lúc, ngược chiều để gặp nhau . Vật qua A có vận tốc 10m/s, qua B có vận tốc 15m/s. AB=100m
a, lấy trục tọa độ là đường thẳng AB, gốc tọa độ ở B , có chiều dương từ A sang B , gốc thời gian là lúc chúng cùng đi qua A và B . Lập phương trình chuyển động của hai xe
b, xác định vị trí , thời điểm 2 xe gặp nhau
c, xác định vị trí , thời điểm 2 xe cách nhau 25m
Answer:
wah wats this again
Explanation:
Bhai mujhe samaj nahi ah Raha
Kya Bolne Chahtaa hu tum
Answer:
bạn vẽ ra rồi làm
Explanation:
7. A thin wire was wound 30 times closely over a boiling tube. The total length of the windings as measured was found to be 6.3mm. Determine the diameter of the wire .
Answer:
Diameter of wire = 0.00021 meters
Explanation:
Given the following data;
Number of windings = 30
Length of windings = 6.3 mm to meters = 0.0063 meters
To find the diameter of the wire, we would use this mathematical expression;
Length of windings = number of windings * diameter of wire
Substituting the values into the expression, we have;
0.0063 = 30 * diameter of wire
Diameter of wire = 0.0063/30
Diameter of wire = 0.00021 meters
physics as a subject involves measurement and estimation,giving examples of everyday life situations, explain the meaning and what is done in each case
Answer:
57
Explanation:
what will be the effect on the acceleration due to gravity of the earth if it is compressed to a the size the moon?
Answer:
it gravitional pull on earth will increased becauste it is compress to a form of moon which is comperatively smaller so the gravitonal pull on per cm of earth will incrased so we can say that there will be change in acceleration due to gravity
valancy of an atom is +2. what does it mean.
Answer: I hope you find it useful
Explanation: Group 2 elements have two valence electrons. The two valence electrons are easily lost in the formation of chemical bonds. Once the two electrons are lost, the atom then has a full outer shell and is therefore more stable.
so, if an atom has valency 2 , then it means that the atom can combine with 2 other atoms .
magnetised hacksaw blade is cut into two pieces..can there be two poles on both sides??
Answer:
yes
Explanation:
because the dipoles are not arrange the same way they were in the full hacksaw
If the velocity of a motorcycle increases from 30 mis too 50m/s in 10 seconds what will be the acceleration of motorcycle?
Answer:
2 m/s^2
Explanation:
a = ∆v / ∆t
a = (50 - 30) / 10
a = 20 / 10
a = 2 m/s^2
acceleration = u-v/t
50-30/10
=2m/s
The hair dryer has a plastic case so there is no need for an earth wire connection in the plug ,explain why the hair dryer is still safe to use.
Answer:
plastics are unable to conduct electricity and heat due to there being no free flowing electrons, meaning they are safe to use.
Explanation:
state one similarity and one difference of sound of frequency 750Hz and ultrasound
Explanation:
Ultrasound refers to sound waves having frequencies greater than the frequency range limit. Ultrasound has the same physical qualities as "regular" (audible) music, except that individuals cannot hear it. Ultrasound devices use frequencies ranging from 20 kHz to a few gigahertz.
The frequencies of ultrasound utilised in clinical settings are generally between 2 and 12 MHz. Shorter wavelengths have a larger penetration depth into the body but less resolution; longer wavelengths have a greater depth of penetration but have a restricted depth of penetration.
An airplane flying at 116 m/s. E, is accelerated uniformly at the rate of 9.2 m/s2, E, for 13 s. What is its final velocity in m/s?
Answer:
235.6m/s
Explanation:
you have to use one of the kinematic formulas the best that suits the question given in this case you can use v=u+at.since the time, acceleration and initial velocity have been given in the question
v=116+(9.2)13^2
v=116+119.6
=235.6m/s
I hope this helps
A 6.0 kg mass is placed on a 20º incline which has a coefficient of friction of 0.15. What is the acceleration of the mass down the incline? show all work please
Answer:
Explanation:
The form of Newton's 2nd Law that we use for this is:
F - f = ma where F is the Force pulling the mass down the ramp forward, f is the friction trying to keep it from moving forward, m is the mass and a is the acceleration (and our unknown).
We know mass and we can find f, but we don't have F. But we can solve for that by rewriting our main equation to reflect F:
[tex]wsin\theta-\mu F_n=ma[/tex] That's everything we need.
w is weight: 6.0(9.8). Filling in:
6.0(9.8)sin20 - .15(6.0)(9.8) = 6.0a and
2.0 × 10¹ - 8.8 = 6.0a and
11 = 6.0a so
a = 1.8 m/s/s
From the description of the question, the acceleration is 1.95 ms-2.
