Answer:
the work converted to thermal energy is 40 J.
Explanation:
Given;
work done by the physicist,w = 100 J
height through which the book is raised, h = 0.2 m
efficiency of machine = 60% = 0.6
The useful work done by the machine is calculated as;
useful work = 0.6 x 100 = 60 J
The wasted energy = 100 J - 60 J
The wasted energy = 40 J
The wasted energy by the machine is possibly converted to thermal energy by the frictional part of the machine.
Therefore, the work converted to thermal energy is 40 J.
BRAINLEST FOR CORRECT ANSWER
Which has more momentum: a 3 kg sledgehammer swung at 1.5 m/s OR a 4 kg sledgehammer swung at 0.9 m/s? SHOW YOUR WORK FOR BRAINLEST
Answer:
3kg sledgehammer swung at 1.5 m/s
Explanation:
Small Sledgehammer:
Mass:3.0
Velocity:1.5
MASS×VELOCITY=MOMENTUM
3.0×1.5= 4.5 (momentum)
Large Sledgehammer:
Mass:4.0
Velocity:0.9
4.0×0.9=3.6 (momentum)
higher momentum is the smaller Sledgehammer.
Why do other stars look much dimmer than the sun?
What happens when weathering and erosion work together?
A. New mountains are created
B. The climate changes overnight
C. Metal objects become rusty
D. They change the earths surface
Plssss help
Answer:
A. New mountains are created
In some areas, hydroelectric power is not geographically appropriate and a different renewable energy source would be a better option. A conservation group is looking for renewable energy sources other than hydroelectric energy that could be used to generate electricity in grassland ecosystems, such as in the midwestern United States or in a savanna in Africa.
Required:
a. Propose a different renewable resource to use that would be a realistic solution to generating electricity without using fossil fuels or hydroelectric power in a grassland ecosystem.
b. Justify the solution proposed above by explaining a potential advantage of using a different renewable resource to generate electricity.
Answer:
a) wind power system, turbines powered, solar power system
b) the possibility of creating jobs for the local workforce and of maintaining the environment without damaging it.
Explanation:
In a grassland system it may not have great changes in height or mountain system where it is easy to represent a river, therefore a hydroelectric power system is not very feasible.
a) You can have several alternative energy systems.
* If there is a fairly constant air current, a wind power system could be implemented.
* If there is a river with an acceptable flow, a generation system can be implemented with turbines powered by the river flow.
* Another system is a solar power system
b) To select any of the possible systems proposed, the current and future energy requirements of the region must be analyzed.
The amount of energy that each proposal can supply
Analyze the installation costs and the economic benefits of a given system.
Study the possible problems for the maintenance of each system.
A great advantage of these systems is the possibility of creating jobs for the local workforce and of maintaining the environment without damaging it.
The most plausible renewable energy source in a grassland is wind energy.
Renewable energy refers to energy that is obtained from wind, water biomass or underground heat. All of these sources of energy are inexhaustible and hold great prospect to solving the current energy deficit is many parts of the world.
In grasslands, the most plausible renewable source of energy is wind. Winds are abundant in grasslands . It is more plausible than hydroelectric power because it does not create any adverse environmental impact. It is the cleanest energy source.
Learn more about renewable energy: https://brainly.com/question/4038933
2. The motion of roller coasters depends upon the conversion of potential
and kinetic energy. A 200 kg car starts from rest at the top of a hill with a
height of 30 m.
Which of the following is this car's kinetic energy at the bottom of the hill?
Answer:
58,800 Joules
Explanation:
I used the formula for Potential energy which is PE = mgh
200 kg x 9.8 m/s^2 x 30 m = 58,800 J
At the very tops of the rollercoaster is maximum PE which is 58,800 J and 0 J of KE, but at the very bottom is maximum KE (kinetic energy) which is 58,800 Joules but 0 J of PE. This is because energy can not be destroyed ONLY converted
17. The four points built into the camera to ensure that each exposure can be oriented
to the camera calibration are called?
A.
Nodal points
B.
Focal points
C. Focus
D. Fiducial marks
E. None of the above
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a.) the hunter
b.) Pole Star
c.) little bear
d.) pattern of stars
e.) nearest star
Plz help :> <3
Answer:
E
Explanation:
Gravitational potential energy is
O the energy that an object has when it is at a
certain elevation, h
the energy of an object at rest
O the energy that an object has because it is in
motion
The cnone of the above
pressure, V is volume , T is temperature of a gas and R is gas constant.
b) Can the sum of two equal vectors be equal to either of the vectors?
Explain
16. An object with a mass of 20.0 kg has a force of 5.0 newtons applied to it. What is the resulting acceleration of the object?
Answer:
0.25m/s^2
Explanation:
F = ma
a = F/m
(Newton's Second Law)
At which location does a skateboarder have the most kinetic energy at least potential energy?
Answer:The skater has the lowest amount of kinetic energy at the top of the track and lowest potential energy at the lowest point of the track. Kinetic energy is the speed a object is going, and potential energy is the energy a object has when its not moving. While the skater moves up the ramp the potential energy increases, and the kinetic energy decreases because it slows down while moving up the ramp. Hope this helps have a nice day ❤️
Explanation:
First recognize that the total energy of the skater is conserved: this means that the total energy of the skater is constant. The total energy (E) consists of the kinetic energy (KE) and gravitational potential energy (Ug).
