Answer:
Explanation:
This is a torque problem where balance is achieved when the sum of the torques equal 0. The equation for torque is
[tex]\tau=F*r[/tex] where F is the force in Newtons that is perpendicular to the lever arm, and r is the length of the lever arm in meters.
450(2) = 350r and
[tex]\frac{450(2)}{350}=r[/tex] so
r = 2.6 m
86,400 seconds into day
Answer:
60×60×24=86,400
Explanation:
i.e. 86,400 secs is 1 day
1 hour = 60 minutes
1 minute = 60 seconds
1 day = 24 hours
60 min. × 60 sec. × 24 hr.
60 × 60 × 24 = 86,400 seconds
∴ 86,400 seconds = 1 day
A large atomic bomb produces around 8.00x1015J of energy. How much matter does that bomb turn into energy?
A)2.67x10^79kg
B)2.67x10^7kg
C)7.20x10^32kg
D)0.0889kg
Answer:
D)0.0889kg
Explanation:
If a large atomic bomb produces around 8.00x10¹⁵J of energy, then from Einstein's energy law i.e E=mc² we can calculate that the amount of matter is 0.0889kg. The correct option is D.
What is Einstein's energy law?
The Einstein Energy Law, often referred to as Einstein's famous equation relates the energy of a particle (E) to its mass (m) and the speed of light (c). The equation is as follows:
E = mc²
This equation shows that energy (E) and mass (m) are equivalent and interchangeable and that a small amount of mass can be converted into a large amount of energy. This is the basis for understanding nuclear reactions and the energy released in processes like nuclear fusion and fission.
Here in the question,
To calculate the mass that is converted into energy in an 8.00x10¹⁵J nuclear reaction, we can rearrange the equation to solve for m:
m = E / c²
where c = 3 x 10⁸ m/s is the speed of light in a vacuum.
Substituting the values, we get:
m = 8.00x10¹⁵ J / (3 x 10⁸ m/s)²
m = 0.0889kg
Therefore, a large atomic bomb that produces around 8.00x10¹⁵ J of energy converts approximately 0.0889kg of matter into energy. This is a very small amount of matter, but because c² is such a large number, a huge amount of energy can be released from a small amount of matter in a nuclear reaction.
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Indoor pollution experts conducted an analysis of the paint used in many office buildings which revealed that the paint contains traces of lead. The lead seems to rise to the surface of the paint and escape into the building's air supply. Tests show that because of the chemical drying process, the lead is not discernible on the surface until the paint has been on the walls for at least six months. To meet safety standards, owners should repaint walls at least every six months, or cover the walls with a different material.Which of the following, if true, would most weaken the conclusion above?A) The indoor pollution experts had no clear understanding of why it took six months for the lead to become discernible on the paint's surface.B) The indoor pollution experts neglected to examine the paint for traces of other toxic substances such as cadmium and mercury.C) The amount of lead found on the surface of the paint after six months remained constant for the next two years.D) The indoor pollution experts found that even in those offices painted with a different brand of paint, traces of lead were still found in the air workers breathed.E) The indoor pollution experts' research shows that the amounts of lead that come into contact with the air people breathe, even in the office buildings that used the greatest amount of paint, are too low to affect workers.
Answer:
E) The indoor pollution experts' research shows that the amounts of lead that come into contact with the air people breathe, even in the office buildings that used the greatest amount of paint, are too low to affect workers
Explanation:
The conclusion that would weaken the above statement if true was that the amount of lead found in air was not hazardous for the people living in building and the effects of such paint was quite low o affect workers.which two phenomena make up electromagnetism?
A) moving charges in an electric current attract each other
B) permanent magnets form a magnetic field from one pole to the other pole
C) an electric current causes a magnetic field around a core of magnetic metal
D) a moving magnet causes an electric current in a magnetic metal
Explanation:
the correct answer is option ( C ) and ( D )
(9x10^2) + (1x10^2)
10x10^4
10x10^3
1x10^4
1x10^3
Answer:
10 x 10⁴
I hope it's helps you
Answer:
Yes
Explanation:
A 210 Ohm resistor uses 9.28 W of power. How much current flows through the resistor? (unit=A)
Answer:
.21
Explanation:
i see everyone got it wrong so ill give you the answer, good luck :)
D 2. Which of the following is an example of a specific goal?
