Answer: there are 15 coins of $2 and 18 coins of $5
Explanation:
I will answer in English.
X is the number of $5 coins.
Y is the number of $2 coins.
We have the system of equations:
Y + X = 33
Y*2 + X*5 = 120
first, we must isolate one of the variables in one of the equations and then replace it in the other equation, let's isolate Y in the first equation:
Y = 33 - X.
Then we can replace it in the other equation:
(33 - X)*2 + X*5 = 120
66 - X*2 + X*5 = 120
X*3 = 54
X = 54/3 = 18
and using the equation for Y.
Y = 33 - X = 33 - 18 = 15
So there are 15 coins of $2 and 18 coins of $5
What is the magnitude of the magnetic field created 4.0m away from a 10.0 A current?
Answer:
The magnitude of the magnetic field created is 5 x 10⁻⁷ T
Explanation:
Given;
magnitude of current, I = 10.0 A
distance of the magnetic field, r = 4.0m
Apply Biot-Savart Law to determine the magnitude of of the magnetic field created;
[tex]B = \frac{\mu_oI}{2 \pi r}[/tex]
where;
B is the magnitude of of the magnetic field
μ₀ is constant
I is current
r is the distance of the field
[tex]B = \frac{4 \pi*10^{-7} *10}{2 \pi*4} = 5*10^{-7} \ T[/tex]
Therefore, the magnitude of the magnetic field created is 5 x 10⁻⁷ T
A man takes a brick out of the fire when it's at 285 degree Celsius,he drops it in a bucket of water.then covers the bucket.the bucket and cover are made of an insulating material.the bucket contains 2.6 kg of ice originally at -5 degree celsius.the 1.3 kg brick is made of iron .which has a specific heat of 448J/kg degree celsius.lets find out the temperature of brick and water once equilibrium is reached.specific heats of ice , liquid water,steam are 2090,4186,1970 respectively
Answer: The equilibrium temperature of brick and water is 2.82 Kelvin
Explanation:
Initial Temperature Ø of the brick = 285 degree Celsius
Initial temperature of ice = - 5 degree Celsius
Mass of iron = 1.3kg
Specific heat capacity c of iron = 448J/kg
In thermal experiments,
Heat lost = heat gain.
Let's first calculate the heat lost
The brick will loose heat.
H =mcØ
Heat lost = 1.3 × 448 × (285 - T)
Heat lost = 582.4( 285 - T )
Now let's calculate for heat gain
Heat gain = mcØ + mcØ + mcØ
Heat gain = [(2.6×2090) + (2.6×4186) + (2.6×1970)](T - -5)
Heat gain = 5434 + 10883.6 + 5122(T+5)
Heat gain = 21439.6( T + 5)
Equating the heat lost and the heat gain leads to
582.4( 285 - T) = 21439.6(T+5)
Open both bracket
165984 - 582.4T = 21439.6T + 107198
Collect the like terms
21439.6T - 582.4T = 165984 - 107198
20857.2T = 58786
T = 58786/20857.2
T = 2.82 Kelvins
The equilibrium temperature of brick and water is 2.82 Kelvin
Two trains run in the same direction. The one behind has double the length of the one ahead. The initial distance of separation = 200 m. The speeds are(a) train in front = 36 km/h(b) train behind = 108 km/h. If it took 40 seconds for the longer train to overtake the shorter one , find the length of the shorter train.
Answer:
The shorter train has a length of 600m
Explanation:
The equation of motion of the first train can be written as:
[tex]x'=v't[/tex] (1)
v' = 108km/h = 30m/s
Furthermore, you can write the equation of motion of the second train as:
[tex]x=(200+l)+vt[/tex] = xo + vt (2)
v = 36km/h = 10m/s
where you have taken the initial position as measured from the front of the first train to the front of the second one. l is the length of the second train and 200 the separation of it respect to the first train.
For t = 40 both trains have the same position, that is, x=x'. Then, you equal equations (1) and (2), replace t=40, and solve the equation for l:
[tex]x'=x\\\\v't=200+l+vt\\\\(30m/s)(40s)=200+l+(10m/s)(40s)\\\\l=600m[/tex]
Hence, the first train has a length of 600 m
The train behind, or the second train, has twice the length of the first train:
[tex]l'=2l=2(600m)=1200m[/tex]
The shorter train has a length of 600m
How does friction affect velocity
Answer:
It slows it down.
