Answer:
Energy cannot be created or destroyed.
Explanation:
its in the name, law of "conservation" of energy. energy can only change forms not be destroyed
Answer: Energy cannot be created or destroyed.
Explanation: The law of conservation of energy states that energy can neither be created nor be destroyed due to energy loss. It can only change its states from one energy state to another.
The efficiency is defined as the ratio of output work to the input work. The efficiency of the fan is not 100%. Because some of the energy is lost in the form of heat and sound. No machine is 100% efficient. There is always some loss of energy takes place.
I really hope this helps and sorry it's late.
I NEED THIS ANSWERED ASAP WITH THE RIGHT ANSWER
A bicycle with a 15 kg mass is easily stopped when a force of 60 N is applied. How much force would be needed to stop the bicycle if the time allowed to stop the bike was doubled?
Answer:
Going downhill at a steady speed, the forces along the direction of motion are:
net force = m * a = 0
W * sin(7) - Fdrag = 0
so Fdrag = m * g * sin(7) where m=62.kg and g=9.8m/sec^2
Explanation:
Two rocks of masses 5 kg and 10 kg a dropped from rest from a height of 20 m above ground. Ignore all friction and air resistance. Just before
they hit the ground, which statement is true about the rocks?
(A) The value for the acceleration of the 5 kg rock is the same as the value for the 10 kg rock, but their velocity values are different.
(B) The values for the acceleration and velocity of the 5 kg rock are greater than the values for the 10 kg rock.
(C) The values for the acceleration and velocity of the 5 kg rock are less than the values for the 10 kg rock.
(D) The values for the acceleration and velocity of the 5 kg rock are the same as the values for the 10 kg rock.
Answer:
D
Explanation:
F=ma
F of 5 kg rock = 49N
F of 10 kg rock = 98 N
Divide by respective masses to get acceleration, and of course you will get 9.8 m/s^2 for both.
Now, use potential energy equals kinetic energy. mgh=(1/2)mv^2 mass cancels out of the equation, since it's on both sides, so we can stop right there. We have algebraically determined that mass does not affect acceleration or velocity!
Hope this helped.
Warm air rises because it has less ___________.
Answer:
because it is less dense than the surrounding air
Explanation:
c. Before space travel some people thought rockets would not work in space because there was no
atmosphere for the rocket exhaust to push against. Explain the error in this thinking using Newton's
third law.
3.1. A stone of mass 2kg is thrown vertically upward with a speed
of 20m's Calculate the maximum height reached.
Answer:
20.41 m
Explanation:
Let's list out the relevant variables in this problem. Take the upwards direction to be positive and the downwards to be negative.
v₀ = 20 m/sv = 0 m/sa = -9.8 m/s² Δy = ?We are using the fact that at maximum height, the object's velocity is 0 m/s right before it changes direction to fall vertically back down to Earth.
Find the constant acceleration equation that contains these four variables.
v² = v₀² + 2aΔySubstitute the known values into the equation and solve for Δy, the maximum height.
(0)² = (20)² + 2(-9.8)Δy 0 = 400 - 19.6Δy -400 = -19.6Δy Δy = 20.4081632653The maximum height of the stone is 20.41 m. Notice that its mass was irrelevant when solving for its maximum height when thrown.
Shrill sound is of -------------- *
Higher frequency
Lower frequency
Higher amplitude
Lower amplitude
Answer:
Higher frequency.
Explanation:
Sound are mechanical waves that are highly dependent on matter for their propagation and transmission.
Sound travels faster through solids than it does through either liquids or gases. A student could verify this statement by measuring the time required for sound to travel a set distance through a solid, a liquid, and a gas.
Mathematically, the speed of a sound is given by the formula:
[tex] Speed = wavelength * frequency [/tex]
Generally, the frequency of a sound wave determines the pitch of the sound that would be heard.
A shrill sound refers to a type of sound that is typically sharp, high pitched and as such has higher frequency.
Hence, shrill sound is of higher frequency.
In a penalty kick, a soccer player kicks the ball from ground level with an initial velocity of .5.0 m/s,20.0^ above the horizontal . Assume that air resistance is negligible . What is the maximum height , y max of the soccer ball ?
A)0.51
B)3.2
C)3.7
D)8.6
What is the flight time of the soccer ball in the previous problem?
A)0.76 s
B)0.87 s
C) 1.3 s
D) 1.7 s
Solids, liquids, and gases are very often depicted as groups of particles inside containers of fixed shape and dimension.
Using the simple model of solid, liquid, and gas, which of the following descriptions of physical properties is CORRECT?
A
The physical properties of this phase of matter are that the particles take the shape of the container, do not fill the entire volume, and are very strongly attracted to each other.
B
The physical properties of this phase of matter are that the particles take the shape of the container, do not fill the entire volume, and are strongly attracted to each other.
C
The physical properties of this phase of matter are that the particles take the shape of the container, they fill the entire volume of the container, and are strongly attracted to each other.
D
The physical properties of this phase of matter are that the particles do not take the shape of the container, they fill the entire volume, and are weakly attracted to each other.
Answer:
The answer would be B
Explanation:
Hope you have a good day
Which is NOT an example of evidence that shows a chemical reaction occurred?
change in color
change in temperature
change in shape
bubbles, fizzing
Provide two examples of how health care workers can demonstrate their commitment to quality control through their personal appearance.
Carbon (C) is an element found in living organisms. How would carbon be classified in the hierarchy of organisms?
Answer:
Explanation:
A cell
A 5 kg object is moving downward at a velocity of 12 m/s and is
currently 2.6 meters above the ground.
calculate its kinetic energy
calculate its potential energy
calculate its mechanical energy
Answer:
the first one i think
Explanation:
What is the speed of a rocket that travels 10000 meters in 15 seconds?
Help a brother out
Answer:
666.67
Explanation:
the formula is speed = distance ÷ time
by the way I approximated the answer hope that it help I'm not sure it's right but I hope it is.
A piece of metal has a volume of 2.0 x 10-5 m3.
The density of the metal is 8.0 x 103 kg/m3.
What is its mass?
A. 2.5 103 kg
B.4.0 x 102 kg
C.1.6 101 kg
D.1.6 x 105 kg
a car is traveling north on the interstate. They cover 645 miles in 9 hours. What is the car's average velocity ?
Answer:
71.6 mph
Explanation:
you would do 645 divided by 9 which would give you 71.6
Classify each substance as either a conductor or insulator.
A sample of mercury:
✔ conductor
A piece of glass:
✔ insulator
A rubber hose:
✔ insulator
A negatively ionized lithium paste:
✔ conductor
The correct classification of each substance is as follows:
A sample of mercury: conductorA piece of glass: insulatorA rubber hose: insulatorA negatively ionized lithium paste: conductorWhat are conductors and insulators?A conductor is a substance that can transmit electricity, heat, light or sound while an insulator is a substance that does not transmit heat, sound or electricity.
Conductors are usually metals while insulators are usually non-metals. Examples of conductors include;
IronAluminumCopperExamples of insulators include;
GlassPaperWoodSilkTherefore, the correct classification of each substance is as follows:
A sample of mercury: conductorA piece of glass: insulatorA rubber hose: insulatorA negatively ionized lithium paste: conductorLearn more about conduction at: https://brainly.com/question/18084972
#SPJ1
Answer:
Explanation:
E2020
Which law best describes this behavior of gases in the Sun?
Answer:
The extreme pressure from the weight of the gases that make up the Sun raises the temperature of the core enough for the nuclear reactions to take place, Which law best describes this behavior of gases in the Sun? A. Charles law.
Explanation:
if it is helpful....... plzz like and follow
What is the cheetahs momentum?
Answer:
Momentum is mass*velocity. Cheetah: 74*31 = 2294 kg-m/s.
6. What is the resultant force on each car below? Remember TWO pieces of
information are needed.
7. What additional statement could we make about each car? Think about what key
words we could use
Explanation:
In first case, the forces on LHS and on RHS is the same i.e. 3 N. The force acting on the car is balanced force. As a result, the car will not move at all.
In second case,
Force on RHS = 2000 N
Force on LHS = -6000 N
Net force acting on it is given by :
F = 2000+(-6000)
= -4000 N
Hence, this is the required solution.
testing related to criteria
Answer: Test criteria offers assistance the analyzer(s) to compose the test prepare. They ought to be chosen in understanding with the accessible test exertion. Test scope measures are characterized as a proportion between the test cases required for fulfilling the criteria and those of these which have been executed
Answer 7575
Explanation: the numbers are cool
What is the object’s average acceleration between 0.0 s and 5.0 s?
ANSWER FAST! PLEASEE
Answer:
[tex]2.5[/tex]
Explanation:
[tex]0.0+5.0=5.0[/tex]
[tex]\frac{5}{2} =2.5[/tex]
hope this helps!!!!!!!!!!
From an apple tree 2 metres high, a 100g mass apple fell of the tree, what work did it do?
Answer:
W = 1.96 J
Explanation:
Given that,
The mass of an Apple, m = 100 g = 0.1 kg
It fell from 2 metres high tree.
We need to find the work done by it. The work done is given by :
[tex]W=mgh\\\\W=0.1\times 9.8\times 2\\W=1.96\ J[/tex]
So, the required work done is 1.96 J.
(Cr(NH3).](Co(CN)6) is a coordination complex
compound. What is the percent composition of carbon in this
compound?
Answer:19.51%
Explanation:
The least penetrating form of radiation is
X rays
gamma radiation
ОООО
alpha radiation
beta radiation
Answer:
radio radiation........
Answer
C.( Alpha particles!
Which pair of moving pulses in a rope will produce
destructive interference?
Help Easy Question and Brainly. What's the answer?????
Answer:
negatively
Explanation:
Answer:
Negatively charged
Explanation:
PLS ANSWER MY QUESTION TOO
What is the speed of a rocket that travels 9,000 meters in 12 seconds?
You are in a car traveling at 20 m/s. An ambulance is behind you traveling 35 m/s in the same direction. What frequency do you hear if the siren has a frequency of 550 Hz?
Answer:
The frequency heard is 576.78 Hz
Explanation:
The Doppler effect is defined as the apparent frequency change of a wave produced by the relative movement of the source with respect to its observer. In other words, this effect is the change in the perceived frequency of any wave motion when the sender and receiver, or observer, move relative to each other.
This is what happens in the first part of this problem, where the sender is train A and the receiver is train B. They are both moving in opposite directions. In this case, where both are in motion, the frequency perceived by the receiver will increase when receiver and transmitter increase their separation distance and will decrease whenever the separation distance between them is reduced. The following expression is considered the general case of the Doppler effect:
[tex]f'=f*\frac{v+-vR}{v+-vE}[/tex]
Where:
f ', f: Frequency perceived by the receiver and frequency emitted by the issuer respectively. Its unit of measurement in the International System (S.I.) is the hertz (Hz), which is the inverse unit of the second (1 Hz = 1 s-1)
v: Velocity of propagation of the wave in the medium. It is constant and depends on the characteristics of the medium. In this case, the speed of sound in air is considered to be 343 m / s
vR, vE: Speed of the receiver and the emitter respectively. Its unit of measure in the S.I. is the m / s
±, ∓:
We will use the + sign:
In the numerator if the receiver approaches the emitter In the denominator if the emitter moves away from the receiverWe will use the sign -:
In the numerator if the receiver moves away from the emitter In the denominator if the emitter approaches the receiverIn this case you are in a car traveling at 20 m/s and an ambulance is behind you traveling 35 m/s in the same direction.
In this case the receiver, you in the car, moves away from the emitter, while the emitter, the ambulance, approaches the receiver behind you in the same direction. So the frequency is calculated by the expression:
[tex]f'=f*\frac{v-vR}{v-vE}[/tex]
Being:
f= 550 Hzv=343 m/svR= 20 m/svE= 35 m/sand replacing:
[tex]f'=550 Hz*\frac{343 m/s-20 m/s}{343 m/s-35 m/s}[/tex]
you get:
f'= 576.78 Hz
The frequency heard is 576.78 Hz
Why does the moon appear to change its shape as seen from Earth
A.Different parts of the sunlit moon become visible as the moon revolves around the Earth
B.Different parts of the moon are lit as the moon rotates
C.The moon moves farther and then closer to Earth
D.The sun lights different parts of the moon during different seasons
Answer:
Explanation:
Why does the moon appear to change its shape as seen from Earth
Which experiment proved light was a wave?
A) Photoelectric effect
B) Double Slit
C) Compton Scattering
D Light was never proved to be a wave
Answer:
The answer is B) Double slit