Answer:
0.50 A
Explanation:
We can find the current from this through Ohm's Law:
V = IR
Now, in it's original form, we're only looking for Voltage. However, we can switch this formula around to find each part of it:
I = V / R (current)
R = V / I (resistance)
In this case, we'll use the formula for current:
V = 120 V
R = 240 Ω
I = ?
I = 120 / 240
I = 0.5 A
Two students are balancing on a 10m seesaw. The seesaw is designed so that each side of the seesaw is 5m long. The student on the left weighs 60kg and is sitting three meters away from the fulcrum at the center. The student on the right weighs 45kg. The seesaw is parallel to the ground. The mass of the board is evenly distributed so that its center of mass is over the fulcrum. What distance from the center should the student on the right be if they want the seesaw to stay parallel to the ground?
a. 4m
b. 5m
c. 2m
d. 3m
NO LINKS.
Answer:
x = 4 m
Explanation:
For this exercise we must use the rotational equilibrium relationship, where we place zero at the turning point and counterclockwise rotations we will consider positive
as it indicates that the bar is in equilibrium, its center of mass coincides with the turning point, so the distance is zero and does not create torque on the system
∑τ = 0
W 3 - w x = 0
x = 3W / w
x = 3 Mg / mg
x = 3 M / m
let's calculate
x = 3 60/45
x = 4 m
The total resistance of a series circuit is 15.0 ohms what is the second resistance of the first resistance is 10.0 ohms?
A. less than 5.0 ohms
B. 5.0 ohms
C. 15 ohms
D. 25 ohms
What is the net force on a skydiver falling with a constant velocity of 0 m/s downward?
Which is one way to determine whether a reaction was a chemical reaction or a nuclear reaction?
Answer:
Check how much energy was released during the reaction or check for a change in total mass
write the dimensional formula of gravitational constant and specific heat capacity.
Answer:
SEE EXPLANATION
Explanation:
The dimensional formula of gravitational constant is given by,
M^-1 L^3 T^-2
Where,
M = Mass
L = Length
T = Time
Dimensional formula of Specific Heat Capacity =[ M^0L^2T^-2K^-1]
How does a generator use the effect you noticed in the pickup coil to generate electrical energy? What energy transformations are taking place? Why does a generator make alternating current? What change would have to be made to make direct current?
Answer:
Movement of Electrons in opposite direction of the rotation of the pickup coil leads to the direction of Electrical energy ( Alternating current ).
Explanation:
For a Generator to generate electricity, Electrons that is found in the rotating coil of the Generator will experience some sort of force that makes them to start moving in a direction that is perpendicular to the direction of the rotating/pickup coil found in the Generator.
The conversion of mechanical energy (Rotation of the pickup coil ) to electrical energy takes place in the Generator
The generator makes an alternating current because electrons move in opposite direction of the rotating coil
In other to generate a Direct current using a generator we have to replace the slip rings with commutator.
A 2.4 tonne boulder falls from the top of a 125 m cliff onto the ground below
What speed does it hit the ground with?
(Ignore air resistance.)
Give your answer to the nearest 0.1 m/s
Use g = 9.8 m/s2 for the acceleration due to gravity.
Answer:
49.5 m/s
Explanation:
Let's use the energy approach to solve this problem.
We are given the mass and displacement of the boulder.
The formula for potential energy is PE = mgh.
The formula for kinetic energy is KE = 1/2mv².
If we ignore air resistance, we can use the conservation of energy to solve this problem by setting PE and KE equal to each other. By doing so, we realize that the mass of the boulder does not affect the speed that it hits the ground (final velocity).
mgh = 1/2mv²Divide both sides of the equation by m.
gh = 1/2v²Let's take the downwards direction as positive. The displacement of the boulder is 125 m and g = 9.8 m/s².
(9.8)(125) = 1/2v²Now we can solve for v.
1225 = 1/2v²Multiply both sides by 2.
2450 = v²Take the square root of both sides.
v = 49.49747468Rounded to the nearest 0.1 m/s, the final velocity of the boulder is 49.5 m/s.