Explanation:
Higher the velocity, higher the friction. Friction is the force OPPOSITE to whatever the force is going.
Question 15
Experiments performed with light indicate that light exhibits
particle properties, only
wave properties, only
both particle and wave properties
o neither particle nor wave properties
Question 16
Answer:
Both particle and wave properties
Explanation:
Light is defined as a particle and a wave, and even as a combination of a particle and a wave. A unit of light is the photon. Higher energy photons behave like particles and low energy photons behave like waves.
Experiments performed with light indicate that light exhibits both particle and wave properties.
What is the current through a 11v bulb with a power of 99w
Answer:
9.01amp
Explanation:
Power = V^2/R
Given that v = 11volts, P = 99watts
99 = 11^2/R
11×11 = 99R
121= 99R
R = 121/99
R= 1.22ohms
From ohms Law; V = IR
11volts = I × 1.22ohms
I = 11/1.23
I = 9.01 amp
Which of the following would accurately label the X axis?
Answer: Distance
I’m not sure if it is correct, but I am pretty sure it is......
I hope this helps :)
The wave formula is shown below. Check all boxes that are correct.
1) Wave speed is inversely related to the product of wavelength and frequency.
2) Wavelength has an inverse relationship with wave frequency when wave speed remains constant.
3) Wave speed is directly related to the product of wavelength and frequency.
4) Frequency has a direct relationship to wavelength when speed remains constant.
5) Wavelength and frequency are not related to wave speed.
Answer:
3) Wave speed is directly related to the product of wavelength and frequency.
4) Frequency has a direct relationship to wavelength when speed remains constant
Explanation:
V is the velocity (wave speed)
f is the frequency
the symbol next to the frequency is the wavelength
Velocity is proportional because the wavelength and frequency are multiplying.
It would be inversely proportional when the velocity is the dividend of the wavelength and frequency.
On the second statement, frequency (and wavelength) are directly related/proportional to the speed of the wave.
Force = 65 kg x 3 m/s =
What is the answer?
What units do you use for your end result?
Answer:
multiply 65kg and 3m/s^2
to get 195kgm/s
or 195N
wait is that 3m/s or 3m/s^2?
when two strands of dna line up adenine pairs up with
What adjustments to an electromagnet that causes the electromagnet to lose a strength
Explanation:
1) reduction in current
2)less no. of coils per unit length
3) removal of soft iron core
I a liter jar contains 0.5 moles of gas at a pressure of 2 ATM what is the temperature of the gas
Answer:
The temperature of the gas is 48.75 Kelvin.Explanation:
Using the ideal gas equation as shown
PV = nRT where;
P is the pressure of the gas in ATM
V is the volume of the gas
n is the number of moles
R is the ideal gas constant
T is the temperature in Kelvin
From the formula, [tex]T = \frac{PV}{nR}[/tex]
Given the following parameters V = 1litre, n = 0.5moles. pressure = 2ATM
R = 0.08206 atm L/molK
On substituting to get the temperature we have:
[tex]T = \frac{2*1}{0.08206*0.5} \\T = \frac{2}{0.04103}\\T = 48.75Kelvin[/tex]
The ratio of the potential difference across a conductor to the current in the conductor is called
A) conductivity
B) resistance
C) charge
D) power
Answer:
The ratio of the potential difference across a metallic conductor to the current in the conductor is known as.
B. Resistance.
Explanation:
According to ohms law " the current passing through a conductor is directly proportional to the potential difference between the ends provided the temperature of the wire remains constant".
What is resistance ?
Resistance is a measure of the opposition to current flow in an electrical circuit
what is a resistor ?
a resistor is a n electric conductor which forms resistance to free flow of electric current, the resistance is measured in Ω
The ratio of the potential difference across the conductor to the current is called resistance
What is Resistance?It is defined as the ratio of the potential difference across the conductor to the current. The resistance is measured in Ω.
