Answer:
Efficiency in general means How well an object does with respect to its designated purpose for example a battery with Voltage of 10 volts won't exert 10 volts but slightly less due to internal resistance let's say 8V so efficiency will be 8/10 x100 = 80%
Same thing with a machine/engine If an engine is designed to produce 150 horsepower it won't give you the full energy due to part of the energy being dissipated in form of heat due to friction so let's say 145 hp is produced which is 96% efficiency
Given the height of rod,length of shadow of tree and length of shadow of the rod, estimate the height of the tree? Given:height of rod=150cm,Length of shadow of the rod=120cm and length of shadow of the tree =800cm
Answer:
1000 cm.
Explanation:
To obtain the estimated tree height :
(Height of rod / length of rod shadow) = (height of tree / length of tree shadow)
Substituting values into the formula :
(150cm / 120 cm) = (height of tree / 800 cm)
Using cross multiplication :
Height of tree * 120 = 150 * 800
Height of tree = (150 * 800) / 120
Height of tree = 120,000 / 120
Height of tree = 1000
Hence, estimate height of tree = 1000 cm
Explain why a person cannot dive in the Mariana Trench in the Pacific Ocean to a depth of approx. 11,000 m without appropriate protective equipment
Answer:
Plzzzz answer fast......
A rod is given a charge of +16.7 UC, how many extra protons does It contain?
Answer:
We know that the electronic charge is 1.6 E-19 coulombs
Therefore 1 coulomb of charge contains 1.6 E19 electrons
A charge of 16.7 E6 coulombs therefore contains
N = 16.7 E6 * 1.6 * E-19 = 2.67 E-12 electrons
Also, the charge on the proton equals that on the electron
Energy transfer when a moving toy car hits a tennis ball. Also, energy transfers when the tennis ball rolls and hits CDs, making the CDs fall like a domino.
Plz help me asap! I don't know the energy transfers... :(
Answer:
it would be conduction but i dont know the answer choices
Explanation:
and convection would be the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.
Why are bases of pillars of bridge
made broad?
Answer:
to lower the centre of gravity
Explanation:
You serve a volleyball with a mass of 2.5 kg. The ball leaves your hand with a speed of 23 m/s. What is the kinetic energy of the ball?
Answer:
661.25, I believe!
Explanation:
KE = (1/2)(2.5)(23)^2
KE=(1.25)(529)
KE= 661.25
A watch costs Rs. 8136 when it is 10% discounted and 13%
VAT is added then find out discount and VAT amount? By
how much percentage VAT amount is more than discount
amount.
Ans: 17%
Explanation:
lanat kabool kar
A baseball is struck home plate and acquires a speed of 60m/s. It rises to a height of 100.0 m above its starting level. Find its speed at the height
Answer:
40 m/s.
Explanation:
From the question given above, the following data were obtained:
Initial velocity (u) = 60 m/s
Height (h) = 100 m
Acceleration due to gravity (g) = 10 m/s²
Final velocity (v) =?
The velocity at height 100 m can be obtained as follow:
v² = u² – 2gh (since the ball is going against gravity)
v² = 60² – (2 × 10 × 100)
v² = 3600 – 2000
v² = 1600
Take the square root of both side
v = √1600
v = 40 m/s
Thus, velocity at height 100 m is 40 m/s
Which direction will thermal energy flow if you pick up a snowball with your bare hand? Thermal energy will flow from the snowball to your hand. Thermal energy will flow from your hand to the snowball. Thermal energy will not flow between your hand and the snowball.
Answer:
b. Thermal energy will flow from your hand to the snowball.
Explanation:
Answer:
B
Explanation:
What will happen to the size of the Aragorn Sea over time?
A 1.2 m long wave travels 11.2 m to a wall and back again in 4.0 s. What is
the FREQUENCY of the wave*
Answer:
f = 4.67 Hz
Explanation:
We can approximate the wave as a traveling wave, therefore the speed of the wave is constant
v = d / t
the total distance remember, in going to the wall and back is
d = 2 11.2 = 22.4 me
we substitute
v = 22.4 / 4.0
v = 5.6 m / s
now we can use the relationship between the speed of the wave, its wavelength and u frequency
v =λ f
f = v /λ
f = 5.6 / 1.2
f = 4.67 Hz
What is another term for a pull on an object? O A. Acceleration O B. Speed O c. Force O D. Velocity
Answer:
Acceleration
Explanation:
Two harmonic waves moving in the same direction are described by y1(x,t)=10.2sin(4x-700t) and y2(x,t)=10.2sin(4x-700t-7.9). What is the amplitude of the resultant wave at interference
Answer:
14.42 units
Explanation:
The waves are given as follows :
[tex]y_1(x,t)=10.2\sin(4x-700t)\\\\y_2(x,t)=10.2\sin(4x-700t-7.9)[/tex]
We need to find the amplitude of the resultant wave at interference. Let it be A. So,
[tex]A=\sqrt{10.2^2+10.2^2} \\\\=14.42\ units[/tex]
So, the amplitude of the resultant wave is equal to 14.42 units.