When two objects are at the same temperature we say they are at
Answer:
equal temperatures
Explanation:
what is the comparison of Wind turbine and other energy sources?
AnWind power or wind energy is the use of wind to provide mechanical power through wind turbines to turn electric generators for electrical power. Wind power is a popular sustainable, renewable source of power that has a much smaller impact on the environment compared to burning fossil fuels. Wind farms consist of many individual wind turbines, which are connected to the electric power transmission network. Onshore wind is an inexpensive source of electric power, competitive with or in many places cheaper than coal or gas plants. Onshore wind farms have a greater visual impact on the landscape than other power stations, as they need to be spread over more land and need to be built away from dense population. Offshore wind is steadier and stronger than on land and offshore farms have less visual impact, but construction and maintenance costs are significantly higher. Small onshore wind farms can feed some energy into the grid or provide power to isolated off-grid locations. The wind is an intermittent energy source, which cannot be dispatched on demand. Locally, it gives variable power, which is consistent from year to year but varies greatly over shorter time scales. Therefore, it must be used together with other power sources to give a reliable supply. Power-management techniques such as having dispatchable power sources (often gas-fired power plant or hydroelectric power), excess capacity, geographically distributed turbines, exporting and importing power to neighboring areas, grid storage, reducing demand when wind production is low, and curtailing occasional excess wind power, are used to overcome these problems. As the proportion of wind power in a region increases the grid may need to be upgraded. Weather forecasting permits the electric-power network to be readied for the predictable variations in production that occur. In 2019, wind supplied 1430 TWh of electricity, which was 5.3% of worldwide electrical generation, with the global installed wind power capacity reaching more than 651 G…swer:
Explanation:
The Nardo ring is a circular test track for cars. It has a circumference of 12.5 km. Cars travel around the track at a constant speed of 100 km/h. A car starts at the easternmost point of the ring and drives for 30 minutes at this speed.
Required:
a. What distance, in km, does the car travel?
b. What is the magnitude of the car's displacement, in km, from its initial position?
c. What is the speed of the car in m/s?
Answer: 50 km, 0, 27.78 m/s
Explanation:
Given
Circumference of the track is [tex]12.5\ km[/tex]
Speed of car is [tex]100\ km/h[/tex]
Car drives for [tex]30\ \text{minute}\ or\ 0.5\ hr[/tex]
(a)Distance traveled is
[tex]\Rightarrow D=100\times 0.5\\\Rightarrow D=50\ km[/tex]
(b)displacement of the car
It can be observed that 12.5 is a multiple of 50, that is, 50 km can be interpreted as 4 complete rounds of the track.
Therefore, the displacement of the car is zero.
(c)To convert kmph to m/s, multiply the entity by [tex]\frac{5}{18}[/tex]
[tex]\Rightarrow 100\times \dfrac{5}{18}\\\\\Rightarrow 27.78\ m/s[/tex]
which one hurry i need help pls dont get me wrong ..
Answer:
OPEN
Explanation:
An intentionally open circuit would be the circuit to the lights in the room that are turned off. There is no closed path available for the electricity to flow to the lights because the switch is in the "off" position which "opens" the path the electricity would normally flow through.
As a galaxy evolves and becomes more massive, what is most likely to happen?
Answer:
Explanation:
The most likely thing that would happen is that the galaxies continue becoming more and more massive, eventually becoming part of a galaxy cluster. These are massive but cluttered parts of the universe that hold many galaxies extremely close to one another. This also leads to galaxies colliding with one another, although when this happens they usually seem to pass right through each other as if they were ghosts. This is simply due to their sheer size and distance between their bodies of mass.
