Answer:
Explanation:
On rubbing a glass rod with silk, the electrons from the glass rod get transferred to the silk. The silk now has an excess of electrons and so is negatively-charged. On the other hand, the glass rod is deficient in electrons and hence is positively-charged.
In the above case, the silk undergoes negative electrification.
Now, when the positively charged glass rod is touched on the disc of a negatively charged gold leaf electroscope, the electrons shifts towards rod, hence amount of charge on gold leaves decreases and the divergence between the gold leaves decreases as unlike charges attract each other.
Hence, the divergence decreases when a glass rod rubbed with silk is brought near the disc of negatively charged electroscope.
hope it helps pls mark me as brainliest
The energy change in an endothermic reaction is: A. Internal B. External C. Negative D. Positive
Answer:
Positive
Explanation:
In an endothermic reaction, the products are at a higher energy than the reactants. This means that the enthalpy change of the reaction (∆H) is positive
A man of mass 75kg stands on a weighing machine in a lift. Determine the reading of the weighing machine when the lift is moving: 1. Upwards with an acceleration of 2m/s² 2. Downwards with a constant velocity of 1.5m/s 3. Downwards with an acceleration of 2.5m/s²
Explanation:
Given that,
Mass of a man, m = 75 kg
(1) We need to find the reading of the weighing machine when the lift is moving upwards with an acceleration of 2 m/s². When the lift is moving upward, reading of the weighing machine is given by :
R = m(g+a)
R = 75 (9.8+2)
R = 885 N
(2) When the lift is moving downwards with a constant velocity of 1.5m/s. It means that the lift is at rest. So, the reading is :
R = mg
R = 75 (9.8)
R = 735 N
(3) When the lift is moving downwards with an acceleration of 2.5 m/s². In this case,
R = m(g-a)
R = 75 (9.8-2.5)
R = 547.5 N
Hence, this is the required solution.
A 2.00 m long string transmits
waves at 12.9 m/s. At what
frequency will it create standing
waves with 3 loops?
(Unit = Hz)
Answer:
The frequency at which the string will create a standing wave be with three loops is 8.6 Hz
Explanation:
The speed of the of the wave, v = 12.9 m/s
The number of loops of the standing wave = 3 loops
The length of the string = 2.00 m
Given that one loo = half of the wavelength, we have;
Three loops = 3 × half = One and half wavelength = 1.5·λ
The frequency of a wave = f = v/λ
Therefore, we have;
The frequency, f = 12.9/1.5 = 8.6 Hz
The frequency at which the string will create a standing wave be with three loops = 8.6 Hz.
Answer:
9.675
Explanation:
got it right on acellus
(02.10 LC)
Which American sport stems from a combination of the British sports rugby and soccer?
Baseball
Basketball
Tennis
Football
Question 2 Multiple Choice Worth 5 points)
Answer:
football
Explanation:
I took the 2.10 quiz and got it wrong so it must be football
If you look at faint stars, you can see them more easily on the edges of your vision than if you try to look directly at them. Why is this true?
Answer:
The retina comprises of rod and cone cells . The rod cells are responsible for black and white vision and require low light levels while the cone cells are responsible for color vision and require good/high light levels for better functioning.
When faint stars are looked at on the edges of the vision it allows more light from faint objects to strike the rod cells which then becomes more visible.
If the s – t graph of a particle is parallel to the t – axis, the speed of the particle is (a) zero (b) constant (c) infinite (d) non-uniform
Answer:
(b) constant
Explanation:
parallel to t - axis means, at all the times, the s component does not change, it remains same, i. e., the speed is constant.
:-)
Answer:
zero
Explanation:
if the velocity time graph is parallel to the time axis its mean body has not covered the path in other words body is at rest.So the velocity of the body should be zero
so the speed is zero
hope my answer will help u
A machine can never be 100% efficient because some work is always lost due to which factor? friction gravity static input force
Explanation:
Hi,
The answer is friction.
