Answer:
3
Explanation:
Name the part of the human eye which acts as a protective layer for the eye
Answer:
Cornea
Explanation:
Cornea protects outer layer of the eye.
QUESTION 2
At the end of an investigation, what should be done if the results do NOT support the hypothesis?
O A Repeat your investigation to ensure your results are accurate and then modify your hypothesis if necessary.
OB. Repeat your investigation over and over again until you get the results that will support your original hypothes
O C. Check your measurement tools to ensure they are working.
OD. Change the topic of your investigation to one that will yield results that support a hypothesis.
Answer:
A. Repeat your investigation to ensure your results are accurate and then modify your hypothesis if necessary.
Explanation:
Having results that do not support the hypothesis is a common occurrence.
Hypotheses always depend on the data and experiment. If at the end of an investigation the results do not support the hypothesis, the investigation should be be repeated to further confirm this discovery.
And if there is still no correlation, then the hypothesis is not a reasonable explanation for the investigation and should be modified or rejected if necessary.
which two types of information are found in an elements box in the periodic table
Answer:
Each box represents an element and contains its atomic number, symbol, average atomic mass, and (sometimes) name.
Explanation:
Answer:
An element's period and group
I need help with this please
A 30%-efficient car engine accelerates the 1300 kg car from rest to 10 m/s . How much energy is transferred to the engine by burning gasoline
Answer:
The Energy transferred to the engine by burning gasoline = 216.67 KJ
Explanation:
The parameters given are:
The efficiency of the car engine, E = 30% = 0.3
Mass, m = 1300 kg
Initial velocity, u = 0, since the car is from rest
The final velocity, v = 10 m/s
Since the car was moving, we calculate its kinetic energy.
kinetic energy = ((1/2) (m) (v^2)
((1/2) (1300 kg) (10 m/s^2)
= 65,000 j
The Energy, Q transferred to the engine by burning gasoline in this case
= potential energy / The efficiency of the car engine, E
Q = 65,000 j / 0.3
= 216,666.66 J
Converting Joule to kilojoule
where 1KJ = 1000j
216,666.66 J = 216.67 KJ
According to Newton's first law, which characteristic of a moving object would remain constant if there were no other
forces acting on it?
O size
c
mass
O shape
O speed
Mark this and return
Save and Exit
NIKKI
Submit
What is the change in internal energy (in J) of a system that absorbs 0.523 kJ of heat from its surroundings and has 0.366 kcal of work done on it
Answer:
The change in internal energy of the system is 2,054 J
Explanation:
The first law of thermodynamics relates the work and the transferred heat exchanged in a system through internal energy. This energy is neither created nor destroyed, it is only transformed.
Taking into account that the internal energy is the sum of all the energies of the particles that the system has, you have:
ΔU= Q + W
where U is the internal energy of the system (isolated), Q is the amount of heat contributed to the system and W is the work done by the system.
By convention, Q is positive if it goes from the environment to the system, or negative otherwise, and W is positive if it is carried out on the system and negative if it is carried out by the system.
In this case:
Q= 0.523 kJ (because the energy is absorbed, this is,it goes from the environment to the system)W= 0.366 kcal= 1.531 kJ (because the work is done on the system, and being 1 kcal= 4.184 kJ)Replacing:
ΔU= 0.523 kJ + 1.531 kJ
Solving:
ΔU= 2.054 kJ = 2,054 J (being 1 kJ=1,000 J)
The change in internal energy of the system is 2,054 J
A person has a mass of 1000g and an acceleration of 20 m/s/s. What is the force on the person
Answer:
20000
Explanation:
Newtons Second law states that the force acting on an object is equal to its mass times its acceleration, f=ma. To solve for force, plug in your values for m and a, and then solve. f = (1000)*(20) = 20000
1. According to its computer, a rocket launched
traveled 1200 m, had an average speed of 100.0
m/s. How-long did the trip take?
Answer:
I think it's = 12 seconds
Explanation:
the formula for speed is:
speed=[tex]\frac{distance}{time}[/tex] SO, time is equal to:
time=[tex]\frac{distance}{speed}[/tex]
(sub the numbers in the formula)
distance=1200m, speed=100m/s
time=[tex]\frac{1200}{100}[/tex]
=12 seconds
In a lightning bolt, a large amount of charge flows during a time of 1.2 x 10-3 s. Assume that the bolt can be represented as a long, straight line of current. At a perpendicular distance of 21 m from the bolt, a magnetic field of 8.4 x 10-5 T is measured. How much charged has flowed during the lightning bolt?