O I want to lose weight.
I want to get stronger.
O I want to be able to walk one mile in 15 minutes.
I want to improve my speed.
I want to improve my speed
Answer:
D
Explanation:
Question 7 of 25
Which two chemical equations are balanced?
O A. 2PBrg + 3Cl2 - 2PC13 + 3Br2
O B. 2Na+ MgCl2
2NaCl + Mg
-
C. 2LIOH + 2H2S - Li2S + 2H20
D. 2AgNO3 + NaCl - NaNO3 + 2AGCI
Answer:
2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂
2Na + MgCl₂ → 2NaCl + Mg
Explanation:
A balanced chemical equation is a chemical equation that have an equal number of elements of each type on both sides of the equation
Among the given chemical reactions, we have;
2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂
In the above reaction;
The number of phosphorus, P, on either side of the equation = 2
The number of bromine atoms, Br, on either side of the equation = 6
The number of chlorine atoms, Cl, on either side of the equation = 6
Therefore, the number of elements in the reactant side and products side of the reaction are equal and the reaction is balanced
The second balanced chemical reaction is 2Na + MgCl₂ → 2NaCl + Mg
In the above reaction, there are two sodium atoms, Na, one magnesium atom and two chlorine atoms on both sides of the reaction, therefore, the reaction is balanced
A simple machine has efficiency 90%. What does it mean? No machine has 109 efficiency,why?
Answer:
Efficiency of a machine is 90% this means that the total energy produced to the machine only 90% is useful and given as a output.
Machines are not 100% efficient because some of the work done by a machine is used to overcome friction
can ya pls answer dis!
Answer:
Here Is An OverView of What I Know About Science:
To understand what science is, just look around you. What do you see? Perhaps, your hand on the mouse, a computer screen, papers, ballpoint pens, the family cat, the sun shining through the window …. Science is, in one sense, our knowledge of all that — all the stuff that is in the universe: from the tiniest subatomic particles in a single atom of the metal in your computer's circuits, to the nuclear reactions that formed the immense ball of gas that is our sun, to the complex chemical interactions and electrical fluctuations within your own body that allow you to read and understand these words. But just as importantly, science is also a reliable process by which we learn about all that stuff in the universe. However, science is different from many other ways of learning because of the way it is done. Science relies on testing ideas with evidence gathered from the natural world. This website will help you learn more about science as a process of learning about the natural world and access the parts of science that affect your life.
Explanation:
Science helps satisfy the natural curiosity with which we are all born: why is the sky blue, how did the leopard get its spots, what is a solar eclipse? With science, we can answer such questions without resorting to magical explanations. And science can lead to technological advances, as well as helping us learn about enormously important and useful topics, such as our health, the environment, and natural hazards. Without science, the modern world would not be modern at all, and we still have much to learn. Millions of scientists all over the world are working to solve different parts of the puzzle of how the universe works, peering into its nooks and crannies, deploying their microscopes, telescopes, and other tools to unravel its secrets. I Hope This Helps.
1. Una carga Q1 = + 12 μC se coloca a una distancia r = 0.024 m desde una carga Q2 = + 16 μC. a) Determina la magnitud de la fuerza electrostática que actúa sobre las dos cargas, Q1 y Q2. b) ¿Es la fuerza la atracción o repulsión? 2. Determina la intensidad del campo eléctrico a una distancia radial de r = 48 mm desde una carga de Q = 24 μC. 3. Una carga Q1 = 24 mC se coloca a una distancia r = 0.032 m desde una carga Q2 = - 12 μC. a. Determina la cantidad de energía potencial eléctrica que tiene la carga Q1. b. Determina el potencial eléctrico en la posición de Q2.