There is almost no machine which are not affected by friction. It losts some work due to friction while working.
Hope it helps..
Answer:
friction
Explanation:
the other options dont effect efficiency
(8.86 + 1.0 x 10^-3)÷3.610×10^-3
Answer:
2454.57
Explanation:
Step 1: Solve
[tex]\frac{(8.86+0.001)}{(3.610)(10^{-3}) }[/tex]
[tex]\frac{8.861}{0.003.61 }[/tex]
2454.57
Therefor the answer to this equation is 2454.57
plz help
I need it fast
Answer:
perpendicular to
Explanation:
it means perpendicular to .....should u come across something like this / / , this one means parallel to .....
Answer:
perpendicular
Explanation:
Some of the most popular symbols are:
Heart symbol: this represents love, compassion and health.
Dove symbol: this represents peace, love, and calm.
Raven symbol: this represents death and doom.
Tree symbol: this represents growth, nature, stability, and eternal life.
Owl symbol: this represents wisdom and intelligence.
Earth orbits 1 AU from the Sun, and the Oort cloud extends from about 10,000 to 100,000 AU from the Sun. If you represent Earth’s orbit around the Sun with a paper plate 4 inches in radius, how far away will the inner edge of the Oort Cloud be? The outer edge? Express your answers in miles.
Explanation:
Earth’s orbit around the Sun represented as :
1 AU = 4 inches
Therefore,
Inner edge of the Oort Cloud represented as :
10,000 AU = 40,000 / 63360 = 0.631 miles
Outer edge of the Oort Cloud represented as:
100,000 AU = 400,000 / 63360 = 6.31 miles
A box with mass of 2 kg is pushed directly horizontally over a horizontal surface (with friction) at a constant speed of 10 m/s. The force of the push is 60 N. How much thermal energy is generated pushing the box a distance of 15 m
Answer:
E= 600 W
Explanation:
Given that
m = 2 kg
Speed , v= 10 m/s
Force , F= 60 N
Given that box is moving with constant velocity, it means that friction force will be 60 N.
f = 60 N
Therefore total energy generated
E= f x v
E= 60 x 10 = 600 W
E= 600 W
Thus the answer will be 600 W.
Solve for angles A-D
Will mark as BRAINLIEST.... Plz answer the 44. Ques
Answer:
T= 2.66 seconds
Explanation:
Convert 80 km to m, which would be 0.08 m
[tex]t = d \div s[/tex]
[tex]t = 0.08 km\div 108kmph[/tex]
[tex]t = 0.00074074074 \: h[/tex]
[tex]1 \: hour = 3600 \: sec[/tex]
[tex] \frac{1}{3600} \times \frac{0.00074}{x} [/tex]
[tex]0.00074074074h \times 3600s = 2.66s[/tex]
A butterfly is flying around and its velocity(v) as a function of time(t) is given in the graph below where rightwards is the positive velocity direction. What is the butterfly's displacement x from t=2 to 4s? Answer with two significant digits.
Answer: 19 meters.
Explanation:
We want to find the total displacement between t = 2s and t = 4s.
To do it, we can integrate our function, first write our velocity equation.
for t ≤ 3s, we have a linear equation, let's write it:
A linear relationship can be written as:
y = a*t + b
where a is the slope and b is the y-axis intercept.
For a line that passes through the points (x1, y1) and (x2, y2), the slope can be written as:
a = (y2 - y1)/(x2 - x1).