[tex]R = \dfrac VI[/tex]
Where,
[tex]R[/tex] - resistance
[tex]V[/tex]- voltage (Potential difference)
[tex]I[/tex] - current
Therefore, the ratio of the potential difference across the conductor to the current is called resistance.
To know more about resistance.
https://brainly.com/question/4289257
What’s the resistance in the circuit
Answer:
I = 0.75 A
Explanation:
The question is not to calculate the resistance, but to calculate the current. (The resistance is already given by the value of 2 Ohm).
U = I * R
I = U / R
with U = 1.5 V and R = 2 Ohm
I = 1.5 / 2
I = 0.75 A
Which is the correct scientific notation of the number 0.000681?
Answer:
6.81 x 10^-4
Explanation:
4. In a long distance race, the athletes were expected to take four rounds of the track such that the line of finish was same as the line of start. Suppose the length of the track was 200m. What is the total distance to be covered by the athletes? What is the displacement of the athletics when they touch the finish line?
Answer:
The total distance to be covered by the athletes is 800 m
The displacement of the athletes when they touch the finish line is zero.
Explanation:
Given;
Length of the track, L = 200m
the Length of the track for a single round = 200 m
(a) Distance is a scalar quantity which has only magnitude;
If the athletes were expected to take four rounds of the track, then the total distance = 4 x 200 m = 800 m
(b) Also, if the line of finish was same as the line of start, then displacement of the athletes when they touch the finish line is zero (0 meters). This is because displacement has both magnitude and direction. Once the athlete returns to his starting point, his displacement at that point is zero.
A ladder is at rest with Oct upper end against a wall and its lower end on the ground.A worker is about to climb it.When is it more likly to slip
Answer: When the worker is on the top rung
Explanation: When the ladder was initially resting on the wall, the torque from the normal reaction on ladder from the horizontal surface is equal to the torque from the vertical surface on ladder.
The weight of the worker produces a torque which is in the direction of the torque from the normal reaction on ladder, produced by the vertical surface. Therefore for the ladder to stay in rotational equilibrium, the torque on ladder from the normal reaction produced by the horizontal surface must increase.
This increase is possible when the worker is on the lower rung, but as the worker goes high, the magnitude of normal reaction from the vertical surface would increase, thereby increasing the risk of slipping of ladder.
What is the answer to this question?
Answer:
C
Explanation:
The temperature of an object does not change when it is going through a phase change, since there is a single specific point on the temperature gradient where that change occurs. Once the phase change has occurred, the water's temperature can continue to change in that direction, but during the phase change it does not. Hope this helps!
Answer: The answer is C
Explanation:
Hope it helps :)
Which statement is NOT true about voltage?
A higher voltage means a faster current.
All electricity sources have the same voltage.
Voltage is the difference in electrical potential energy.
The unit for voltage is volt (v).
The first two choices are both false, but the second one is the falser one.
All electricity sources do not have the same voltage. The outlet in your bedroom wall supplies 120 volts, but the USB port on your laptop only supplies 5 volts, and the battery in your cellphone only supplies 3.7 volts.
All electricity sources have the same voltage isn't true
All electricity sources usually have different voltage as the number of
electrons needed to power them varies. For example heating appliances
usually have a higher amount of voltage as it requires more electrons to
increase the temperature.
The higher the amount of voltage , the higher the amount of electrons which collides more and translates to faster current which is correct.
Voltage is also known as the difference in electrical potential energy and the unit for voltage is Volt (V).
Read more on https://brainly.com/question/16589216
What is the region around a magnet where the magnetic force is exerted?
A.
magnetic poles
B.
tesla
C.
charge field
D.
magnetic field
Answer:
Magnetic field
Explanation:
Answer:
magnetic field
Explanation:
When the Net Force quadrupled from 50N to 200N, how many times bigger was the acceleration?
Answer:
acc. also gets increased four times
What is the gravitational force between Saturn and it’s moon
Answer:
The gravitational force between Saturn and it's moon is 1.62 m/s ^2
Explanation:
google it
Answer:
Explanation:
C bro
The persistence of vision for normal eye is
Answer:
The answer is 1/16
Explanation:
1. Persistence of vision refers to the optical illusion that occurs when visual perception of an object does not cease for some time after the rays of light proceeding from it have ceased to enter the eye. 2. The persistence of vision for normal eye is 1/16 if a second.