Answer: 10.58 C has flowed during the lightning bolt
Explanation:
Given that;
Time of flow t = 1.2 × 10⁻³
perpendicular distance r = 21 m
Magnetic field B = 8.4 x 10⁻⁵ T
Now lets consider the expression for magnetic field;
B = u₀I / 2πr
the current flow is;
I = ( B × 2πr ) / u₀
so we substitute
I = ( (8.4 x 10⁻⁵) × 2 × 3.14 × 21 ) / 4π ×10⁻⁷
= 0.01107792 / 0.000001256
= 8820 A
Hence the charge flows during lightning bolt will be;
q = It
so we substitute
q = 8820 × 1.2 × 10⁻³
q = 10.58 C
therefore 10.58 C has flowed during the lightning bolt
7N
6
→ 2N
Net Force:
Determine the net force acting on the object.
Answer:
When a force is applied to the body, not only is the applied force acting, there are many other forces like gravitational force Fg, frictional force Ff and the normal force that balances the other force. Therefore, the net force formula is given by, FNet = Fa + Fg + Ff + FN.
Explanation:
Marisa’s car accelerates at an average rate of 2.6m/s^2. Calculate how long it takes her car to accelerate from 24.6m/s to 26.8m/s? Show your work.
given info is... Acceleration(a)=2.6m/s^2
final velocity(v)=26.8m/s
initial velocity(u)=24.6m/s
need to find.... time(t)=?
[tex]a=\frac{v-u}{t} \\2.6=\frac{26.8-24.6}{t} \\\\[/tex]
[tex]t=\frac{v-u}{a}[/tex]
[tex]t=\frac{26.8-24.6}{2.6}[/tex]
[tex]t=0.846s[/tex]
Explanation:
It takes 0.84 second her car to accelerate from 24.6m/s to 26.8m/s.
What is acceleration?Acceleration is the rate at which speed and direction of velocity vary over time. A point or object going straight ahead is accelerated when it accelerates or decelerates. Even if the speed is constant, motion on a circle accelerates because the direction is always shifting.
Given parameters:
Initial speed of the car: u = 24.6 m/s
Final speed of the car: v = 26.8 m/s.
Acceleration of the car: a = 2.6 m/s²
Time interval: t = ?
change is speed = final speed - initial speed
= 26.8 m/s - 24.6 m/s
= 2.2 m/s
From the definition of acceleration,
acceleration = change is speed / time interval
So, time interval = change is speed / acceleration
= 2.2 m/s/2.6 m/s²
= 0.84 second.
Hence, it takes 0.84 second her car to accelerate from 24.6m/s to 26.8m/s.
Learn more about acceleration here:
brainly.com/question/12550364
#SPJ2
A .05 kg rubber ball is dropped and hits the floor with an initial velocity of 10 m/s. It rebounds away from the floor with a final speed of 7 m/s after being in contact with the floor for .01 seconds. Find the magnitude of the force exerted by the floor on the rubber ball.
Answer:the answer is 3
Explanation:
g An angry rhino with a mass of 2700 kg charges directly toward you with a speed of 3.70 m/s. Before you start running, as a distraction, you throw a 0.180 kg rubber ball directly at the rhino with a speed of 9.05 m/s. Determine the speed of the ball (in m/s) after it bounces back elastically toward you.
Answer:
9.05m/s
Explanation:
given data
m1= 2700kg
v1=3.7m/s
m2=0.18kg
v2=9.05m/s
v3=?
We know that the velocity of the rhino will remains unchanged after impact as the mass of the rubber ball is negligible
m1v1+m2v2=m1v1+m2v3
2700*3.7+0.18*9.05=2700*3.7+0.18*v3
9990+1.629=9990+0.18v3
9991.629-9990=0.18v3
1.629=0.18v3
v3=1.629/0.18
v3=9.05m/s
It took 50 joules to push a chair 5 meters across the floor. With what force was the chair pushed?
Answer:
The chair was pushed with 10 N.
Explanation:
The chair was pushed with 50 Joules.
Work = Force * Distance
50 J = F * 5m
F = 50 / 5 = 10N
The chair was pushed with 10 N.
The chair was pushed with 10 N force.
What is Work done?Work is defined as the measure of energy transfer that occurs when an object is moved over a distance by an external force, at least part of which is applied in the direction of displacement.
If the force is constant then work can be calculated by multiplying the length of the path by the component of the force acting along the path, which is expressed mathematically as work W equal to the force f over a distance d, or W = fd.
So, for above given information,
Work done= 50 joules
Distance covered by the chair = 5m
Then, Force= W/d
=50/5= 10N
Thus, the chair was pushed with 10 N force.
Learn more about Work done, here:
https://brainly.com/question/13662169
#SPJ2
The coefficient of static friction between m1 and the horizontal surface is 0.50, and the coefficient of kinetic friction is 0.30. (a) If the system is released from rest, what will its acceleration be
This question is incomplete
Complete Question
m1 is 10kg, m2 is 4.0kg. The coefficient of static friction between m1 and the horizontal surface is 0.50. and the Coefficient of kinetic friction is 0.30.
a) if the system is released from rest what will be its acceleration
Answer:
0.7 m/s²
Explanation:
The coefficient of static friction between m1 and the horizontal surface is 0.50. and the coefficient of kinetic friction is 0.30.
(a) if the system is released from rest what will be its acceleration
g = acceleration due to gravity = 9.81 m/s²
Coefficient of Kinetic Friction = μk = 0.30
m1 = 10kg
m2 = 4.0kg
The formula to solve question a is given as:
a = acceleration at rest
m2g- μk m1g = (m1+ m2) a
Making a the subject of the formula:
a = (m2g- μk×m1g )/(m1+ m2)
a = [(4.0 kg × 9.81m/s²) – (0.30 ×9.81 × 10) ]/(10+4)
a = 0.7 m/s²
plzzz helppp
You are pushing a box North in the hallway, at 20n, and a friend gets in front of the box and goes in the opposite direction, at 30n. What direction is the box going at? How much force does the box have going in that direction?
Answer:
the box is going south at 10n
Explanation:
If 0.5 kg of this material is used in a transformer core, how long would it have to operate at a frequency of 60 cps to heat up 1
Answer:
Hello your question is incomplete attached below is the complete question
answer : 49 seconds
Explanation:
considering only Hysteresis loss
we have to calculate the Area affected/under the Hysteresis loss
= volume * area
= 4 * ( 1.5 * 20 ) = 120 tesla. A/m
next we calculate the volume of the material
= mass of material / density
= 500 grams / 7.9 g/cm^3 = 6.33 * 10^-5 m^3
next we calculate the heat lost per cycle
= 6.33 * 10^-5 m^3 * 120 = 0.007596 joules
The total heat required to raise temperature by 1°c
= Cp * ΔT * n
= 3R * n * ΔT = 3(8.314) * 8.95 * 1 = 223.23 Joules
where n = number of moles = 500grams / 55.85 = 8.95moles
ΔT = 1
Therefore the time required to have to operate at a frequency of 60 cps
= Total heat required / heat lost per cycle
=( 223.23 / 0.007596 ) 60 cps
= 489.796 seconds ≈ 49 seconds
Silly Goose falls 1.0 m to the floor. How long does the fall take
Answer:You need to give more explanation sorry
Explanation:
Answer:
4.20 seconds
Explanation:
Supposing that silly goose weighs 69 pounds, we need to start on the math.
Simple maths, truly and really. 69/1=69, of course.
Therefore it will take 4.20 seconds for silly goose to hit the ground. if he is going to be a silly goose though, he can just go in the pond, instead of wasting his time.
Can someone please help me with this following question, If you could visit Pangaea what animals would you find
A). Penguins
B). Mammals
C). Dinosaurs
D). Eagles
Answer:
C). Dinosaurs
Explanation:
A dog has a mass of 60kg and an acceleration of 2m/s/s. What is the force of the dog?
What is the net force acting on the piano?
0 11,500 N
0 -11,500 N
0 500 N
0 -500 N
Answer:
500
Explanation:
The net forces should be subtracted, so the number would be 500 N.
Answer:
the net force acting on the piano is -500N.
Explanation:
In this diagram two opposite forces are acting.There net force will be[tex]F=F_{g} -F_{t} \\F=5,500-6,000\\F=-500N[/tex]
negative sign shows that the force is acting in the upwards direction.What is force?An external agent that can change, shape, size, position, and direction is called force.
https://brainly.com/question/26115859
#SPJ2
An object is rolled at 12 m/s down a table. It stops
after 15s. What was its acceleration?
Variables:
Equation and Solve:
Answer:
We are given:
initial velocity (u) = 12 m/s
final velocity (v) = 0 m/s
time taken (t) = 15 seconds
acceleration (a) = a m/s²
Solving for acceleration:
from the first equation of motion
v = u + at
replacing the variables
0 = 12 + (a)(15)
0 = 15a + 12
a = -12 / 15
a = -4 / 5 m/s²
Plates slide past one another at____.
A. Subduction zones
B. Transform boundaries
C. Convection currents
D. Divergent boundaries
Answer:
Transform Boundary
Explanation:
The just slide past each other
Answer:
Transform Boundaries
Explanation:
distance is constant and time increseas
Will Speed increase or decrease?
Answer:
The speed will be decrease
A block of mass m begins at rest at the top of a ramp at elevation h with whatever PE is associated with that height. The block slides down the ramp over a distance d until it reaches the bottom of the ramp. How much of its original total energy (in J) survives as KE when it reaches the ground
This question is incomplete, the complete question is;
A block of mass m begins at rest at the top of a ramp at elevation h with whatever PE is associated with that height. The block slides down the ramp over a distance d until it reaches the bottom of the ramp.
How much of its original total energy (in J) survives as KE when it reaches the ground? m = 9.9 kg h = 4.9 m d = 5 m μ = 0.3 θ = 36.87°
Answer:
the amount of its original total energy (in J) that survives as KE when it reaches the ground will is 358.975 J
Explanation:
Given that;
m = 9.9 kg
h = 4.9 m
d = 5 m
μ = 0.3
θ = 36.87°
Now from conservation of energy, the energy is;
Et = mgh
we substitute
Et = 9.9 × 9.8 × 4.9
= 475.398 J
Also the loss of energy i
E_loss = (umg cosθ) d
we substitute
E_loss = 0.3 × 9.9 × 9.8 × cos36.87° × 5
= 116.423 J
so the amount of its original total energy (in J) that survives as KE when it reaches the ground will be
E = Et - E_loss
E = 475.398 J - 116.423 J
E = 358.975 J
Which exerts more force, the Earth pulling on the moon or the moon pulling on the Earth? Explain.
Answer: the earth
Explanation: Earth exerts a gravitational pull on the moon 80 times stronger than the moon's pull on the Earth. Over a very long time, the moon's rotations created fiction with the Earth's tugging back, until the moon's orbit and rotational locked with Earth.
and that's why the earth pulls the moon
D
5. Mariam driving at a speed of 20.0 m/s applies
brakes close to a signal and travels a distance of
200 m before coming to rest. What was her
acceleration?
A. -0.50 m/s2
B. -0.70 m/s2
C. -1.00 m/s2
D. -2.00 m/s2
6. A trollen at rest is nushed to accelerate at a
Answer:
maibi.... D
Explanation:
I think is D
Examine the diagram below.
Which of the above objects is moving the fastest?
A.
All 3 objects are moving at the same speed.
B. B
C. C
D. A
Answer:
Correct choice: D. Object A is the fastest
Explanation:
In a distance vs time graph, the distance is plotted vertically, and the time is plotted horizontally.
The diagram shows three graphs of objects A, B, and C.
The graph of A shows the object traveled 12 meters in 3 seconds, for a speed of 12/3= 4 m/s.
The graph of B shows the object traveled 8 meters in 4 seconds for a speed of 8/4=2 m/s.
Finally, the object C travels 4 meters in 4 seconds, for a speed of 4/4= 1 m/s
Thus, the fastest object is A.
Grass and plants get energy from
А
the sun.
B
eating food.
с
windmills.
D
electrons.
Answer:
From the Sun
Explanation:
Plants can't eat any food. They don't ue or need windmills to get energy. They are plants so they don't have any electrons. The only way that they can recive energy from is the sun. Sometimes plants die when they don't get enough sun because they don't have any energy to live.