What is friction?The term friction is defined a the force that seeks to prevent the movement of a surface on another.
Now we know that;
ma =mgsinθ - ukmgcosθ
ma =( 6 * 9.8 * sin 20) - ( 0.15 * 6 * 9.8 * cos 20)
a = ( 6 * 9.8 * sin 20) - ( 0.15 * 6 * 9.8 * cos 20) /6
a = 20 - 8.29/6
a = 1.95 ms-2
Learn more about acceleration: https://brainly.com/question/14356798
Electricity flows from
positive to positive
negative to positive
negative to negative
positive to negative
Answer:
is it from positive to negative am I right tell me if I am wrong
Answer:
positive to negative
The flow of electric current is similar to the flow of water which is from higher level to lower level.
The electric current flow from higher potential region(positive* low concentration of electron) to lower potential region(negative*high concentration of electron)
A rocket travels 1.3 km in 62 ms. What is its average speed in m⋅s−1? Do not give your answer in scientific notation. The answer should be given to 2 significant figures.
Answer:
Average speed = 0.35 m/s
Explanation:
Given the following data;
Distance = 1.3 Km
Time = 62 minutes
To find the average speed in m/s;
First of all, we would convert the quantities to their standard unit (S.I) of measurement;
Conversion:
1.3 kilometres to meters = 1.3 * 1000 = 1300 meters
For time;
1 minute = 60 seconds
62 minutes = X
Cross-multiplying, we have;
X = 62 * 60
X = 3720 seconds
Now, we can calculate the average speed in m/s using the formula;
[tex] Speed = \frac {distance}{time} [/tex]
[tex] Speed = \frac {1300}{3720} [/tex]
Average speed = 0.35 m/s
D=12000 m
T= 30min
V=?
Ayudenme en este ejercicio xfa
En m/min y en Km/h
what is the direction of magnetic lines of force outside the magnet
please mark me as brainiest p
Explanation:
Magnetic lines of force are closed curves. C) Outside the magnet their direction is from north pole to south pole and inside the magnet these are from south to north pole.
what can be done to increase speed of rotation of a DC motor
Answer: There are multiple options:
By varying the supply voltage.
By varying the flux, and by varying the current through the field winding.
By varying the armature voltage, and by varying the armature resistance.
Helpful Link:
https://www.elprocus.com/what-are-the-best-ways-to-control-the-speed-of-dc-motor/
A student project is required to be portable and hand held. It requires 6 V DC power at a current of 150 mA. The batteries for the power supply must last for a minimum of 7 hours of continuous operation. NiMH rechargeable batteries in AA size are to be used. A) How many batteries are needed
Answer:
a. 5 batteries b. 1050 mAh
Explanation:
Here is the complete question
A student project is required to be portable and hand held. It requires 6 V DC power at a current of 150 mA. The batteries for the power supply must last for a minimum of 7 hours of continuous operation. NiMH rechargeable batteries in AA size are to be used. A) How many batteries are needed? B) What mAh capacity should the batteries have?
Solution
A) How many batteries are needed?
Since the nominal voltage for a single NiMH battery is 1.2 V per battery and we require 6V DC power, we combine the batteries in series to obtain a total voltage of 6 V. The number of batteries required, n = total voltage/voltage per cell = 6V/1.2V per battery = 5 batteries
So, the number of batteries needed is 5.
B) What mAh capacity should the batteries have?
Since the batteries are in series, they would each deliver a current of 150 mA. Since we require a current of 150 mA for 7 hours, the number of milliampere-hours capacity mAh of batteries required is Q = It where I = current = 150 mA and t = time = 7 hours.
So, Q = It = 150 mA × 7 h = 1050 mAh.
So, the batteries should have a mAh of 1050 mAh
(This is for other people with this Question i hope you find this when you need help) Need answer for this Help!!!
Question 7 of 20 You plan to use a slingshot to launch a ball that has a mass of 0.025 kg. You want the ball to accelerate straight toward your target at 19 m/s2. How much force do you need to apply to the ball? O A. 19.03 N OB. 0.48 N O C. 4.51 N D. 760.00 N
Answer:
0.48N
Explanation:
according to the second law of motion
force=mass×acceleration
the mass in this question is 0.025,the acceleration 19
therefore f=0.025×19
=0.48N
I hope this helps
Explanation of the physics involved i the northern lights(aurora borealis) why can't it occur in mire southerns latitudes?
Answer:
The northern lights come from the interaction of electrically charged particles given off by the Sun surface during solar storms and the Earth's magnetic field which is pointed in the northern to southern poles of the Earth. Therefore, the charged particles that travel through millions of miles from the Sun to the Earth accelerate towards the magnetic poles and appear as the northern (and southern) lights
Boreal is an adjective word for the north or northern regions. In the southern latitudes, in the southern hemisphere, the phenomenon is called aurora australis (australis is the adjective for 'of the south')
Explanation:
Give reason Pascal is a derived unit
The pascal is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength.