Answer:
1. a. 3,000 N
b. Repulsión
2. 46.875 × 10⁶ N/C
3. a. 81,000 J
b. 6.75 × 10⁹ V
Explanation:
1. Los parámetros dados son;
Q₁ = +12 μC, Q₂ = +16 μC
La distancia entre las cargas, r = 0.024
La magnitud de la fuerza electrostática, F, entre cargas se da como sigue;
[tex]F = k \times \dfrac{Q_1 \cdot Q_2}{r^2}[/tex]
Donde, k = constante de Coulomb = 9.0 × 10⁹ N · m² / C²
Por lo tanto, obtenemos;
F = 9.0 × 10⁹ × 12 × 10⁻⁶ × 16 × 10⁻⁶ / 0.024² = 3.000
La magnitud de la fuerza electrostática, entre las cargas, F = 3000 N
(b) Dado que tanto Q₁ como Q₂ son cargas positivas, y las cargas iguales se repelen entre sí, la fuerza es la repulsión.
2) La intensidad de un campo eléctrico, E, se da como sigue;
[tex]E = \dfrac{k \cdot Q}{r^2}[/tex]
La magnitud de la carga, Q = 24 μC
La distancia donde se mide el campo, r = 48 mm = 0.048 m
Por lo tanto, E = 9.0 × 10⁹ × 12 × 10⁻⁶ / 0.048² = 46,875,000 N / C
La intensidad de un campo eléctrico, E = 46,875,000 N / C = 46.875 × 10⁶ N / C
3. La magnitud de las cargas son;
Q₁ = 24 mC
Q₂ = -12 μC
La distancia entre las cargas, r = 0.032 m
un. El potencial eléctrico de una carga, [tex]U_E[/tex] , se da de la siguiente manera;
[tex]U_E = k \times \dfrac{Q_1 \cdot Q_2}{r}[/tex]
Por lo tanto;
[tex]U_E[/tex] = 9.0×10⁹ × 24 × 10⁻³ × (-12) × 10⁻⁶ /0.032 = -81,000
La energía potencial eléctrica entre la carga, Q₁ y Q₂= -81,000 J
b. El potencial eléctrico de Q₁ en Q₂, V₁ = [tex]k \times \dfrac{Q_1 }{r}[/tex]
Por lo tanto, V₁ = 9.0×10⁹ × 24 × 10⁻³/0.032 = 6.75 × 10⁹
El potencial eléctrico de Q₁ en Q₂, V₁ = 6.75 × 10⁹ V
Assuming Faraday constant to be 96500c/mol and relative atomic mass of copper 63,calculate the mass of copper liberated by 2A current in 5min.ans 0.196gm
Answer: The mass of copper liberated is 0.196 g.
Explanation:
The oxidation half-reaction of copper follows:
[tex]Cu\rightarrow Cu^{2+}+2e^-[/tex]
Calculating the theoretical mass deposited by using Faraday's law, which is:
[tex]m=\frac{M\times I\times t(s)}{n\times F}[/tex] ......(1)
where,
m = actual mass deposited = ? g
M = molar mass of metal = 63 g/mol
I = average current = 2 A
t = time period in seconds = 5 min = 300 s (Conversion factor: 1 min = 60 sec)
n = number of electrons exchanged = 2
F = Faraday's constant = 96500 C/mol
Putting values in equation 1, we get:
[tex]m=\frac{63 g/mol\times 2A\times 300s}{2\times 96500 C/mol}\\\\m=0.196g[/tex]
Hence, the mass of copper liberated is 0.196 g.
A man sees a deer in the road and slams on his brakes. If he is traveling at 45.2 m/s and comes to a stop in 2.74 s, what is his acceleration? O -6:02 m/s2 -0.0606 m/s2 -47.9 m/s2 0 -16.5 m/s2
Answer:
16.50 m/s²
Explanation:
initial velocity(u)=45.2 m/s
final velocity(v)= 0 (it stops)
time taken(t)= 2.74 s
now,we have
acceleration(a)= (v-u)/t
= (0-45.2 m/s)/2.74s
= -45.2 m/s / 2.74s
= -16.50 m/s²
Answer:
[tex]\boxed {\boxed {\sf -16.5 \ m/s^2}}[/tex]
Explanation:
We are asked to find the acceleration of a man driving. Acceleration is the change in velocity over the change in time. Acceleration is calculated with the following formula.
[tex]a= \frac{v_f- v_i}{t}[/tex]
The driver's initial velocity is 45.2 meters per second. His final velocity is 0 meters per second because he came to a stop. He stopped in 2.74 seconds.
[tex]\bullet \ v_f= 0 \ m/s \\\bullet \ v_i= 45.2 \ m/s \\\bullet \ t= 2.74 \ s[/tex]
Substitute these values into the formula.
[tex]a= \frac{0 \ m/s - 45.2 \ m/s }{ 2.74 \ s}[/tex]
Solve the numerator by subtracting.
[tex]a= \frac{- 45.2 \ m/s }{ 2.74 \ s}[/tex]
[tex]a= -16.49635036 \ m/s^2[/tex]
The original measurements of velocity and time have 3 significant figures, so our answer must have the same. For the number we calculated, that is the tenths place. The 9 in the hundredth place tells us to round the 4 in the tenths place up to a 5.
[tex]a \approx -16.5 \ m/s^2[/tex]
The acceleration is approximately -16.5 meters per second squared. The acceleration is negative because the man slowed down and came to a stop.
A skipper on a boat notices wave crests passing his anchor chain every 5.6 s . He estimates the distance between wave crests to be 16 m . He also correctly estimates the speed of the waves. Find this speed.
Answer:
v = 2.85 m/s
Explanation:
Given that,
A skipper on a boat notices wave crests passing his anchor chain every 5.6 s.
The distance between wave crests to be 16 m.
We need to find the speed of the waves. The speed of a wave can be calculated by the formula as follows :
[tex]v=f\lambda\\\\v=\dfrac{\lambda}{T}\\\\v=\dfrac{16}{5.6}\\\\v=2.85\ m/s[/tex]
So, the speed of the wave is 2.85 m/s.
factor that affect gravitation
1) Two major factors, mass and distance, affect the strength of gravitational force on an object.
2) Most common factors that affect gravity are mass of the body, distance from centers, shape of bodies,etc. Gravity is a binding force, always acting to bind any material closure and closure inwards. If we think this way, then gravity is maximum at its centre and decreases slowly away from its centre.
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have a nice day
Ploughing field with harrow pulled by a tractor is a modern technology
Ploughing field with harrow pulled by a tractor being a modern technology is true.
What is Technology?This involves the use of scientific knowledge to tackle different life problems and has different sectors.
Ploughing field with harrow pulled by a tractor involves machines and not manual labour which makes it a modern technology.
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A ball is dropped from the roof of a 25-m-tall building. What is the velocity of the object when it touches the ground? Suppose the ball is a perfect golf ball and it bounces such that the ve locity as it leaves the ground has the same magnitude but the op posite direction as the velocity with which it reached the ground How high will the ball bounce? Now suppose instead that the ball bounces back to a height of 20 m. What was the velocity with which it left the ground?
Answer:
a) [tex]h=25m[/tex]
b) [tex]v=19.8m/sec[/tex]
Explanation:
From the question we are told that:
Height [tex]h=25m[/tex]
Bounce Height [tex]h'=20m[/tex]
Generally the Kinematic equation is mathematically given by
[tex]V=\sqrt{2gh}\\\\V=\sqrt{2*9.81*25}[/tex]
[tex]V=22.1m/sec[/tex]
Therefore Height
[tex]h=\frac{V^2}{2g}\\\\h=\frac{22.1^2}{2*9.81}[/tex]
[tex]h=25m[/tex]
b)
Generally the Kinematic equation is mathematically given by
[tex]v^2=2ah[/tex]
[tex]v^2=2*9.8*20[/tex]
[tex]v=\sqrt{2*9.8*20}[/tex]
[tex]v=19.8m/sec[/tex]
why does apparent depth of different liquids vary
.............................
Clois what is the weight of a body in the earth, if its weig is 5Nin moon?
Explanation:
because the moon has less mass than earth, the force due to gravity at the lunar surface is only about 1/6 that on earthso,the weight of a body on earth is 6×5N =30N
Given: F = k· m. g
Solve for "k"
Answer:
[tex]F = kmg \\ k = \frac{F}{mg} [/tex]
Explanation:
F = k . m . g
=> F = k . mg
[tex] = > k = \frac{F}{mg} (ans)[/tex]
Difference between gravitational force and frictional
Explanation:
gravitational force or gravity is the force of attraction between objects that have mass.
frictional force is the forec that opposes motion (movement) when two surface are in contact. (acts in the opposite direction of motion)
so to sum it up,
- gravtional force is the force of attraction between objects that have mass.
- objects on the earth have weight because of gravitational force between them and the earth.
frictional force
- oppose motion
- slow down and stop moving objects and;
- produce heat
hope it helps :)
A jet plane is launched from a catapult on an aircraft carrier. In 2.0 s it reaches a speed of 42 m/s at the end of the catapult. Assuming the acceleration is constant, how far did it travel during those 2.0 s?
First find Acceleration
Initial velocity=u=0m/sFinal velocity=v=42m/sTime=t=2sDistance=sAcceleration=a[tex]\boxed{\sf Acceleration=\dfrac{v-u}{t}}[/tex]
[tex]\\ \sf\longmapsto Acceleration=\dfrac{42-0}{2}[/tex]
[tex]\\ \sf\longmapsto Acceleration=\dfrac{42}{2}[/tex]
[tex]\\ \sf\longmapsto Acceleration=21m/s^2[/tex]
Using second equation of kinematics
[tex]\boxed{\sf s=ut+\dfrac{1}{2}at^2}[/tex]
[tex]\\ \sf\longmapsto s=0(2)+\dfrac{1}{2}(21)(2)^2[/tex]
[tex]\\ \sf\longmapsto s=21(2)[/tex]
[tex]\\ \sf\longmapsto s=42m[/tex]
State one effect of increase in heat for a temperature range of 50°C to 100°C
on Plastic
Answer:
why is fraction called a necessary evil
The heat for a temperature in plastic increases at the range of 50°C to 100°C then the plastic decreases its stiffness or flexural modulus.
It is given that the temperature is increased from 50°C to 100°C that means temperature is increasing.
It is required to state the effect of increase in heat on plastic.
What will be the effect of increase in heat for a temperature range of 50°C to 100°C on Plastic?The plastic starts to lose its stiffness or we say that it converts into a softened material as long as we increase the temperature of the material.
So if we increase the temperature too much or exceed above the limit of temperature range then it will distort.
Also there are many qualities that can be affected by increasing the temperature like mechanical property, material fatigue or chemical phenomenon.
Therefore, the heat for a temperature range of 50°C to 100°C
Plastic increases then the plastic decreases its stiffness or flexural modulus.
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What is the centripetal acceleration of a point on the perimeter of a bicycle wheel diameter 70.0 cm when the bike is moving 8.0 m/s? (160 m/s)
It’s 180 m/s^2 dude. I think I have you in my class lol.
The centripetal acceleration of an object is due to the changing velocity in a circular path and the centripetal acceleration of the bicycle is 182.85 m/s².
What is Centripetal acceleration?Centripetal acceleration of an object can be defined as the property of the motion of an object which is traversing a circular path. Any object which is moving in a circular path and has an acceleration vector pointed towards the center of that circular path is known as Centripetal acceleration.
The centripetal acceleration of an object can be calculated by the formula:
ac = v²/ r
where, ac = centripetal acceleration,
v = velocity of the object,
r = radius of the circular path
The centripetal acceleration of the object will be:
ac = (8)²/ r
radius = diameter/ 2
radius = 70/ 2
radius = 35cm or 0.35 m
ac = 64/ 0.35
ac = 182.85 m/s²
Therefore, the centripetal acceleration of the bicycle will be 182.85 m/s².
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How does a fuse work?
A. A material burns out when current is excessive
B. A material burns out when resistance is excessive
C. A material burns out when voltage is excessive
D. A material acts as a switch to prevent electricity from flowing when voltage is excessive
Answer:
A. a material burns out when current is excessive
The density of a material in CGS system of units is 4g cm-³. In a system of units in which unit of length is 10 cm and unit of mass is 100g, the value of density of material will be...?
1) 0.04
2) 40
3) 0.4
4) 400
[tex]\sf\underline{Solution:}[/tex]
Here , the density of the material is 4g cm³ but it is not given in CGS system.
$\sf{As\:we\:know\:that:}$
$\sf\bold{Density=}$ $\sf\dfrac{Mass}{Volume}$
$\space$
[tex]\sf{Now,according \: to \:the\:question:}[/tex]
$\sf\small{Density\:of\:the\:material=4}$ $\sf\dfrac{g}{cm^2}$
$\space$
$\sf{It\:is\:given\:that:}$
In the system of units the mass is 100gram.
$\space$
Hence,
$\sf{The\:mass\:unit\:for\:4g=}$ $\sf\dfrac{4}{100}$ $\sf{units}$
$\space$
In the system of units,the length is 10cm.
Henceforth,
$\sf\small{The\:length \:for\:1cm\:units=}$ $\sf\dfrac{1}{10}$ $\sf{units}$
$\space$
☆ Substitute the required values in the given formula-
$\sf\purple{Density=}$ $\sf\dfrac\purple{Mass}\purple{volume}$
$\space$
$\sf\underline\bold{Density\:of\:the\:material:}$
= $\sf\dfrac{4/100}{1/10^3}$ $\sf\bold{units}$
$\space$
= $\sf\dfrac{4/100}{1/1000}$ $\sf\bold{units}$
$\space$
= $\sf\dfrac{4000}{100}$ $\sf\bold{units}$
$\space$
$\sf\underline\bold\blue{=40\:units}$
$\sf\small{Therefore,option\:2nd\:is\:correct!}$
_______________________________
In a lunar experiment, a 950-g aluminum (920 J/(°Ckg)) sphere is dropped from the space probe while is 75 m above the Lunar ground. If the sphere’s temperature increased by 0.11°C when it hits the ground, what percentage of the initial mechanical energy was absorbed as thermal energy by the aluminum sphere?
Answer:
13.759 % of the initial mechanical energy is lost as thermal energy.
Explanation:
By the First Law of Thermodynamics we know that increase in internal energy of the object ([tex]U[/tex]), in joules, is equal to the lost amount of the change in gravitational potential energy ([tex]U_{g}[/tex]), in joules:
[tex]\frac{x}{100} \cdot \Delta U_{g} = \Delta U[/tex] (1)
Where [tex]x[/tex] is the percentage of the energy loss, no unit.
By definition of the gravitational potential energy and internal energy, we expand this equation:
[tex]\frac{x\cdot m \cdot g \cdot h}{100} = m\cdot c\cdot \Delta T[/tex] (1b)
Where:
[tex]m[/tex] - Mass of the object, in kilograms.
[tex]g[/tex] - Gravitational acceleration, in meters per square second.
[tex]h[/tex] - Initial height of the object above the lunar ground, in meters.
[tex]c[/tex] - Specific heat of aluminium, in joules per degree Celsius-kilogram.
[tex]\Delta T[/tex] - Temperature increase due to collision, in degree Celsius.
If we know that [tex]m = 0.95\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], [tex]h = 75\,m[/tex], [tex]c = 920\,\frac{J}{kg\cdot ^{\circ}C}[/tex] and [tex]\Delta T = 0.11\,^{\circ}C[/tex], then the percentage of energy loss due to collision is:
[tex]x = \frac{100\cdot c\cdot \Delta T}{g\cdot h}[/tex]
[tex]x = \frac{100\cdot \left(920\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (0.11\,^{\circ}C)}{\left(9.807\,\frac{m}{s^{2}} \right)\cdot (75\,m)}[/tex]
[tex]x = 13.759\,\%[/tex]
13.759 % of the initial mechanical energy is lost as thermal energy.
define Archemedics principle?
THIS IS YOUR ANSWER :
Archimedes’ principle, physical law of buoyancy, discovered by the ancient Greek mathematician and inventor Archimedes, stating that any body completely or partially submerged in a fluid (gas or liquid) at rest is acted upon by an upward, or buoyant, force, the magnitude of which is equal to the weight of the fluid displaced by the body.
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Tick (3) the correct statement about electrostatic charges.
(a) Earthing causes positive charges to flow from the object to the ground.
(b) Similar types of electric charges attract one another.
(c) An electroscope is used to determine the presence of electrostatic charges.
Answer:
similar type of electric charges attract one another
I think this is a coorect staement
Answer:
C ) An electroscope is used to determine the presence of electrostatic charges