Answer:
It will merge with other galaxies
Explanation:
Pearson Connexus 2023
4. How do ordinary objects behave in microgravity?
Bubbles rose faster
Bubbles paused
Bubbles kept rising
Answer:
Bubbles paused
Explanation:
the air bubble doesn't rise because it is no lighter than the water around it—there's no buoyancy. The droplet doesn't fall from the leaf because there's no force to pull it off. It's stuck there by molecular adhesion.
for instance, onto the International Space Station, gravity becomes negligible, and the laws of physics act differently than here on Earth
On Earth, the buoyancy of the air bubbles causes them to rise to the top together, creating a segregation between air and water. However, in microgravity, nothing forces the air bubbles to interact and thus rise together, Green said.
At what rate is thermal energy being generated in the 2R-resistor when ε = 12 V and R = 3.0 Ω?
Answer:
6 W
Explanation:
From the given information:
The resistance in Parallel for 2R is:
[tex]R_p = \dfrac{2R\times 2R}{2R+2R} \\ \\ R_p= R[/tex]
The equivalent resistance:
[tex]R_{eq} = R_p + R = 2R[/tex]
[tex]R_{eq} = 2(3)[/tex]
[tex]R_{eq} = 6 \ \ ohms[/tex]
The current through the circuit in R is:
[tex]= \dfrac{12}{R+R} \\ \\ = \dfrac{12}{2\times 3} \\ \\ = 2 A[/tex]
The current through the circuit in 2R is:
[tex]I_2R = (2A) \times \dfrac{2R}{2R+2R}[/tex]
[tex]I_2R = 2A \times \dfrac{1}{2} \\ \\ I_2R = 1A[/tex]
Finally, the thermal energy:
[tex]P_{2R} = (1)^2 (2R)[/tex]
[tex]P_{2R} = (1)^2 (2\times 3)[/tex]
[tex]P_{2R} = 6W[/tex]
A loudspeaker, mounted on a tall pole, is engineered to emit 75% of its sound energy into the forward hemisphere, 25% toward the back. You measure an 85 dB sound intensity level when standing 3.5 m in front of and 2.5 m below the speaker. What is the speaker’s power output?
Answer:
"0.049 W" is the correct answer.
Explanation:
According to the given question,
[tex]r = \sqrt{(3.5)^2+(2.5)^2}[/tex]
[tex]=\sqrt{8.5}[/tex]
[tex]SL=85[/tex]
As we know,
⇒ [tex]SL=10 \ log(\frac{I}{I_o} )[/tex]
[tex]85=10 \ log(\frac{I}{10^{-12}} )[/tex]
[tex]I=3.162\times 1^{-4} \ W/m^2[/tex]
Now,
⇒ [tex]P_{front} = I(2\pi r^2)[/tex]
[tex]=(3.162\times 10^{-4})(2\pi\times 18.5)[/tex]
[tex]=0.0368 \ W[/tex]
[tex]=0.75 \ P[/tex]
or,
[tex]=0.049 \ W[/tex]
You are designing an airplane propeller that is to turn at 2400 rpm (Fig. 9.13a). The forward airspeed of the plane is to be 75.0 m/s 75.0 m/s, and the speed of the propeller tips through the air must not exceed 270 m/s 270 m/s. (This is about 80% of the speed of sound in air. If the propeller tips moved faster, they would produce a lot of noise.) What is the maximum possible propeller radius?
Answer:
r = 1.07 m
Explanation:
The maximum radius of the propeller that can be allowed is given by the following formula:
[tex]v = r\omega\\\\r = \frac{v}{\omega}[/tex]
where,
r = maximum possible radius of the propeller = ?
v = maximum possible linear speed of the propeller = 270 m/s
ω = angular speed of the propeller = (2400 rpm)(2π rad/1 rev)(1 min/60 s)
ω = 251.33 rad/s
Therefore,
[tex]r = \frac{270\ m/s}{251.33\ rad/s}[/tex]
r = 1.07 m
An idea to explore the nearest Earth-sized planet in a habitable zone to our Sun is to attach a small sensor array to a 4 m by 4 m solar sail and shine a 100 GW laser on the solar sail for 10 minutes. This will get the spaceship up to speed after which it will coast the rest of the way at the speed attained after the 10 minutes of acceleration. Assume the sensor array and solar sail has a mass of 3 grams. The nearest Earth-sized planet in a habitable zone orbits the Alpha Centauri system at 4.3 Lightyears. 1 GW = 1*109 W. 1 Light year = 4*1016 m. Assume a perfectly reflecting solar sail and assume all 100 GW of power are intercepted by the solar sail.