Symbol ⇥ Pahai điện tích q1 =-2.10^(-8), q2=1,8.10^(-8) đặt tại A và B trong không khí,AB=8cm. Một điện tích q3 đặt tại C. 1, C ở đâu để q3 cân bằng
Answer:
Đáp án là vị trí để đặt q3 tại vị trí cân bằng là cách A một đoạn 0,0411 m
và nằm trong AB
Explanation:
Do q1 và q2 trái dấu nên q3 nằm trong
gọi r1 là vị trí từ A đến q3 suy ra r2=0.08-r1
Vị trí cân bằng nên [tex]\frac{q1}{r1^{2} }[/tex] = [tex]\frac{q2}{(0.08-r1)^{2} }[/tex]
8. What type(s) of motion do the particles in a solid undergo? A. vibrational, rotational, and translational B. vibrational and rotational C. vibrational only D. rotational only
Explanation:
Particles in solids are always vibrating (moving back and forth) in place.
A uniform, solid sphere of radius 2.50 cm and mass 4.75 kg starts with a purely translational speed of 3.00 m/s at the top of an inclined plane. The surface of the incline is 2.75 m long, and is tilted at an angle of 22.0∘ with respect to the horizontal. Assuming the sphere rolls without slipping down the incline, calculate the sphere's final translational speed v2 at the bottom of the ramp.
Answer:
The final translational seed at the bottom of the ramp is approximately 4.84 m/s
Explanation:
The given parameters are;
The radius of the sphere, R = 2.50 cm
The mass of the sphere, m = 4.75 kg
The translational speed at the top of the inclined plane, v = 3.00 m/s
The length of the inclined plane, l = 2.75 m
The angle at which the plane is tilted, θ = 22.0°
We have;
[tex]K_i[/tex] + [tex]U_i[/tex] = [tex]K_f[/tex] + [tex]U_f[/tex]
K = (1/2)×m×v²×(1 + I/(m·r²))
I = (2/5)·m·r²
K = (1/2)×m×v²×(1 + 2/5) = 7/10 × m×v²
U = m·g·h
h = l×sin(θ)
h = 2.75×sin(22.0°)
∴ 7/10×4.75×3.00² + 4.75×9.81×2.75×sin(22.0°) = 7/10 × 4.75×[tex]v_f[/tex]² + 0
7/10×4.75×3.00² + 4.75×9.81×2.75×sin(22.0°) ≈ 77.93
∴ 77.93 ≈ 7/10 × 4.75×[tex]v_f[/tex]²
[tex]v_f[/tex]² = 77.93/(7/10 × 4.75)
[tex]v_f[/tex] ≈ √(77.93/(7/10 × 4.75)) ≈ 4.84
The final translational seed at the bottom of the ramp, [tex]v_f[/tex] ≈ 4.84 m/s.
the diameter of circular park is 80 m find its area
A horse is running on a circular path with constant speed but its direction is changing at every point. It is
Answer:
accelerating.
Explanation:
A horse is running on a circular path with constant speed but its direction is changing at every point. Thus, it is accelerating.
Hydroplaning causes your front wheels to actually leave the pavement and the wheels are riding on a thin layer of water. This lack of traction with the pavement takes away your control of the vehicle. To regain control of your vehicle you should___________.
Answer: Remove your foot from the gas pedal and slow down
Explanation:
Hydroplaning also refers to aquaplaning and this refers to the scenario whereby there's a layer of water that builds between the tyres of a car and the surface of the road which then brings about a loss of traction which eventually leads to a situation whereby the car doesn't respond to control inputs.
This lack of traction with the pavement takes away your control of the vehicle and to regain control of the vehicle, one should remove your foot from the gas pedal and slow down.
What is use of lemon Squeezer
Answer:
A lemon squeezer is a small kitchen utensil designed to extract juice from lemons or other citrus fruit such as oranges, grapefruit, or lime. It is designed to separate and crush the pulp of the fruit in a way that is easy to operate.
Answer:
A lemon squeezer is a small kitchen utensil designed to extract juice from lemons or other citrus fruit such as oranges, grapefruit, or lime. It is designed to separate and crush the pulp of the fruit in a way that is easy to operate.
Explanation:
stay safe
Given that on Earth, gravity causes an acceleration of 9.8 m/s2, what is an acceleration of 7 g?
Answer:
68.6 m/s^2
Explanation:
1 g = 9.8 m/s^2
so
7 g × 9.8m/s^2 = 68.6