Answer:
Explanation:
Here,
Final mass(m)=150g
Final Temperature(t)=60°C
Temperature of hot water(t1)=90C
Temperature of cold water(t2)=14C
Let the grams of water to be used per face be m1 grams and (150-m1) grams for hot and cold water respectively.
We know that,
Heat lost by hot body=Heat gained by cold body
or, m1 s1 Δt1=m2 s2 Δt2
or, m1 (t1-t)=(150-m1) (t-t2) [∵s1=s2, SHC of water is taken to be same]
or, m1 (90-60)=(150-m1) (60-14)
or, 30m1=6900-46m1
or, 76m1=6900
∴m1=90.79g
(150-m1)=59.21g
Hence, 90.79g and 59.21 g hot and cold water must be used respectively.
Straight wire of indefinite length (transient) passed by an electric current of 5.0 A. The magnetic field generated around this conductor at point M is 50 μT. Thus the distance from the conductor to point M is:
A. 2π cm
B. 0.2π cm
C. 2.0 cm
D. 0.20 cm
Answer:
C. 2.0 cm
Explanation:
The magnetic field around the wire at point M is given by Biot-Savart Law:
[tex]B = \frac{\mu_o I}{2\pi R}[/tex]
where,
B = Magnetic field = 50 μT = 5 x 10⁻⁵ T
I = current = 5 A
μ₀ = permeability of free space = 4π x 10⁻⁷ N/A²
R = distance of point M from wire = ?
Therefore,
[tex]5\ x\ 10^{-5}\ T = \frac{(4\pi\ x\ 10^{-7}\ N/A^2)(5\ A)}{2\pi R}\\\\R = \frac{(2\ x\ 10^{-7}\ N/A^2)(5\ A)}{5\ x\ 10^{-5}\ T}\\[/tex]
R = 0.02 m = 2 cm
Hence, the correct option is:
C. 2.0 cm
A car is running uniformly with the velocity of 72km/h3, what is its acceleration?
Answer: a =0
Explanation:
What the velocity from the graph given above?
Answer:
i think its 4 or 35
Explanation:
its in the middle of 40 and 30
5. Can you get the machine with efficiency 100% in practice? Why?
Answer:
No,
Explanation:
Efficiency of a machine is always less than 100% as output energy is always less than the input energy, because some energy is lost to overcome friction.
(a) What kind of energy is possessed by an aeroplane flying at a height of 10000 m?
Answer:
When the plane is rest position it possess potential energy. But when a aeroplane is flying at the height it possess kinetic energy. No matter what height is given.
A certain superconducting magnet in the form of a solenoid of length 0.28 m can generate a magnetic field of 7.0 T in its core when its coils carry a current of 80 A. The windings, made of a niobium-titanium alloy, must be cooled to 4.2 K. Find the number of turns in the solenoid.
Answer:
The number of turns in the solenoid is 19506.
Explanation:
Length of solenoid, L = 0.28 m
Magnetic field, B = 7 T
Current, I = 80 A
Let the number of turns is N.
The formula used to find the magnetic field is
[tex]B = \frac{\mu 0N I}{L}\\\\7 = \frac{4 \times 3.14\times 10^{-7}\times N\times 80}{0.28}\\\\N = 19506[/tex]
a teacher and two students are mesuring the speed of sound. the teacher makes loud sound by hitting two cymbals together. each students starts a stopwatch then they see the teacher hit the cymbals, they each stop their stop watch when they hear the sound. describe how a sound wave moves through the air.
Answer:
Slowly and smoothly lol
Answer:
S.I. on Rs. 1600 = T.D. on Rs. 1680. Rs. 1600 is the P.W. of Rs. 1680, i.e., Rs. 80 is on Rs. 1600 at 15%. Time =100 x 80year=1year = 4 months.1600 x 153
Explanation:
Is this you are?
Which statement about the ocean is true?
No evaporation or precipitation in the water cycle occurs over the ocean.
Most evaporation and precipitation in the water cycle occur over the ocean.
All evaporation and precipitation in the water cycle occur over the ocean.
Evaporation, but not precipitation, in the water cycle occurs over the ocean.
Answer:
most evaporation and precipitation in the water cycle occus over the ocean
The option Most evaporation and precipitation in the water cycle occur over the ocean. is the correct answer
Give reason.
b} String roller is an example of wheel and axel .Why?
Explanation:
string roller is called an example of wheel and axel because The thin rod which needs to be turned is called the axle and the wider object fixed to the axle, on which we apply force is called the wheel.
hence the we apply force on the roller and the string gets tight.
Which of the following is occurring while a satellite is in orbit around Earth? O It is continuously pulling away from Earth It is continuously falling toward the surface of Earth. It stays in a constant speed orbit where it was oriented from the start. It stays in the same orbit orientation traveling at variable speeds.
AnswerIt is continuously falling towards the surface of the earth
Explanation:
since gravity from earth is the thing that keeps it constantly in orbit
What will happen to the velocity and momentum of each ball when the small ball hits the heavier large ball?
The small ball will transfer its momentum to the heavier ball. Since the momentum gets conserved. The velocity will depend upon the mass of the balls.
What is the law of conservation of momentum?According to the law of conservation of momentum. The momentum of the body before the collision is always equal to the momentum of the body after the collision.
The momentum of the body is given by the product of the mass and velocity of the body.
According to the law of conservation of momentum
Momentum before collision =Momentum after collision
Hence the small ball will transfer its momentum to the heavier ball.
To learn more about the law of conservation of momentum refer;
https://brainly.com/question/1113396
A toy car with a mass of 5.5 kg is moving horizontally over flat ground at a speed of 2.1 m/s. An unknown force then directly pushes the car for a distance of 3 meters, after which the car has a speed of 7.3 m/s. You may assume that air resistance and friction are both negligible. What was the magnitude of the unknown force
Answer:
The magnitude of the unknown force is 44.8 N.
Explanation:
The force can be found with Newton's second law:
[tex] F = ma [/tex]
Where:
m: is the mass of the toy car = 5.5 kg
a: is the acceleration
F: is the force =?
We can calculate the acceleration with the following kinematic equation:
[tex] v_{f}^{2} = v_{0}^{2} + 2ad [/tex]
Where:
[tex] v_{f} [/tex]: is the final speed = 7.3 m/s
[tex] v_{0} [/tex]: is the initial speed = 2.1 m/s
d: is the distance traveled = 3 m
Hence, the acceleration is:
[tex] a = \frac{v_{f}^{2} - v_{0}^{2}}{2d} = \frac{(7.3 m/s)^{2} - (2.1 m/s)^{2}}{2*3 m} = 8.15 m/s^{2} [/tex]
Finally, the magnitude of the force is:
[tex]F = ma = 5.5 kg*8.15 m/s^{2} = 44.8 N[/tex]
Therefore, the magnitude of the unknown force is 44.8 N.
I hope it helps you!
(6). A car travels in a straight line from city A to city B at a speed of 60kmh-1
. Then return
from city B to city A along the original route at a speed of 40kmh-1
. The distance between
the two cities is 120 km. What is the average speed of the vehicle?
1. 30kmh-1
2. 45kmh-1
3. 48kmh-1
4. 60kmh-1
Please help (I didn’t know what subject to put this in but it’s earth science)
the unit of force and pressure are called derived unit
Answer:
yes
Explanation:
because they can be derived in the form of base units
Explain the effects of force giving example
Answer:
1) Can change the state of an object(rest to motion/ motion to rest):For example, pushing a heavy stone in order to move it. 2) May change the speed of an object if it is already moving. 4) May bring about a change in the shape of an object. For example, blowing air in balloon.
Explanation:
Effect of force Can change the state of an object(rest to motion/ motion to rest):For example, pushing a heavy stone in order to move it.
A person carries a box of 100 kg. What is the weight of the box? (g= 9.8 m/s2)
Answer:
980 newton
Explanation:
100×9.8 = 980
The needle in the following diagram rotates around a fixed point in the middle. Based on the information given, what way will the needle rotate when the current is applied?
Answer:
nods 40th anniversary rid off e 49en9 snns
in a cathode-ray tube, particles are fired at the screen. What are these particles
In isoelectric focusing gel electrophoresis a. there is a pH gradient that parallels the electric field gradient b. particular care must be taken to ensure the same pH along the length of the gel c. the electric current is allowed to fluctuate d. the electric circuits of the apparatus must be very well insulated
Answer:
a. there is a pH gradient that parallels the electric field gradient.
Explanation:
Gel electrophoresis is a technique used to separate DNA fragments according to their size. DNA samples are loaded in the wells and then electric current is applied to pull the DNA fragments out from the gel. Isoelectric gel electrophoresis is a process in which negatively charged DNA fragments are separated from the gel.
7) A ball is thrown upward at an initial velocity of 8.2 m/s, from a height of 1.8 meters above the ground. The height of the ball h, in metres can be represented, after t seconds, is modelled by the equation h = –4.8t² + 8.2t + 1.8. (a) Determine the height of the ball after 1.7 seconds.
[tex] \\ \tt \longmapsto \: h = - 4.8 {t}^{2} + 8.2t + 1.8 \\ \\ \tt \longmapsto \: h = - 4.8(1.7) {}^{2} + 8.2 \times 1.7 + 1.8 \\ \\ \tt \longmapsto \: - 4.8 \times 2.89 + 1.39 + 1.8 \\ \\ \tt \longmapsto \: 13.8 + 1.39 + 1.8 \\ \\ \tt \longmapsto \: 17.06[/tex]
express in standard form
(I)0.000038
Answer:
3.8 x 10^-5
Explanation:
all you doing is putting it in the standard form I hope this help
La resistencia de un termómetro de platino es de 6Ω a30°C. Hallar su valor correspondiente a 100°C,sabiendo que el coeficiente de temperatura de resistividad del platino vale 0,00392°C^(-1).
Respuesta:
7,6 Ω
Explicación:
Paso 1: Información dada
Resistencia a 30 °C (R₀): 6 ΩCoeficiente de temperatura (α): 0,00392 °C⁻¹Paso 2: Hallar la resistencia (R) a 100 °C
Podemos ver la relación entre la resistencia de un material y la temperatura usando la siguiente ecuación.
R = R₀ (1 + α × ΔT)
R = 6 Ω (1 + 0,00392 °C⁻¹ × (100 °C - 30 °C)) = 7,6 Ω
A bullet of mass of 50g is moving with the velocity of 200km/h .calculate the kinetic energy of the bullet .
Answer:
is 10³
Explanation:
cuz the formula of KE is 1/2mv²
covert 50g to kg first then plug in the formula
1/2 × 0.05 × 200 = 10³ J
A 45.0 kg student runs at a constant velocity up the incline 6 metres high. If the power output of the student is 1.50 x 103 W, how long does it take the student to run the 9.0 m along the incline?
Answer:
The time taken is 1.76 s.
Explanation:
mass of student, m = 45 kg
height, h = 6 m
power, P = 1500 W
Power is defined as the rate of doing work.
Work done in moving height is
W = m g h
Let the time is t.
P = m g h / t
1500 = 45 x 9.8 x 6 / t
t = 1.76 s
how do atoms lose electrons ?
Answer:
Explanation:
By being close to an atom that will gladly take the electrons being offered.
Suppose you are talking about Be. It is in the second column. It has two outer electrons that can be given away. It will not give away one of the two remaining electrons because they are too close to the + nucleus.
Along comes a Fluorine atom. It has 7 electrons in its outer ring. The chemistry of the situation allows it to take on one of the two electrons Be is offering. It is all a matter of charges and attractions.
Another Fluorine atom will take on the remaining electron from the Be. The outer ring cannot take on more than 1 electron, but that is enough
(Q008) Magnetic anomalies are a. found only on the seafloor. b. measured with an instrument called an inclinometer. c. defined as the angle between which a compass needle points and the longitude at that point. d. places where the magnetic field strength is either greater or less than the expected strength.
Answer: D. places where the magnetic field strength is either greater or less than the expected strength.
Explanation:
Magnetic anomaly refers to the change in the magnitude of the magnetic field of the Eatth with respect to the location's expected value.
Magnetic anomalies are places where the magnetic field strength is either greater or less than the expected strength. Therefore, the correct option is D.
what is efficiency of a machine?
Answer:
Efficiency of a machine is defined as the ratio of output work to input work in a machine . It is expressed in percentage and denoted by
η ( eta).
Describe the term of inertia with the respect of motion
Answer:
Inertia can be defined as the tendency of an object or a body to continue in its state of motion or remain at rest unless acted upon by an external force.
Explanation:
Motion can be defined as a change in the location (position) of a physical object or body with respect to a reference point.
This ultimately implies that, motion would occur as a result of a change in location (position) of an object with respect to a reference point or frame of reference i.e where it was standing before the effect of an external force.
Inertia can be defined as the tendency of an object or a body to continue in its state of motion or remain at rest unless acted upon by an external force.
Newton's First Law of Motion is also known as Law of Inertia and it states that, an object or a physical body in motion will continue in its state of motion at continuous velocity (the same speed and direction) or, if at rest, will remain at rest unless acted upon by an external force.
The inertia of an object such as a truck is greatly dependent or influenced by its mass; the higher quantity of matter in a trailer, the greater will be its tendency to continuously remain at rest.
In conclusion, inertia is applicable to all physical objects.
How can you say gravitational force is a field force
Answer:
because gravity pulled us in the land if there is no gravitational force there will not be field force too
Explanation:
hope it's will help you