a. What is the pressure on the Solar Sail from the laser?
b. What is the force on the Solar Sail from the laser?
c. What speed will the spaceship attain after 10 minutes assuming it started from rest and assuming a constant acceleration?
d. How long will it take the spaceship to reach Alpha Centauri in years?
Solution :
Given data:
Area of the solar sail, A = 16 [tex]$m^2$[/tex]
Mass (array + sail), m = [tex]$3 \times 10^{-3}$[/tex] kg
Power, P = 100 GW
= [tex]$10^{11}$[/tex] W
Time, t = 10 min
= 10 x 60 s
Distance, D = [tex]$4.3 \times 4 \times 10^{16}$[/tex] m
Kinetic energy, [tex]$KE=\frac{1}{2}mv^2=P\times t$[/tex]
[tex]$v=\sqrt{\frac{2Pt}{m}}$[/tex]
[tex]$v=\sqrt{\frac{2\times 10^{11}\times 600}{3 \times 10^{-3}}}$[/tex]
[tex]$=2 \times 10^8$[/tex] m/s
So, the acceleration is [tex]$a=\frac{v}{t}$[/tex]
[tex]$a=\frac{2 \times 10^8}{6 \times 10^2} \ m/s^2$[/tex]
[tex]$=333333.33 \ m/s^2$[/tex]
Therefore, force,
[tex]$F = ma$[/tex]
[tex]$=3 \times 10^{-3}\times 333333.33$[/tex]
= 1000 N
Pressure, [tex]$P=\frac{F}{A}$[/tex]
[tex]$=\frac{1000}{16}$[/tex]
[tex]$=62.5 \ N/m^2$[/tex]
Therefore, time taken is t
Now the distance is
[tex]$d_1=\frac{1}{2}at_1^2$[/tex]
[tex]$d_1=0.5 \times 333333.33 \times (600)^2$[/tex]
[tex]$=6 \times 10^{10} \ m$[/tex]
Now, the distance, [tex]$d_2 = D-d_1=v.t_2$[/tex]
Now, [tex]$t_2=\frac{(17.2 \times 10^{16})-(6 \times 10^{10})}{2 \times 10^8}$[/tex]
= 859999700 s
Therefore, total time is
[tex]$T=t_1+t_2$[/tex]
= 86000300 s
= 27.27 years
So this helicopter pilot dropped me in the middle of an absolutely smooth frictionless
lake. He thought it was really funny. The only thing the pilot let me take is a bowling
ball. I tried to claw my way to the shore but was unable to get any horizontal force on
the super slippery zero friction ice. Explain how I can get to shore and why it will
work before I freeze to death. This test is about momentum. I wonder if my solution
has anything to do with that ...
The FitnessGram™ Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. [beep] A single lap should be completed each time you hear this sound. [ding] Remember to run in a straight line, and run as long as possible. The second time you fail to complete a lap before the sound, your test is over. The test will begin on the word start. On your mark, get ready, start.
What is the definition of Heat Transfer
Answer:
Heat transfer is an engineering discipline that concerns the generation, use, conversion, and exchange of heat (thermal energy) between physical systems.
Explanation:
Answer:
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and transfer of energy by phase changes.
Explanation:
hope that helps
in a simple machine the input work is 187.5 N and output work is 125N. If load distance is 25 cm and effort distance is 75 cm calculate value of load and effort
Answer:
1. Laod = 500 N
2. Effort = 250 N
Explanation:
From the question given above, the following data were obtained:
Input work = 187.5 J
Output work = 125 J
Load distance = 25 cm
Effort distance = 75 cm
1. Determination of the load.
Output work = 125 J
Load distance = 25 cm = 25/100 = 0.25 m
Load =?
Output work = Load × Load distance
125 = Load × 0.25
Divide both side by 0.25
Load = 125 / 0.25
Laod = 500 N
2. Determination of the effort.
Input work = 187.5 J
Effort distance = 75 cm = 75/100 = 0.75 m
Effort =?
Input work = Effort × Effort distance
187.5 = Effort × 0.75
Divide both side by 0.75
Effort = 187.5 / 0.75
Effort = 250 N
Divergent boundaries that involve the crust that is spreading apart are
found ... *
135g of an unknown substance gains 9133 J of heat as it is heated from 25⁰C to 100⁰C. Using the chart below, determine the identity of the unknown substance.
Answer:
The unknown substance is Aluminum.
Explanation:
We'll begin by calculating the change in the temperature of substance. This can be obtained as follow:
Initial temperature (T₁) = 25 ⁰C
Final temperature (T₂) = 100 ⁰C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 100 – 25
ΔT = 75 ⁰C
Finally, we shall determine the specific heat capacity of the substance. This can be obtained as follow:
Change in temperature (ΔT) = 75 ⁰C
Mass of the substance (M) = 135 g
Heat (Q) gained = 9133 J
Specific heat capacity (C) of substance =?
Q = MCΔT
9133 = 135 × C × 75
9133 = 10125 × C
Divide both side by 10125
C = 9133 / 10125
C = 0.902 J/gºC
Thus, the specific heat capacity of substance is 0.902 J/gºC
Comparing the specific heat capacity (i.e 0.902 J/gºC) of substance to those given in the table above, we can see clearly that the unknown substance is aluminum.
On a day when the water is flowing relatively gently, water in the Niagara River is moving horizontally at 4.5 m/s before shooting over Niagara Falls. After moving over the edge, the water drops 53 m to the water below. If we ignore air resistance, how much time does it take for the water to go from the top of the falls to the bottom? How far does the water move horizontally during this time?
Answer: 3.28 s, 14.76 m
Explanation:
Given
Water moves horizontally with a speed of [tex]v=4.5\ m/s[/tex]
It falls from a height of [tex]h=53\ m[/tex]
Time is taken to fall this much height is
[tex]\Rightarrow t=\sqrt{\dfrac{2h}{g}}\quad [\text{As there is no initial vertical velocity}]\\\\\Rightarrow t=\sqrt{\dfrac{2\times 53}{9.8}}\\\\\Rightarrow t=3.28\ s[/tex]
In this time, water moves horizontally by
[tex]\Rightarrow d=4.5\times 3.28\\\Rightarrow d=14.76\ m[/tex]
Does a ball rolling on an inclined plane have the same acceleration on the way up as it does on the way down?
Answer:
No, it does not.
Explanation:
According to the Law of Gravitation, something going down has more kinetic energy than something going up because it attracts pressure from around it when going down. When it goes up, it has less gravitational force and inertia also stops the ball from rolling upward. Therefore, without the amount of kinetic energy, it will not have the same amount of acceleration.
HURRY ILL GIVE 15 POINTS
Carla draws two circuit diagrams that connect the same components in different ways as shown which statement about the circuit is correct?
Circuit A is correct
Magnets on the tracks
How can levitating trains support the claim that magnetic fields exist between objects exerting magnetic force on each other even when there is no physical contact?
Answer:
Explanation: They levitate sort of because when to opposite forces of magnets cant go together they repelAlthough we have discussed single-slit diffraction only for a slit, a similar result holds when light bends around a straight, thin object, such as a strand of hair. In that case, a is the width of the strand. From actual laboratory measurements on a human hair, it was found that when a beam of light of wavelength 631.8 nm was shone on a single strand of hair, and the diffracted light was viewed on a screen 1.20 m away, the first dark fringes on either side of the central bright spot were 5.02 cm apart.
Required:
How thick was this strand of hair?