Now we can see that our line passes through the points (1, 0) and (0, -2)
then the slope is:
a = (0 -(-2)/(1 - 0) = 2/1 = 2
and knowing that when t = 0s, v(0s) = -2m/s, then our equation is:
v(t) = (2m/s^2)*t - 2m/s for t ≤ 3s
now, for t ≥3s the equation is constant, v(t) = 4m/s.
then we have
v(t) = (2m/s^2)*t - 2m/s -------if t ≤ 3s
v(t) = 4m/s ----- if t ≥ 3s
Now we integrate over time to get the position:
for t ≤ 3s we have:
p(t) = (1/2)*(2m/s^2)*t^2 - 2m/s*t + C
where C is a constant of integration, as we are calculating the displacement this constant actually does not matter, so we can use C = 0m
p(t) = (1m/s^2)*t^2 - 2m/s*t for t ≤ 3s
and p(3s) = (1m/s^2)*3s^2 - 2m/s*3s = 9m - 6m = 3m is the initial position of the other part of the function.
for t ≥ 3s we have:
p(t) = 4m/s*t + p(3s) = 4m/s*t + 3m
then the position equation is:
p(t) = (1m/s^2)*t^2 - 2m/s*t ---- t ≤ 3s
p(t) = 4m/s*t + 3m --- if t ≥ 3s
Now the displacement will be:
p(4s) - p(2s) where for each time, you need to use the correct function:
p(4s) = 4m/s*4s + 3m = 16m + 3m = 19m
p(2s) = (1m/s^2)*2s^2 - 2m/s*2s = 4m - 4m = 0m
p(4s) - p(2s) = 19m - 0m = 19m
The butterfly displacement x from t=2 to 4s is 19 meters.
What is displacement?The spacing between two specified points is represented by the one-dimensional quantity of displacement (symbolised as d or s), commonly known as length or distance.
The total displacement between t = 2s and t = 4s.
Integrate our function, the velocity equation.
for t ≤ 3s, we have a linear equation, let's write it:
A linear relationship can be written as:
y = a x t + b
where a is the slope and b is the y-axis intercept.
For a line that passes through the points (x1, y1) and (x2, y2), the slope can be written as:
a = (y2 - y1)/(x2 - x1).
The line passes through the points (1, 0) and (0, -2)
The slope is:
a = (0 -(-2)/(1 - 0) = 2/1 = 2
When t = 0s, v(0s) = -2m/s, then our equation is:
v(t) = (2m/s²) x t - 2m/s for t ≤ 3s
now, for t ≥3s the equation is constant, v(t) = 4m/s.
v(t) = (2m/s²) x t - 2m/s -------if t ≤ 3s
v(t) = 4m/s ----- if t ≥ 3s
Now we integrate over time to get the position:
for t ≤ 3s we have:
p(t) = (1/2) x (2m/s²) x t^2 - 2m/s x t + C
where C is a constant of integration, to calculate the displacement this constant actually does not matter,
p(t) = (1m/s²)*t^2 - 2m/s x t for t ≤ 3s
and p(3s) = (1m/s^2) x 3s² - 2m/s x 3s = 9m - 6m = 3m is the initial position of the other part of the function.
for t ≥ 3s we have:
p(t) = 4m/s x t + p(3s) = 4m/s x t + 3m
then the position equation is:
p(t) = (1m/s^2) x t² - 2m/s x t ---- t ≤ 3s
p(t) = 4m/s x t + 3m --- if t ≥ 3s
Now the displacement will be:
p(4s) - p(2s) where for each time, you need to use the correct function:
p(4s) = 4m/s x 4s + 3m = 16m + 3m = 19m
p(2s) = (1m/s²) x 2s²- 2m/s x 2s = 4m - 4m = 0m
p(4s) - p(2s) = 19m - 0m = 19m
Thus, the displacement is 19 m.
To learn more about displacement, refer to the link:
https://brainly.com/question/11934397
#SPJ2
Identify the wood turning equipment and what it does.
А
is used to turn wood. It rotates and carves wood to produce a
form.
Answer:
lathe
perfectly symmetrical
Answer: A lathe is used to turn wood . It rotates and carves wood to produce a perfectly symmetrical form .
First one is lathe .
Second one is perfectly symmetrical .
Explanation: I just took the test on Plato and had 100%
A wave has a frequency of 5 Hz and a wavelength of 0.5 m, what is the speed of this wave?
Answer:
2.5 m/s
Explanation:
The speed of a wave can be found using the following formula.
v= λ * f
where λ is the wavelength in meters (m) and f is the frequency of the wave in Hertz (Hz).
We know the wavelength is 0.5 m and the frequency of the wave is 5 Hz.
Therefore,
λ= 0.5 m
f = 5 Hz
v= 0.5 * 5
Multiply 0.5 by 5, or divide 5 by 2.
0.5 * 5= 2.5 or 5/2=2.5
v= 2.5
Add appropriate units. The units for wave speed are m/s (meters per second).
v= 2.5 m/s
The speed of the wave is 2.5 meters per second.
A small cylinder is rolled along a ruler and completes two revolutions. The circumference is the distance around the outside of a circle. What is the circumference of the cylinder? A 4.4 cm B 5.2 cm C 8.8 cm D 10.2 cm
Answer; 4.4cm
Explanation: There is a ruler upon which the cylinder start from 1.4cm and reaches 10.2cm
distance traveled =10.2-1.4=8.8
since this cylinder is small so the linear distance can be approximately taked as rotational distance(as in case of point charge) so
2x2πxr =8.8
so the circumference will be 2πr=4.4cm
Guys, can you please answer these three questions. I'm having trouble doing them.
Answer:
17) a) 30 kg·m/s
b) 30 kg·m/s
c) 0.3 m/s.
18) 2.4 m/s
19) 360,000 N
The different make of car is safer because the force acting on it is 28,800 N, resulting much less impact
Explanation:
17) By conservation of linear momentum principle, we have;
m₁·v₁ + m₂·v₂ = m₁·v₁' + m₂·v₂'
Where;
m₁ = The mass of the astronaut = 100 kg
v₁ = The initial velocity of the astronaut = 0 m/s
m₂ = The mass of the equipment box = 2.5 kg
v₂ = The initial velocity of the equipment box = 0 m/s
v₁' = The final velocity of the astronaut
v₂' = The final velocity of the equipment box = 12 m/s
The final momentum of the equipment box = Mass of the equipment box × Final velocity
a) The final momentum of the equipment box = 2.5 kg × 12 m/s = 30 kg·m/s
b) Given that the box and the astronaut will move in opposite directions, we have;
m₁·0 + m₂·0 = -m₁·v₁' + m₂·v₂'
m₁·v₁' = m₂·v₂'
Therefore, the momentum of the astronaut will be equal to the momentum of the equipment box = 30 kg·m/s
c) The velocity of the astronaut is given by th following relation;
100×0 + 2.5×0 = -100×v₁' + 2.5×12
100×v₁' = 2.5×12
v₁' = 2.5×12/100 = 30/100 = 0.3 m/s
The final velocity of the astronaut = 0.3 m/s.
18) By conservation of linear momentum principle, we have;
m₁·v₁ + m₂·v₂ = m₁·v₁' + m₂·v₂'
Where;
m₁ = The mass of the railway truck= 4000 kg
v₁ = The initial velocity of the railway truck= 8 m/s
m₂ = The mass of the stationary truck = 6000 kg
v₂ = The initial velocity of the stationary truck = 0 m/s
v₁' = The velocity of the two trucks immediately after collision
Therefore, we have;
4000 kg × 6 m/s + 6000 × 0 = (6000 + 4000) × v₁' = 10,000·v₁'
24,000 kg·m/s = 10,000·v₁'
v₁' = 24,000/10,000 = 2.4 m/s
The velocity of the two trucks immediately after collision is = 2.4 m/s
19) The change in kinetic energy of the car due to the collision = 1/2·m·(v₂² - v₁²)
The initial velocity of the car, v₁ = 12 m/s
The final velocity, v₂ = 0 m/s
The mass of the car, m= 600 kg
The time in which the car is brought to rest = 2 seconds
Initial time at point of collision, t₁ = 0 s
Time after collision, t₂ = 0.02 s
By Newton's second law of motion, we have
The force F acting on the car = Rate of change in momentum produced by the force
F = m × dv/dt
Force = m × (v₂ - v₁)/(t₂ - t₁) = 600×(0-12)/(0.02 - 0) = -360,000 kg·m/s²
The force acting on the car is equal and opposite to the force of the car = 360,000 N
b) For the different make of the car, we have;
m × (v₂ - v₁)/(t₂ - t₁) = 600×(0-12)/(0.25 - 0) = -28,800 kg·m/s². = -28,800 N
Therefore, the different make of car is safer because the force acting on it is 28,800 N, resulting much less impact.
The motion of a particle along a straight line is described by the equation x=6+4t2 -t 4 , where x is in meter and t is in seconds. Find position, velocity, and acceleration of the object when t=2s.
Answer:
The position of the particle is 6m
The velocity of the particle is 16 m/s in negative direction
The acceleration of the object is -40 m/s²
Explanation:
Given;
motion of the particle along a straight line as x = 6 + 4t² - t⁴
The position of the object when t = 2s
x = 6 + 4(2)² - (2)⁴
x = 6 + 16 - 16
x = 6m
The velocity of the object when t = 2s
Velocity = dx/dt
dx/dt = 8t - 4t³
when t = 2s
Velocity = 8(2) - 4(2)³
Velocity = 16 - 32
Velocity = -16m/s
Velocity = 16 m/s (in negative direction)
The acceleration of the object when t = 2s
Acceleration = d²x/dt² = 8 - 12t²
Acceleration = 8 - 12 (2)²
Acceleration = -40 m/s²
a ferris wheel has a centripetal acceleration equal to 2m/s squared. what is the centripetal force acting on a 45 kg boy riding in one of the cars when the car is on the top of the ferris wheel? what is the force exerted by the seat on the boy when the car is at the top of the ferris wheel
Explanation:
[tex]centripetal \: force = \frac{m {v}^{2} }{r} [/tex]
Centripetal force = 45 * 2 = 90 N
Therefore, centripetal force acting on a 45 kg boy riding in one of the cars when the car is on the top of the ferris wheel is 90 N.
The force exerted by the seat on the boy when the car is at the top of the ferris wheel is a centrifugal (pseudo force) acting (since the since the seat is in non- inertial frame) in exact opposite direction (Outwards) as the centripetal force and is equal in magnitude.
Answer answer answer it it it
Answer:
(B) Parachutes
Explanation:
Air resistance works to slow down trains and airplanes, so it isn't desirable. Air resistance also causes pendulums to slow and stop.
Parachutes need air resistance to slow a person's fall. So air resistance is desirable here.
Answer:
B i answered it it it
Explanation:
A car is moving on straight highway with a speed of 108 km/h.
Answer:
5.3333 sec
Explanation:
initial speed: u = 108km/hr or 30 m/s
final speed: v = 0m/s
distance travelled: s = 80m
time the car took to stop: = t sec
[tex]v^{2} - u^{2}[/tex] = 2as,
a = ([tex]v^{2} - u^{2}[/tex])/2s
a = (0-900)/160
a = -5.625 [tex]ms^{-2}[/tex]
v = u + at,
t = (v - u)/a
t= (0 - 30)/(-5.625)
t = 5.3333 sec
If a gas and a liquid are both at the same temperature, the particles of gas have a higher average kinetic energy. True or false?
Answer:
True
Explanation:
The average kinetic energy is the measure of how freely the molecules of a substance moves relative to the other molecules within the substance. Gas and liquids are together termed fluids, but the molecules of a gas naturally has more more average kinetic energy that that of a liquid, if they are kept at the same temperature. This explains why gases are easy to expand, and have to be confined by a container. So the particles of a gas has more kinetic energy that that of a liquid even if they are kept at the same temperature.
[tex]r=s^2/t^2[/tex] 1. If s is tripled and t stays constant, r is multiplied by... 2. If t is doubled, and s stays constant, r is multiplies by...
Answer:
9 and 4
Explanation:
The relation is:
● r = s^2 / t^2
Triplind s means multiplying it by 3. Since it's an equation we should multiply both sides by the same number
Let k be the number we should multiply by r
●k* r = (3s)^2 / t^2
●k* r = 9s^2 /t^2
We have multiplied s^2 by 9 so we should do the same for r.
k = 9
■■■■■■■■■■■■■■■■■■■■■■■■■■
Doubling t means multiplying it by 2.
Let x be the number we shoukd multiply by r.
● x* r = s^2/(2t)^2
● x*r = s^2/ 4t^2
We have multiplied t^2 by 4 so we should do the same for r.
x= 4
Se suelta un cuerpo desde la azotea de un edificio de 180m de alto. Luego de 3s se lanza verticalmente hacia abajo otro cuerpo. Si ambos llegan simultáneamente al piso, calcular la rapidez con la que fue lanzado el segundo cuerpo (g=10m/s2).
Answer:CcCcccccc
Explanation:
Rfsgqh
Which is
easier
Push
or pull.
when force is at angle
Answer:
pull
Explanation:
because when you push there is one component of force that adds to tge weight of body and hence there is more friction. Whwn you pull the vertical component of force is against the weight of body and hence friction is low.
How much work is done in moving a body of mass 1.0 kg from an elevation of 2 m to
an elevation of
Answer:
The work done is -176.4 J.
Explanation:
Given that,
Mass = 1.0 kg
An elevation of 2 m to an elevation of 20 m.
Suppose, Find the work done by the gravitational field of the earth?
We need to calculate the force
Using formula of force
[tex]F=mg[/tex]
Put the value into the formula
[tex]F=1.0\times9.8[/tex]
[tex]F=9.8\ N[/tex]
We need to calculate the displacement
Using formula of displacement
[tex]Displacement = s_{2}-s_{1}[/tex]
[tex]s=20-2=18\ m[/tex]
The direction of displacement is upward.
Since gravitational force is downwards and displacement is upwards,
Then the angle is 180°.
We need to calculate the work done
Using formula of work
[tex]W=f\cdos s\cos\theta[/tex]
[tex]W=9.8\times18\cos180[/tex]
[tex]W=-176.4\ J[/tex]
Hence, The work done is -176.4 J.
How to find average acceleration only using displacement and time?
Answer:
Average acceleration = Displacement / (time)^2
Explanation:
The unit for acceleration is
[tex]m {s}^{ - 2} [/tex]
Displacement = m
Time = s
Hence the units of displacement and time should be manipulated to get the unit of acceleration.
You can't. You can only find average velocity.
But if you also know that initial velocity is zero ... the object started from rest ... then
Avg acceleration =
2 x displacement / time-squared
Use the diagram to answer each question.
Why might a researcher further classify the data in the chimpanzee dier table to include separate information of males and females ?
Answer:
In the data table, we can see the frequency distribution in the diet of a given type of chimpanzee.
Why a researcher further classify the data separating information of males and females?
Well, the objective of the researcher is to find information about these chimpanzees, so if he notices that the diet varies (even slightly) between males and females, separating the information between males and females would be useful to know how the diet varies, and why this happens.
This is the primary motive of why a researcher would want to separate the information of males and females.
what is space in detail?
Answer:
Space in the astronomy and cosmology space is 3 dimensional region and earth atmosphere end is called space.
Explanation:
Space is the everything of the top earth atmosphere moon, starts, milky way, black hole and GPS satellites an distant,space also called between stars,moon,planet.
Space is all the extends far in all directions, space is finite unbound space surface of the earth has finite are no beginning or not end.
Space contains there are three dimensions is called 3 D space,an space is to refer an interval during signal transmitted also used by the character, bytes, words and octets in digital signal.
space is that term can refer to various in science, communications and mathematics,and maintain orbits for responsible time, space is usually to begin at the lowest attitude satellites can maintain orbits.
space coordinates are uniquely define the location of any particular point and that continuum requires more than coordinates,and the number of dimensions and conventional space or digital communications during the signal represents logic is 0 words in a digital signal.