E=KE+Ug
Now we know that the gravitational potential energy depends on the distance from the zero of potential (or in simpler terms: how high the skater is from the ground). Now, we are ready to answer the question.
The skater possesses the most KE at point B: remember total energy is a constant and at point B the skater has the least amount of potential energy (since they are at their lowest point above the ground). This means that the skater must have more kinetic energy at point B.
Similarly, at points A and C, the skater possesses the most potential energy since they are at their highest point above the ground.
As the skateboarder moves then it will have the maximum kinetic energy at the lower most portion of the track and will have the zero potential energy at the same point and at the maximum height of the track the skater will have maximum potential energy and zero kinetic energy.
What will be the KE and PE of the skater at maximum and minimum positions of the track?As the skater moves on the track his kinetic and potential energy converts into each other but the total energy remains constant.
Total Energy = KE+PE
At maximum height the kinetic energy will totally convert into the potential energy and becomes zero.and the potential energy becomes maximum at this point.
At Max height (Total energy=Max Potential energy) KE=0
Similarly at the lower most portion of the track the Potential energy completely convert into the kinetic energy and becomes zero. And kinetic energy becomes max at this point.
At lower point (Total energy= Max Kinetic Energy) PE=0
Thus the skater will have the most kinetic energy at the lower most point of the track and least potential energy at the same point.
To know more about energy follow
https://brainly.com/question/1634438
convertion of unit 8.28x10^-2ft m
Answer:
yes
Explanation:
no
Weight is the amount of matter in an object.
True or False
Answer:
False
Explanation:
The mass of an object is normally known as the weight of the object. but mass is the amount of matter in the object. Weight is the force exerted on an object by gravity
Answer: False
Explanation: mass is the amount of matter in an object
A body of mass 11 kg is subjected to a net force of 20 N East for 30 s. Calculate the change in
velocity of the body.
Answer:
54.55 m/s
Explanation:
From the question above,
Change in velocity = impulse/mass
Δv = I/m = Ft/m................... Equation 1
Where F = force, t = time, m = mass
Given: F = 20 N, t = 30 s, m = 11 kg
Substitute these values into equation 1
Δv = (20×30)/11
Δv = 600/11
Δv = 54.55 m/s
Hence the change in velocity of the body is 54.55 m/s
The change in velocity of the body is 54.54 m/s
The velocity of the body of an object is the change of the distance of the object with time.
From the information given:
the mass of the b0dy = 11 kg
the net force F = 20 N
the time (t) = 20 s
Similarly;
Force = ma
20 = 11 × (a)
[tex]\mathbf{a = \dfrac{20}{11} \ m/s^2}[/tex]
a = 1.818 m/s²
However, the acceleration of an object is the change in velocity with time.
[tex]\mathbf{a = \dfrac{\Delta V}{t}}[/tex]
ΔV = (a) × (t)
ΔV = 1.818 m/s² × 30 s
ΔV = 54.54 m/s
Learn more about the velocity of an object here:
https://brainly.com/question/626479
What are the key features of stem cell therapy?
Answer:
The two defining characteristics of a stem cell are perpetual self-renewal and the ability to differentiate into a specialized adult cell type.
Answer:
Stem cells have the ability to differentiate into specific cell types. The two defining characteristics of a stem cell are perpetual self-renewal and the ability to differentiate into a specialized adult cell type.
The equation for centripetal force can be derived by substituting the equation for centripetal acceleration into Newton’s second law.
Please select the best answer from the choices provided
T
F
Answer:
True.
Explanation:
Newton's Second Law of Motion states that the acceleration of a physical object is directly proportional to the net force acting on the physical object and inversely proportional to its mass.
Mathematically, it is given by the formula;
Force = mass * acceleration
[tex] F = ma[/tex]
Centripetal acceleration is given by the formula;
[tex] Acceleration, a = \frac {v^{2}}{r}[/tex]
Where;
v is the velocity.
r is the radius.
The equation for centripetal force can be derived by substituting the equation for centripetal acceleration into Newton’s second law.
Let centripetal force be Fc
Fc = ma
Substituting the value of "a" into the above formula;
[tex] Fc = m \frac {v^{2}}{r} [/tex]
[tex] Fc = \frac {mv^{2}}{r} [/tex]
In a
boundary, the more dense
plate will move below the less dense plate
when the plates collide.
A. transform
B. divergent
C. convergent
there is a metal ball and ring set that is specially made so that at room temperature at the ball fits through the ring However when the ball is heated it gets stuck and cannot fit through anymore .why
Answer: Most objects expand when they take in heat for example get a metal sphere and put it next to a blow torch it would expand just enough to not fit in the ring anymore, but when it cools down it will go back to its original size releasing the energy
Explanation:
A pendulum is swimging. It swings 85 complete swings and this takes 102 seconds. What is the frequency?
Answer:
0.833 Hz
Explanation:
While, there are plenty of ways to calculate frequency, the one formula you should use in this case is:
#times/seconds --> 85/102
= 0.833 Hz
How are particles behaving in solid vs gas when it comes to sound?
Answer:
Sound waves have to travel through solids, gases, and liquids. Sound waves vibrate through the air in matter. Molecules in solids are packed tightly. This allows sound to travel faster through a solid than gas.
1. A Zambeef delivery track travels 18 km north, 10 km east, and 16 km south. What is its final displacement from the origin?
Answer:
10.2 km
Explanation:
Displacement is the shortest distance from your original position after movement.
Now, the Zambeef delivery truck moves 18 km north and then 10 km east and then 16 km south.
This means that vertically the truck is 2km short of the 18 km he travelled north..
So we can find the displacement using pythagoras theorem..
Let d be the distance from the current position to the initial position.
Thus;
d² = 2² + 10²
d² = 4 + 100
d = √104
d ≈ 10.2 km
I have attached a diagram showing the direction of this displacement
Describe how a radiation is similar to b- radiation
Complete question is;
Describe how α-radiation is similar to β-radiation?
Answer:
Explained below
Explanation:
The similarity between both alpha radiation and beta radiation is that in both cases, they both show deflection when they go through electric and magnetic fields. Although alpha deflects towards the negative plate while bets deflects towards the positive plate.
Secondly they both have high speeds. Just that alpha is from the helium nucleus while beta is from electrons.
On Earth, what can a divergent boundary
cause?
A. An iceberg
B. A plateau
C. A rift valley
Answer: C
Explanation:
Divergent plate boundary is a linear feature that exists between two tectonic plates that are moving away from each other. Divergent boundaries within continents initially produce rifts, which eventually become rift valleys. Most active divergent plate boundaries occur between oceanic plates and exist as mid-oceanic ridges.
While hammering a nail, you put in 30 Joules of work. The hammer then puts out 10 J of
work on the nail. What is that hammer's efficiency?
A. 300%
B. 40%
С. 33%
D. 33 J
Answer:
C Don't worry if you thought it was D. I almost answered that.
Explanation:
Remark
You can get this just by learning the vocabulary.
Efficiency = Work Out / Work In * 100%
Work in = 30J That's you swinging the hammer.
Work out = 10 J That's how much of the hammer's work gets to the nail.
Efficiency = (10/30)*100
Efficiency = 1/3 * 100
Efficiency = 33%
Answer:
I think its 40%, pls correct me if I am wrong :(
Explanation:
A 23cm hammer is used to pull a nail. If 42.5 N of force is applied to it at a 45° angle, how much torque is applied?
Answer:6.91 Nm
Explanation:
When conducting research,
are unintentional factors that creep into your experiment and have the potential to affect or even spoil your results.
a. confounding variables
b. replication digits
c. extrapolating factors
d. independent variables
Answer:
a. confounding variables.
Explanation:
An experiment can be defined as an investigation which typically involves the process of manipulating an independent variable (the cause) in order to be able to determine or measure the dependent variable (the effect).
This ultimately implies that, an experiment can be used by scientists to show or demonstrate how a condition causes or gives rise to another i.e cause and effect, influence, behavior, etc in a sample.
In an experiment , the variable being manipulated by an experimenter is known as an independent variable while the dependent variable is the event expected to change when the independent variable is manipulated.
A confounding variable can be defined as a variable that generally influences both the independent and dependent variable in an experiment or research study. Thus, it creates an association between the two variables in an experiment.
Hence, when conducting research, confounding variables are unintentional factors that creep into your experiment and have the potential to affect or even spoil your results.
Which circuit would have the most electrical power?
Answer:
c
Explanation:
Newtons 1st law
What is the resistance to this unbalanced force in football?
Answer:
Newton's first law of motion states that an object's motion will not change unless an unbalanced force acts on the object. ... The football player in the photo above is in motion. He will stay in motion unless players on the other team exert an unbalanced force against him.
Explanation:
https://flexbooks.ck12.org/cbook/ck-12-middle-school-physical-science-flexbook-2.0/section/1.4/related/rwa/football-physics/
LINK
Disadvanlayes and advantager of the and A and B
Answer:
Advantages
If there is a fault in one of the electric appliances, the current is able to pass through different paths of the circuit.
Disadvantages
In parallel circuits, we cannot increase the voltage since the resistance decreases in the parallel circuit.
Explanation:
Calculate the gravitational pull between the Earth and the Moon
Answer:
F = 1.99 10²⁰ N
Explanation:
The gravitational attraction is given by the expression
F = [tex]G \ \frac{m_1m_2}{r^2}[/tex]
where G is the constant of attraction 6.67 10⁻¹¹ N m²/kg²
in this case the bodies are the Earth and the Moon
let's calculate
F = [tex]6.67 \ 10^{-11} \ \frac{ 7.36 \ 10^{22} \ 5.98 \ 10^{24} }{ (3.84 \ 10^8)^2}[/tex].67 10⁻¹¹ 7.36 10 22 5.98 1024 / (3.84 108) 2
F = 1.99 10²⁰ N