Physics question about density
So the right answer is 4kg/m^3.
Look at the attached picture
Hope it will help you
Good luck on your assignment
Answer:
The answer is option 4.
Explanation:
Firstly, you have to convert the mass of tea bagto kilogram as the question wants the unit in kg/m³.
[tex]1000g = 1kg[/tex]
[tex]100g = 1kg \div 10[/tex]
[tex]100g = 0.1kg[/tex]
So the mass of tea bag is 0.1 kg. Next you have to use density formula ρ = mass/volume. Then you have to substitute the values into the formula :
[tex]ρ = \frac{mass}{volume} [/tex]
Let mass = 0.1kg,
Let volume = 0.025m³,
[tex]ρ = \frac{0.1}{0.025} [/tex]
[tex]ρ = 4kg \: per \: {m}^{3} [/tex]
Where does the charge of a circuit go when it reaches a capacitor?
Answer:
Explanation:
When the charge of a circuit reaches the capacitor, all charge is distributed in the surface of the capacitor in order to create an electric field. The opposite of this charge is also in the capacitor, but separated.
When the capacitor receive more charges, its stability changes. Thus, the charge in one of the plates of the capacitor demands that charge on the other plate move out of the capacitor to equilibrate the charge. Thus, the current in the circuit is not interrupted.
Answer:
It gets stored somewhere in the capacitor
Explanation:
I got it right
An iron nail does not pick up paper clips as a magnet would.
Answer:
Because even if iron is magnetic its not a magnet it self unless rubbed a magnetic object
A hollow cylindrical (inner radius = 1.0 mm, outer radius = 3.0 mm) conductor carries a current of 80 A parallel to its axis. This current is uniformly distributed over a cross section of the conductor. Determine the magnitude of the magnetic field at a point that is 2.0 mm from the axis of the conductor.
Answer:
The magnetic field is [tex]B = 3 mT[/tex]
Explanation:
From the question we are told that
The inner radius is [tex]r_i = 1.00 mm =1*10^{-3} \ m[/tex]
The outer radius is [tex]r_2 = 3.00 \ mm = 3.0 *10^{-3} \ m[/tex]
The distance from the axis of the conductor is [tex]d =2.0 \ mm = 2.0 *10^{-3} \ m[/tex]
The current carried by the conductor is [tex]I = 80 A[/tex]
According to Ampere's circuital law , the magnetic field at a point that is [tex]r_3[/tex] from the axis of the conductor
[tex]B = \frac{\mu_oI}{2 \pi d } [\frac{d - r_1}{r_2 -r_1} ][/tex]
Where [tex]\mu_o[/tex] is the permeability of free space with a value of [tex]\mu_o = 4 \pi *10^{-7} N/A^2[/tex]
substituting values
[tex]B = \frac{(4 \pi *10^{-7})(80)}{2 * 3.142 * 2 *10^{=3} } [\frac{(2^2 - 1 ^2 )*10^{-3}}{(3^2 - 1^2) *10^{-3}} ][/tex]
[tex]B = 3 mT[/tex]
name and describe the process that fuels the sun
Answer:
The Sun derives all its energy from a fusion cycle. In that process, tiny hydrogen molecules combine into a continuous proton-proton chain to create larger helium nuclei. The above figure illustrates the fusion of hydrogen into helium.
Explanation:
Hope this helps.
Answer:
nuclear fusion
Explanation:
In this process, small hydrogen molecules fuse together to form bigger helium nuclei in a continuous proton-proton chain.
Which energy sources input can cause the turbine (wooden wheel)tobspin and generate electrical energy?
Answer:
The energy source which can cause the turbine (wooden wheel) to spin and generate electrical energy is hydro-energy source.
Explanation:
The energy source which can cause the turbine (wooden wheel) to spin and generate electrical energy is hydro-energy source. Hydro energy source, is the energy source gotten from the force of falling water.
Hydro energy causes the turbine to spin converting it mechanical energy and finally to electrical energy using a generator.
Force of falling water (hydro-energy source) ------>spinning of turbine (mechanical energy) ---------------> electrical energy
If a circuit has no components in it will the voltage be high or low
Answer: its low
Explanation: