Answer: Alkali metals
Soft, Extremely reactive, 1 valence electron
Alkaline earth metals
Harder, more dense, 2 valence electrons
Answer:Alkali metals
Soft, Extremely reactive, 1 valence electron
Alkaline earth metals
Harder, more dense, 2 valence electrons
Explanation:
THE PERSON ABOVE ME IS CORRECT IM JUST PUTTING THIS HERE SO YOU KNOW I GOT 100% BECAUSE OF THAT PERSON THANK YOU
What is the kinetic energy of a bicylcle with a mass of 15 kg traveling at a velocity of 3 m/s?
KE = 0.5 x mv^2
Kinetic energy equals 1/2 times mass times velocity squared.
Mass = 15kg
Velocity = 3m/s
Plug it into the formula.
KE = 0.5 x 15(3^2)
KE = 0.5 x 15(9)
Multiply the mass and velocity squared.
KE = 0.5 x 135
Then, multiply the result by 1/2 or 0.5
KE = 67.5
The kinetic energy of a bicycle that has a mass of 15kg and travels at 3m/s is 67.5J.
Answer:
67.5 J
Explanation:
Kinetic energy can be found using the following formula.
[tex]KE=\frac{1}{2}mv^2[/tex]
where m is the mass in kilograms and v is the velocity in m/s.
We know the bike has a mass of 15 kilograms. We also know the velocity is 3 m/s. Therefore, we can substitute 15 for m and 3 for v
[tex]KE=\frac{1}{2}*15*3^2[/tex]
Evaluate the exponent first. 3^2 is the same as 3*3, which is equal to 9.
[tex]KE=\frac{1}{2} *15*9[/tex]
Multiply 15 and 9.
[tex]KE=\frac{1}{2} *135[/tex]
Multiply 1/2 and 135
[tex]KE=67.5[/tex]
Add appropriate units. Kinetic energy uses Joules or J as the units.
[tex]KE= 67.5 Joules[/tex]
The kinetic energy of the bike is 67.5 Joules
Which triangle side lengths form a right triangle? Choose all that apply.
A. 5,6,7
B. 6,8,14
C. 8,15,17
D. 10,12,15
E. 15,20,25
F. 16,18,20
Identify the magnetic north pole of Earth’s magnet?
Answer:
using magnets
Explanation:
If we hang a magnet with a rope to an object the north pole of the magnet will point to the Earth's north pole
Which phrase correctly describes ice?
A) Rigid and having low viscosity
B) Crystalline and having high surface tension
C) Amorphous and having low viscosity
D) Crystalline and rigid
Answer: D) Crystalline and rigid
Explanation:
Ice is considered to be a rigid mineral. It possesses a regular crystalline structure based on the molecule of water, which consists of a single oxygen atom covalently bonded to two hydrogen atoms, or H–O–H.
Answer: D
Explanation:
According to Newton's second law, how are acceleration and mass related? Directly or indirectly when force is constant?
Answer:
Newton's second law of motion can be formally stated as follows. The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net Force in the same direction as the net force and inversely proportional to the mass of the object
Explanation:
The second law states that the acceleration of an object is dependent upon two variables - the net force acting upon the object and the mass of the object. The acceleration of an object depends directly upon the net force acting upon the object, and inversely upon the mass of the object. According to Newton's second law of motion, acceleration is directly proportional to force. As the force increases (when mass is constant), the acceleration increases
What is the focal length of a lens if an object placed 3.28 cm from the lens produces an image that is 4.11 cm in front of the lens?
Answer:
1.82 cm
Explanation:
The relationship between the object distance (p), image distance (q) and focal length (f) is given by [tex]\frac{1}{p}+\frac{1}{q}=\frac{1}{f}[/tex]
According to question,
Object distance (p) = 3.28 cm
Image distance (q) = 4.11 cm
Therefore,
[tex]\frac{1}{3.28}+\frac{1}{4.11}=\frac{1}{f}\\\frac{3.28+4.11}{3.28\times 4.11}=\frac{1}{f}\\f=\frac{3.28\times 4.11}{3.28+4.11}\\=\frac{13.48}{7.39}\\=1.82\,\,cm[/tex]
What is the speed of a high-speed electron traveling at right angles to a 0.80-tesla magnetic field with a force of -7.5 x 10^-12 newtons? The charge of an electron is 1.60 x 10^-19
Explanation:
Answer:
Magnetic field, B = 0.016 Tesla
Explanation:
It is given that,
Velocity of electron, v=9.6\times 10^5\ m/sv=9.6×10
5
m/s
Magnetic force, F=2.6\times 10^{-15}\ NF=2.6×10
−15
N
Charge, q=1.6\times 10^{-19}\ Nq=1.6×10
−19
N
The magnetic force is given by :
F=qvBF=qvB
B=\dfrac{F}{qv}B=
qv
F
B=\dfrac{2.6\times 10^{-15}}{1.6\times 10^{-19}\times 9.6\times 10^5}B=
1.6×10
−19
×9.6×10
5
2.6×10
−15
B=0.016\ TB=0.016 T
So, the magnitude of magnetic field is 0.016 Tesla. Hence, this is the required solution.
Answer:
F = q v B so v = F/q B
v = -7.5 × 10-12/(-1.60 × 10-19) (0.80) = 5.9 × 107 m/s
Explanation:
ASAP if you answer right I will mark brainiest....
Answer: *The inner planet that has two moons is Mars * the only planet in the Solar System with clockwise rotation is Venus * The surface of Mercury is covered with ancient magma ( which is similar to the spews of volcanoes on Earth as well) * The planet that is closest to Earth is Mercury * Venus has more volcanoes than any other planet * Earth's moon formed when a(n) can sometimes be called the Big Splash or can be called the Theia impact (Luna the moon formed from the ejecta of the collision between the Proto- Earth and Mars sized planet) * Mars is called the red planet because it's soil contains the element iron oxide ( which is the compound that gives blood and rust hue)
Explanation: Hope this helped :)
What does the law of conservation of energy state about energy in a closed system
Answer:
The total energy in a closed system (a system that isolated from its surroundings) is always constant.
Explanation:
The law of conservation energy states that:
The total energy in a closed system (a system that isolated from its surroundings) is always constant.
What this law means is that energy can never be created or destroyed but can only be converted from one form to another form or example the conversion of energy from potential energy to kinetic energy which is seen by a falling object from a height.
When the motion energy of an object changes, there is inevitably some other change in energy at the same time. If an object is slowing down, where is the energy going? (Check all that apply)
Question 9 options:
The potential energy could be increasing, like a ball thrown into the air.
The kinetic energy could be lost to friction or air resistance.
The ball could be returning to its natural resting state.
Due to the conservation of energy, the kinetic energy must stay the same.
Explanation:
This problem bothers on the conservation of mechanical energyThis is the principles in which the energy changes by virtue of the position of the body and when in motion are conserved.
The principle of conservation of mechanical energy states that "energy can neither be created nor destroyed but can be transformed from one form to another".
Based on the principle of energy conservation the correct options are
The potential energy could be increasing, like a ball thrown into the air.The kinetic energy could be lost to friction or air resistance.The ball could be returning to its natural resting state.A 100 kg bag of sand has a weight on 100 N. When dropped its acceleration is what?
Answer:
The acceleration of the bag of sand is [tex]1\ m/s^2[/tex].
Explanation:
We have,
Mass of a bag of sand is 100 kg
Weight of the bag of sand is 100 N
It is required to find the acceleration of the bag when it is dropped. The weight of an object is given by :
[tex]F =ma[/tex]
When it is dropped, a = g
[tex]g=\dfrac{F}{m}\\\\g=\dfrac{100}{100}\\\\g=1\ m/s^2[/tex]
So, the acceleration of the bag of sand is [tex]1\ m/s^2[/tex].
What did you notice about your muscles as you performed the combinations? Were there steps or movements that took more effort? Describe. How do you think your muscles supported your body? How do you think your muscles worked to help you move?
Answer:Muscles pull on the joints, allowing us to move. They also help the body do such things as chewing food and then moving it through the digestive system. Even when we sit perfectly still, muscles throughout the body are constantly moving.
Muscles move body parts by contracting and then relaxing. Muscles can pull bones, but they can't push them back to the original position. So they work in pairs of flexors and extensors. The flexor contracts to bend a limb at a joint.
Explanation:
The brakes on a bicycle apply 95 N of force to the wheels. When the
brakes are applied, the bicycle comes to a stop in 16 m. How much work
are the brakes doing on the wheels?
0 1,500
O 250 m
1,520 J
40 m/s
Answer:
Work done, W =1520 J
Explanation:
We have,
The brakes on a bicycle apply 95 N of force to the wheels. When the brakes are applied, the bicycle comes to a stop in 16 m.
It is required to find the work done by the brakes on the wheels. We know that the product of force and displacement is equal to the work done. It is given by :
[tex]W=Fd\\\\W=95\times 16\\\\W=1520\ J[/tex]
So, the work done by the brakes is 1520 J.
A ball has m=10 kg and v=10 m/s. It has the same momentum as which of the following?
Select one:
a. A ball with m = 100 kg and v = 1 m/s.
b. A ball with m = 5 kg and v = 20 m/s.
c. A ball with m = 2 kg and v = 50 m/s
d. all of these
Answer:
Choice d. All three balls listed in choice a, b, and c have a momentum of [tex]100\; \rm kg \cdot m \cdot s^{-1}[/tex] each, same as that of the [tex]10\; \rm kg[/tex] ball moving at [tex]10\; \rm m \cdot s^{-1}[/tex]. Assumption: all four balls are moving in the same direction.
Explanation:
The momentum [tex]p[/tex] of an object is equal to the product of its mass [tex]m[/tex] and its velocity [tex]v[/tex].
Momentum of a [tex]10\; \rm kg[/tex] ball moving at [tex]10\; \rm m \cdot s^{-1}[/tex]:
[tex]p = m \cdot v = 10\; \rm kg \times 10\; \rm m \cdot s^{-1} = 100\; \rm kg \cdot m \cdot s^{-1}[/tex].
Similarly:
Momentum of the ball in choice a: [tex]100 \; \rm kg \times 1\; \rm m \cdot s^{-1} = 100\; \rm kg \cdot m\cdot s^{-1}[/tex].Momentum of the ball in choice b: [tex]5 \; \rm kg \times 20\; \rm m \cdot s^{-1} = 100\; \rm kg \cdot m\cdot s^{-1}[/tex].Momentum of the ball in choice c: [tex]2 \; \rm kg \times 50\; \rm m \cdot s^{-1} = 100\; \rm kg \cdot m\cdot s^{-1}[/tex].Hence the conclusion that these balls have the same momentum.
Describe the relationship between the direction of the velocity vector and the direction of the acceleration for a body moving in a circle at constant speed.
Which of the following is an inclined plane?
- Stairs
- Wheelchair ramp
- Sloping driveway
- Road going up a mountain
Explanation:
Wheelchair ramp
An inclined plane, also known as a ramp, is a flat supporting surface tilted at an angle, with one end higher than the other, used as an aid for raising or lowering a load.
Television satellites use infrared waves to transmit. true or false
Answer: false
Explanation: Because Television satellites use microwaves waves to transmit.
Television satellites don't use infrared waves to transmit.
When a current flows through a light bulb, it emits 30 J light energy in 2 seconds, What is the power of the bulb?
The power of the light bulb is 15 watts.
What is power ?Power in physics is defined as the rate of energy per unit time or in other words the work done by any electrical appliance per unit time. Power is expressed as -
P = E/T where E is Energy and T is the time period.
How to calculate the value of power in the question ?Given that the light bulb emits 30 J light energy in 2 seconds.
We have E = 30J and T = 2 seconds.
Therefore power(P) = Energy(E) / Time(T)
∴ P = 30 / 2 = 15 watts
Thus the power of the light bulb is 15 watts.
To learn more about power in physics, refer -
https://brainly.com/question/11569624
#SPJ2
Which part of the human eye helps to focus light?
retina
pupil
iris
cornea
Answer:
lens my guess is iris
Explanation:
The Lens. The lens is composed of transparent, flexible tissue and is located directly behind the iris and the pupil. It is the second part of your eye, after the cornea, that helps to focus light and images on your retina.
The lens does most of the focusing.
The cornea helps too.
What of the following does NOT influence resistance? *
A.thickness of wire
B.temperature
C.material of wire
D.Number of components
Answer:
D. Number of components
Explanation:
Answer:
D. Number of components
Explanation: hope this helps :)
The surface of the moon always looks the same because the moon has no:
gravity
weather
running water
Carbon (C) and hydrogen (H) are pure substances. Each is made of only one type of atom, but carbon atoms are different from hydrogen atoms. Carbon and hydrogen chemically combine to form methane (CH4).
Carbon (C) and hydrogen (H) are pure substances. Each is made of only one type of atom, but carbon atoms are different from hydrogen atoms. Carbon and hydrogen chemically combine to form methane (CH4).
Based on this information,
A.
carbon and hydrogen are elements and methane is a compound.
A force of 310.0 N is used to push a 120 kg mass, 30.0 m horizontally in 3.00 s.
(a) Calculate the work done on the mass.
[ ] × kJ
(b) Calculate the power developed.
[ ] kW
Explanation:
We have,
Force acting on the mass is 310 N
Mass, m = 120 kg
Distance covered by the mass is 30 m
Time, t = 3 s
To find,
(a) Work done (b) power developed
Solution,
(a) The work done on the mass is given by the product of force and displacement such that,
[tex]W=Fd\\\\W=310\times 30\\\\W=9300\ J[/tex]
(b) The rate at which the work is done is called power developed. Its formula is given by :
[tex]P=\dfrac{W}{t}\\\\P=\dfrac{9300}{3}\\\\P=3100\ W[/tex]
Therefore, the work done on the mass is 9300 J and the power developed is 3100 W.
Which of the following statements concerning the scientific method is true?
Once a scientific law is formed, it cannot be changed.
Scientists must first draw a conclusion about a hypothesis and then find
experiments that always support the conclusion,
Scientists first develop a theory, which becomes à hypothesis if other scientists
want the idea to be tested.
Scientists form a hypothesis before conducting experiments and then the
experiments are used to draw a conclusion.
Answer:
Scientists form a hypothesis before conducting experiments and then the experiments are used to draw a conclusion.
Explanation:
FALSE: Once a scientific law is formed, it cannot be changed.
We are always willing to change if we find out we are wrong.FALSE: Scientists must first draw a conclusion about a hypothesis and then find experiments that always support the conclusion,
We must first test our hypothesis through experimentation and base our conclusion on the actual observation.FALSE: Scientists first develop a theory, which becomes à hypothesis if other scientists want the idea to be tested.
A theory starts as a hypothesis that is tested numerous times and found to be consistently true.TRUE: Scientists form a hypothesis before conducting experiments and then the experiments are used to draw a conclusion.
True.Determining Charge
An element becomes a positively charged ion when it
oloses protons.
loses electrons.
gains electrons
gains neutrons.
Answer:
hey friend,
an element becomes a positively charged ion when it loses electrons
Which of the following is NOT an important factor in selecting a medical professional?
A
cost
B accessibility
C. location
D
appearance
Please select the best answer from the choices provided
А
В
C
D
Answer:
D
Explanation:
appearance is not a imp factor . location could be imp. becoz a proper environment is need to study such courses.
Answer: D. appearance
Explanation:
With a bar magnet, where are lines of force the closest together?
A) At the tip of either of the magnet's poles
B) At a point outside the magnet halfway between the poles
C) Inside the center of the magnet
Answer:The lines of force in a magnet is closer together at the ends of a bar magnet.
Explanation:Is equally strong at the north pole when compared with the south pole. The force is weaker in the middle of the magnet and halfway between the pole and the center.
what is earths magnetism
Answer:
Magmatism is the emplacement of magma within and at the surface of the outer layers of a terrestrial planet, which solidifies as igneous rocks. ... On Earth, magma forms by partial melting of silicate rocks either in the mantle, continental or oceanic crust.
Explanation:
An isotope releases radiation in order to ____________ its nucleus.
stabilize
destroy
Answer:
stabilize
I think this should be the answer...
Answer stabilize
Explanation: hope it’s right
Determine What is the efficiency of a machine whose work output is 4 joules, and whose work input is 10 joules?
Answer:
The efficiency of the machine is 40 %.
Explanation:
We have,
Output work by the machine is 4 joules and the input work is 10 joules.
It is required to find the efficiency of a machine. The efficiency of a machine is given by the ratio of output work to the input work. It is given as :
[tex]\eta=\dfrac{4}{10}\times 100\\\\\eta=40\%[/tex]
So, the efficiency of the machine is 40 %.