Answer:
d = 1.51 x 10⁻⁵ m = 15.1 μm
Explanation:
We will use young's Double Slit formula here:
[tex]Y = \frac{\lambda L}{d}\\\\d = \frac{\lambda L}{Y}[/tex]
where,
d = width of strand = ?
λ = wavelength = 631.8 nm = 6.318 x 10⁻⁷ m
L = Screen to hair distance = 1.2 m
Y = fringe spacing = 5.02 cm = 0.0502 m
Therefore,
[tex]d = \frac{(6.318\ x\ 10^{-7}\ m)(1.2\ m)}{0.0502\ m}[/tex]
d = 1.51 x 10⁻⁵ m = 15.1 μm
Find speed if distance is 6 m
and time is 5.2 sec.
Answer:
Distance = 6 m
Time = 5.2 sec
speed = x
formula to find speed is distance upon time
Now,
speed = 6/5.2
speed = 1.15
Consider a father pushing a child on a playground merry-go-round. The system has a moment of inertia of 84.4 kg.m^2. The father exerts a force on the merry-go-round perpendicular to its radius to achieve an angular acceleration of 4.44 rad/s^2.
Required:
a. How long (in s) does it take the father to give the merry-go-round an angular velocity of 1.53 rad/s? (Assume the merry-go-round is initially at rest.)
b. How many revolutions must he go through to generate this velocity?
c. If he exerts a slowing force of 270 N at a radius of 1.20 m, how long (in s) would it take him to stop them?
Answer:
Explanation:
Given that:
the initial angular velocity [tex]\omega_o = 0[/tex]
angular acceleration [tex]\alpha[/tex] = 4.44 rad/s²
Using the formula:
[tex]\omega = \omega_o+ \alpha t[/tex]
Making t the subject of the formula:
[tex]t= \dfrac{\omega- \omega_o}{ \alpha }[/tex]
where;
[tex]\omega = 1.53 \ rad/s^2[/tex]
∴
[tex]t= \dfrac{1.53-0}{4.44 }[/tex]
t = 0.345 s
b)
Using the formula:
[tex]\omega ^2 = \omega _o^2 + 2 \alpha \theta[/tex]
here;
[tex]\theta[/tex] = angular displacement
∴
[tex]\theta = \dfrac{\omega^2 - \omega_o^2}{2 \alpha }[/tex]
[tex]\theta = \dfrac{(1.53)^2 -0^2}{2 (4.44) }[/tex]
[tex]\theta =0.264 \ rad[/tex]
Recall that:
2π rad = 1 revolution
Then;
0.264 rad = (x) revolution
[tex]x = \dfrac{0.264 \times 1}{2 \pi}[/tex]
x = 0.042 revolutions
c)
Here; force = 270 N
radius = 1.20 m
The torque = F * r
[tex]\tau = 270 \times 1.20 \\ \\ \tau = 324 \ Nm[/tex]
However;
From the moment of inertia;
[tex]Torque( \tau) = I \alpha \\ \\ Since( I \alpha) = 324 \ Nm. \\ \\ Then; \\ \\ \alpha= \dfrac{324}{I}[/tex]
given that;
I = 84.4 kg.m²
[tex]\alpha= \dfrac{324}{84.4} \\ \\ \alpha=3.84 \ rad/s^2[/tex]
For re-tardation; [tex]\alpha=-3.84 \ rad/s^2[/tex]
Using the equation
[tex]t= \dfrac{\omega- \omega_o}{ \alpha }[/tex]
[tex]t= \dfrac{0-1.53}{ -3.84 }[/tex]
[tex]t= \dfrac{1.53}{ 3.84 }[/tex]
t = 0.398s
The required time it takes= 0.398s
A truck was carrying a substance in a tank. The molecules of that substance were moving away from each other. The truck parked overnight in a place where energy transferred out of the substance. In the morning, the substance was a gas. How were the molecules moving in the morning? Explain why the molecules were moving that way after energy was transferred out of them.
(Make it ask long as you need)
Or (short)
Answer:
In the morning the molecules were moving away from each other with a smaller speed than when the truck was carrying the substance.
Explanation: