-- When you see the words "uniform speed", that means the car's speed is not changing.
-- Right under those words in the picture, there's a note to remind you that "uniform speed" also means "acceleration is zero".
-- The whole key to this question is to find out if you remember that acceleration and net force always go together.
.==> If there's net force, then there's acceleration.
.==> If there's acceleration, then there's net force.
.==> If there's NO net force then there's NO acceleration.
.==> If there's no acceleration, then there's no net force.
-- In this picture, there's no acceleration, so there's no net force.
-- The driving force on the car is 2000N forward.
-- But the car's speed is not changing, so the net force on the car must be zero.
-- So that 'resisting' force pulling the car backwards must be 2000N. Then the net force on the car adds up to zero.
-- If the resisting force pulling the car backwards is not zero, then the net force on the car would not be zero, and the car's speed would be changing.
Which figure represents the electric field lines of two negative point charges?
Help
Answer:
The question is incomplete because the options are not given. We'll solve this question with the options.
There are two properties of negative charges which we have to consider to find the figure of its electrical field.
Firstly, for a negative charge, the electrical field lines are always directed radially outwards and they don't intersect.
Secondly, we know that similar charges repel each other, so there will be no electrical field present directly between these two negative charges. Electrical field line will be present between two charges only when there is a force of attraction.
Taking both of these facts into consideration, the electrical field line between two negatives is represented by the figure below.
Answer:
Figure C
Explanation:
Got it correct on Edmentum
what type of circuit is shown?
A. open parallel circuit
B. open series circuit
C. closed parallel circuit
D. closed series circuit
Answer:
A. open parallel circuit im pretty sure
Explanation:
Answer:
D
Explanation:
The bulbs are on the same wire as the battery, so its series. Current is flowing so its closed.
A negative slope on the velocity vs. time graph indicates that the object is not
accelerating
A. True
B. False
Answer: False, I think
Explanation:
Well it depends. Its hard to say without a function of the graph. Given a velocity graph, the first derivative is the acceleration.
Negative slope on a velocity graph means you are going in the negative direction. And over time, your velocity per unit of time is also decreasing. That means we are accelerating in the negative direction
Why is it a good idea to explore the health and fitness field in terms of career
options?
O A. There are career opportunities that require a variety of skills and
talents.
O B. It's a growing field.
O c. Many options in this field allow you to help other people through
your job.
D. All of the above.
Answer: I think the answer is option D.
if the distance from the source is doubled, what will happen to sound intensity
Answer: sound intensity will decrease to the one - fourth of its initial value.
Explanation:
The relationship between sound intensity and the distance obeys inverse square law, where the intensity of sound is inversely proportional to the square of the distance. That is,
I = 1/ r^2
Where
I = sound intensity
r = distance.
If the distance from the source is doubled, sound intensity will decrease in value to the one - fourth of its initial value.
A squirrel jumps down from a tall tree. Assuming the squirrel is in free fall,
how far will it have fallen in 1.3 seconds?
O A. 6.4 m
B. 13.2 m
O C. 8.3 m
O D. 11.1 m
Answer:
8.3 m
Explanation:
Which statement best explains acceleration?
O A.
It is the total distance covered over a period of time.
B.
It is a change in velocity over a period of time.
Oc.
It is a change in displacement over a period of time.
OD.
It is a change in direction over a period of time.
Answer:
It is a change in velocity over a period of time.
Explanation:
It is measured in metres/second2 using an accelerometer.Please help me find the last one ASAP! Thanks :))) (You don't have to send the definition)
2) Light reflects off of surfaces. It is also absorbed by opaque materials
and transmitted through transparent objects. Consider this diagram of
tvo sheets of construction paper. Elaborate on the behavior of the
incident light waves
A)
White paper reflects the incoming waves, while black
absorbs the incoming waves.
White paper reflects some of the incoming waves,
while black absorbs all of the incoming waves.
B)
Q
The white paper absorbs and transmits light waves,
while the black paper absorbs all light waves.
Some of the light waves incident on the white paper
D) are reflected and some are absorbed. None of the
Light waves are reflected from the black paper.
Answer: B
White paper reflects some of the incoming waves,
while black absorbs all of the incoming waves.
Explanation:
Light is reflected off of white surfaces. Light is absorbed by opaque materials and transmitted through transparent objects.
In the case of a white paper, a white paper can be considered as a translucent material in which some of the light incident on it bounces off while some pass through it. Therefore, we can conclude that White paper reflects some of the incoming waves,
while black absorbs all of the incoming waves.
The part of a circult that increases the electric potential of the electrons is the
Answer:
The part of a circuit that increases the electric potential of the electrons is the battery.
Answer:
Explanation:it is an electromotive force that increases the potential of the electrons.
Which of the following is the best description of the term resultant
displacement?
A. The scalar that joins all the points along the path.
B. The average of all the displacement vectors.
C. The total distance traveled.
O D. The shortest distance from the beginning point to the end point.
Answer:
D
Explanation:
Displacement refers to the shortest, or straight-line path from one point to another. It is a vector, thus A is incorrect. It is not the average, but rather the sum of all displacement vectors, so B is incorrect. It is not the distance traveled, as some paths have longer distances than others, while leading to the same destination, hence same displacement. (i.e. running around in circles yields positive distance traveled but zero displacement.)
Answer:
Explanation: D
Displacement is a vector. It has direction and it has magnitude. But we are asked for the resultant displacement. You have to use pythagorean theorem. This makes our answer always positive. That essentially means distance, since you did just do the distance formula.
A is wrong because that tells you perimeter
B is wrong because that tells you the midpoint
C is wrong because displacement and distance are two different things. We dont want the distance of the two vectors
D is correct, this perfectly explains the distance formula
During every chemical reaction what happens
A ball is thrown upward with ten units of momentum initially. What is the “recoil” momentum of the earth? Why do we not feel this?
Answer:
1.) Momentum = 10 units
2.) Because of gravity
Explanation:
According to the Newton 3rd law of motion, we realise that in collision, momentum is always conserved.
So, if a ball is thrown upward with ten units of momentum initially, the “recoil” momentum of the earth will be approximately 10 units of momentum. We do not feel this because of the gravity.
A planet has a period of revolution about the Sun equal to Tand a mean distance from the Sun equal to R. T varies directly as _____.
A. R
B. R²
C. R3
D. R4
E. R5
Answer:
C. R3
Explanation:
Answer:
C. R3
Explanation:
Plato
Resistance is a measure of.
a) the energy per unit charge in a circuit
b) how hard it is for electrons to move through the circuit
c) how hard it is for electrons to move through the battery
d) the number of charge carriers in a circuit
static electricty is the study of..
A buildup of charge
B electric discharges
C electric fields
D all of the above
Answer:
all of the above
Explanation:
i study this kind of stuff in school
In charging by rubbing, electrons move from one material to another because
A. substances with very few neutrons have a net positive charge, so
they get the extra electrons.
O B. heavier substances get rid of electrons so they don't weigh as
much.
O C. the substance with the most protons steals electrons from the
other substance.
O D. some substances hold onto electrons tighter than other
substances, so they get the extra electrons.
Answer: D.
some substances hold onto electrons tighter than other
substances, so they get the extra electrons.
Explanation: When two substances are in contact by rubbing each other, there will be friction between them. The friction will stimulate what we called - Thermal energy. And what thermal energy does is the disrupt the bonding force or enhance it.
We can therefore conclude that some substances hold onto electrons tighter than other substances, so they get the extra electrons. Because at neutral state of the substance, the number of protons is equal to the number of electrons.
Different types of waves travel at different speeds. For example, sound waves travel more slowly than light waves. Have you ever been in a big empty room, or in a cave, and heard an echo? Echos happen because sound waves take time to travel to the wall and bounce back to your ears. But light is different. Light is much faster than sound. Light is the fastest moving thing in the universe. Because light waves and sound waves travel at different speeds, you can figure out how far you are from a storm by watching for lightning and listening for thunder. Lightning and thunder are actually the same thing! Thunder is just the sound that lightning makes. Because light is so quick, you see the lightning flash first. The sound travels more slowly, so you hear the thunder after. Thunder and lightning represent two kinds of waves: sound and light.
How do lightning and thunder illustrate the relationship between light and sound waves?
A Light moves faster than sound, so you hear thunder after you see lightning.
B Sound moves faster than light, so you see lightning after you hear thunder.
C Lightning and thunder are the same, so light and sound waves move together at the same time.
D Sound moves light, so when you hear thunder you know lightning will move toward you.
Answer:
A). Light moves faster than sound, so you hear thunder after you see lightning.
Explanation:
The lightning and thunder demonstrate that 'light travels faster than sound' which clearly portrays the relationship between the light and the soundwaves. When we see lightning in the sky before hearing the sound of thunder as the speed of light much higher than the speed of sound. Sound travels ~ 343 m/s or 1235 km/hr while light travels 300000 km/s. This difference in speed prevents us from considering lightning and thunder as the same thing. The 'sound is a pressure wave and therefore, takes time to travel and bounce back to our ears.' Thus, we happen to witness lightning first. Hence, option A is the correct answer.
why does a bouncing ball have a greater change in momentum than a ball that is just caught
If the ball bounces, then there is an additional velocity change sending the ball back upwards opposite the original direction. Thus, for the same collision time, bouncing involves a greater velocity change, a greater momentum change, and therefore a greater impulse.
Answer:
because with the change in momentum the velocity goes to zero. (more info below)
Explanation:
Momentum is the velocity change multiplied by the mass. When you think about it, bouncing an object means it comes back from anything it bounced against, giving it a velocity that is negative. This means that the velocity change for bouncing is greater than for colliding, as the velocity goes to zero in an inelastic collision like the one described.
hope this helped!
On which of the following objects, all sitting on the ground together, does
Earth exert a greater gravitational pull than a pencil? Check all that apply.
A. A basketball
B. A toothpick
C. A truck
D. A piece of paper
E. Your hand
Explanation:
a toothpick
Two vectors which do not lie along the same line represent what kind of
motion?
A. Resultant motion
B. Scalar motion
C. One-dimensional motion
D. Two-dimensional motion
How does the velocity change with time in uniform rectilinear motion of an object?
A ball rolls with a speed of 4.0 m/s across a level table that is 1.0 m above the floor. Upon reaching the edge of the table, it
follows a parabolic path to the floor. How many meters along the floor is the landing spot from the table?
Answer: 1.81m
Explanation:
Given the following:
Horizontal speed = 4m/s
Height of table = 1m
Taking the vertical component of the motion:
Using:
S = ut + 0.5 at^2
Where, S = height of table, a = acceleration due to gravity (9.8m/s^2), t = time and u = Initial Velocity in vertical direction = 0
1 = 0(t) + 0.5(9.8)t^2
1 = 4.9t^2
t^2 = 1 / 4.9
t^2 = 0.204081
t = sqrt(0.204081)
t = 0.452s
For Horizontal :
Gravitational acceleration is absent, therefore distance can be calculated using:
Distance = Velocity × time
Distance = 4m/s × 0.452s
Distance = 1.808 m
Distance = 1.81m
Describe the relationship between frequency and wavelength
Answer:
Frequency and wavelength are inversely related.
Explanation:
Frequency and wavelength have an inverse relationship because if one thing goes up another goes down. For example, if frequency goes up, the wavelength goes down and vice versa.
Answer:
The relationship between wavelength and frequency is that the frequency of a wave multiplied by its wavelength gives the speed of the wave.
Explanation:
Frequency and wavelength are related terms also, used to describe electromagnetic radiation or light. One simple equation is used to convert between them: frequency x wavelength = speed of light. λ v = c, when λ is wavelength, v is frequency, and c is the speed of light.
I know I'm really late but I hope this helps lol
HELP PLEASE!! A yellow ball with a mass of 2kg is rolling across the floor at 3m/s. A red ball with a mass of 3kg is rolling across the same floor at 3m/s. Which ball has greater kinetic energy, and why?
Answer: B. The red ball has greater kinetic energy, because it has a greater mass.
Explanation:
The factors influencing the kinetic energy of an object are its mass and its velocity. Both of the balls have the same velocity; however, the red ball has a greater mass. Therefore,
The red ball has greater kinetic energy, because it has a greater mass.
I hope this helps:)
An electron in a mercury atom drops from energy level f to energy level c by emitting a photon having an energy of
1. 8.20eV
2. 5.52eV
3. 2.84eV
4. 2.68eV
Answer:
The answer is 2.84 eV
Explanation:
An electron in a mercury atom drops from energy level f to energy level c by emitting a photon having an energy of 2.84eV.
What is mercury?Mercury is known to be a type of naturally-occurring chemical element that has been discovered in rock that is found in the earth's crust.
They can be found as a form of deposits of coal. On the periodic table, it symbol is "Hg" and it has about 80 atoms. It can be found as Elemental (metallic) mercury, Inorganic mercury compounds, etc.
Learn more about mercury atom from
https://brainly.com/question/964897
If you see ##### in a cell, you should
make the row taller
retype the number
type in a different number
make the column wider
Answer:
it's D. Make the column wider
Explanation:
Give a specific example of a vector quantity. Explain why this type of quantity would be used to describe this event.
Answer:
Vector Quantities Increase/Decrease in Temperature - The measurement of the medium's temperature is a scalar quantity; the measurement of the increase or decrease in the medium's temperature is a vector quantity. Velocity - The measurement of the rate at which an object changes position is a vector quantity.
Explanation:
Answer: velocity has a magnitude and a direction. This quantity is useful in every day lives in many ways. for example when you are driving in a car, its good to know the velocity in which the car is going.
Explanation: sorry its late
What is the photoelectric effect?
A the absorption of particles by a metal surface that is exposed to red light or infrared rays
B the proportional relationship between a photon's energy and the frequency of light.
C the emission of electrons from a metal caused by light striking the metal
D the ability of specialized photons to bounce off a metal surface.
Answer: C
the emission of electrons from a metal caused by light striking the metal
Explanation:
Photo means anything related to light in Physics and science generally.
Photoelectric effect explains the effect of light incident on metal surfaces by knocking out electrons on the metal surfaces.
The correct option is C
the emission of electrons from a metal caused by light striking the metal
9. A ball is thrown straight up with an initial speed of 30 m/s. How long will it take to reach the top of its trajectory, and high will the ball go?
Answer:
1.) Time t = 3.1 seconds
2.) Height h = 46 metres
Explanation:
given that the initial velocity U = 30 m/s
At the top of the trajectory, the final velocity V = 0
Using first equation of motion
V = U - gt
g is negative 9.81m/^2 as the object is going against the gravity.
Substitute all the parameters into the formula
0 = 30 - 9.81t
9.81t = 30
Make t the subject of formula
t = 30/9.81
t = 3.058 seconds
t = 3.1 seconds approximately
Therefore, it will take 3.1 seconds to reach to reach the top of its trajectory.
2.) The height it will go can be calculated by using second equation of motion
h = ut - 1/2gt^2
Substitutes U, g and t into the formula
h = 30(3.1) - 1/2 × 9.8 × 3.1^2
h = 93 - 47.089
h = 45.911 m
It will go 46 metres approximately high.