Define the types of friction and give FOUR examples of each
Static Friction
Rolling Friction
Sliding Friction
Fluid Friction
Answer:
Static Friction - acts on objects when they are resting on a surface
Sliding Friction - friction that acts on objects when they are sliding over a surface
Rolling Friction - friction that acts on objects when they are rolling over a surface
Fluid Friction - friction that acts on objects that are moving through a fluid
Explanation:
Examples of static include papers on a tabletop, towel hanging on a rack, bookmark in a book , car parked on a hill.
Example of sliding include sledding, pushing an object across a surface, rubbing one's hands together, a car sliding on ice.
Examples of rolling include truck tires, ball bearings, bike wheels, and car tires.
Examples of fluid include water pushing against a swimmer's body as they move through it , the movement of your coffee as you stir it with a spoon, sucking water through a straw, submarine moving through water.
It is a good idea to read or exchange text messages during all of the following times EXCEPT:
A.
while driving a car
B.
while eating lunch
C.
while waiting at the doctor's office
D.
while riding a bus
Please select the best answer from the choices provided.
A
B
C
D
Answer: A while driving a car. It is unsafe
Answer:
It is a good idea to read or exchange text messages during all of the following times except while driving a car.
Explanation:
Eating lunch and using your phone is very safe. The only way I can see it being bad is if you handed your phone to some toddlers and took it back without wiping it off!
If you're waiting for your appointment or waiting to reach your destination, then there is also no harm. As long as you are not driving the bus or you're not the doctor working on patients while texting, then this should be alright.
This leaves us with driving. The commercials tell us. Common knowledge tells us. Hopefully, parents or colleagues or even your own kids (I've had to do this to my dad countless times before) have told you this...
DO NOT TEXT WHILE DRIVING.
So many accidents happen solely for this reason. People, just put down the phone and wait 'til you're at a red light or, even better, when you reach your destination.
So no, it is not a good idea to read OR exchange text messages while driving. Any other time? Well, go ahead! But if you're in that driver seat and your currently in the road with other cars, take into consideration the fact you are not the only person there. Keep everyone safe and drop that phone!
....
My bad, I got long winded. Hope this helped!
Source(s): TV Commercials, myself.
Which explanation best compares the movement of particles in the three states of matter?
A.
Particles in a gas can only vibrate. In a solid, they slide against each other. In a liquid, they move freely, bouncing and bumping into each other.
B.
Particles in a solid can only vibrate. In a liquid, they slide against each other. In a gas, they move freely, bouncing and bumping into each other.
C.
Particles in a liquid can only vibrate. In a gas, they slide against each other. In a solid, they move freely, bouncing and bumping into each other.
D.
Particles in a solid can only vibrate. In a gas, they slide against each other. In a liquid, they move freely, bouncing and bumping into each other.
E.
Particles in a liquid can only vibrate. In a solid, they slide against each other. In a gas they move freely, bouncing and bumping into each other.
Answer: B
Explanation:Solids are packed thus molecules are restricted and can only vibrate. Liquids, on the other hand, molecules can move and slide against each other since they are loosely packed. Lastly, gas particles is very loosely packed so they can move freely.
A graph here shows the displacement of two walkers over time. Waliper 1 is graphed in red while walker 2 is graphed
in blue. Which statements are supported by the information in the guaph? Select ALL that apply.
)
Α)
Both walkers had the same speed overall.
B)
Walker 2 was at rest for the first five seconds.
C)
Walker 1 moved faster overall than walker 2 by the end.
D)
Walker 2 moved faster overall than walker 1 by the end.
E)
Both walkers had reached the same distance at fifteen seconds.
Answer:
B) Walker 2 was at rest for the first five seconds. D) Walker 2 moved faster overall than walker 1 by the end. E) Both walkers had reached the same distance at fifteen seconds.
Explanation:
I did the UsaTestPrep
16. A strong acid has a pH close to 7
A.True
B.False
Answer:
I think it's true.
Hope this helps .
Explanation:
The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic.
Which of the following best describes why tidal energy is considered a renewable energy resource? A. The Moon receives energy from the Sun, which is a renewable resource. B. Humans can create more tidal energy by setting up more tidal energy plants. C. Ocean water will never be exhausted. D. Tidal energy is replaced naturally by the Moon's gravity.
Answer:
D. Tidal energy is replaced naturally by the Moon's gravity.
Explanation:
The reason tidal energy is considered a renewable energy resource is that Tidal energy is replaced naturally by the Moon's gravity. The Moon's gravity creates bulges on the side of Earth that is closest and farthest from the Moon. These bulges also pull water causing high tides in those areas. As the Earth rotates these areas experience low tide while the areas that had low tide now experience high tide. This constant shift creates tidal energy every day, which is replenished naturally.
2. The force between charges is 7 N. The distance between the charges is 4 x 10-6 m. If one of the charges is 2 x 10-8 C, what is the strength of the other charge?
3. A pair of equal charges are separated by .75 m. There's a 2500 N force acting on them. What is the strength of the charge?
Plz help!!!!!!
Answer:
2) 6.22 × 10^-13
3) 4.56 × 10^-4
Explanation:
Which is an example of a polyatomic ion?
Answer:
Well-known examples of such polyatomic ions are the sulfate ion (SO42–), the hydroxide ion (OH–), the hydronium ion (H3O+), and the ammonium ion (NH4+).
Explanation:
Answer:
is there more context to go with this question? Like a photo?
I will give it my best shot anyhoo
Explanation:
Polyatomic ions: they are covalently bonded groups of atoms and having a positive or negative charge caused by the formation of an ionic bond with another ion.
And if your question is anything like the one I had a few days ago on a test, your answer would be something like "Both hydroxide cation (OH -) and phostphate cation (PO 4 3 -) are polyatomic ions)
An electron (e = 1.6 x 10-19 C) is traveling at 4.00 x 107 m/s due North in a horizontal plane through a point where the earth’s magnetic field has a component to the North of 2.00 x 10-5 T and a downward (in to the earth) of 5.00 x 10-5 T. Calculate the magnetic force (magnitude and direction) on the electron and its acceleration. Me = 9.11 x 10-31 kg
Answer:
Explanation:
Force on the electron due to magnetic field 's north component will be zero because both velocity of electron and direction of magnetic field are same .
Force due to downward component of magnetic field
= B q v where B is magnetic field , q is charge moving and v is velocity of charge
F = 5 .00 x 10⁻⁵ x 1.6 x 10⁻¹⁹ x 4 x 10⁷
= 32 x 10⁻¹⁷ N
acceleration = F / m where m is mass of electron
= 32 x 10⁻¹⁷ / 9.11 x 10⁻³¹
= 3.5 x 10¹⁴ m/s²
list down the different phases of the Moon
Answer:
new Moon.
waxing crescent Moon.
first quarter Moon.
waxing gibbous Moon.
full Moon.
waning gibbous Moon.
last quarter Moon.
waning crescent Moon.
Explanation:
Answer:
NEW MOON
WAXING CRESCENT
FIRST QUARTER
WAXING GIBBOUS
FULL MOON
THIRD QUARTER
WANING GIBBOUS
WANING CRESCENT
Explanation:
HOPE IT HELPS
A rock with a mass of 6 grams has greater thermal energy than a rock with a mass of 7 grams. True or false?
Answer:
Explanation:
False
Using Ohms Law, calculate the current that would exist in a circuit having a voltage of 240V experiencing 110 Ohms of resistance
To find the Voltage, ( V ) [ V = I x R ] V (volts) = I (amps) x R (Ω)
To find the Current, ( I ) [ I = V ÷ R ] I (amps) = V (volts) ÷ R (Ω)
To find the Resistance, ( R ) [ R = V ÷ I ] R (Ω) = V (volts) ÷ I (amps)
To find the Power (P) [ P = V x I ] P (watts) = V (volts) x I (amps)
A baseball sits motionless near first base on a baseball diamond. What statement best explains why the baseball remains motionless?
Answer:
Because no one is using that ball, so it is motionless
Answer:
No one is using the ball (dead ball) and therefore it is motionless and out of play
Explanation:
The object having uniform velocity has zero acceleration, why?
How can a conductor be made superconductor?
Answer:
a superconductor in a magnetic field and you'll make electric currents flow through its surface. These currents create a magnetic field that exactly cancels the original field trying to get inside the superconductor and repelling the magnetic field outside.
Explanation:
Help!!! Please need it fast. If correct I’ll give b
Answer:
if bother parents have brown eyes but they carry the allele for blue eyes a quarter of the kids will have blue eyes and three quarters will have brown eyes. hope this help I'm sorry if it doesn't.
What current flows through a 15 ohm fixed resistor when it operates on a 120-volt outlet?
Answer: current is 8.0 A
Explanation: R= U/I I = U/R = 120 V/15 Ω= 8.0 A