Answers
Related Questions
7. Apply Concepts: suppose the dog walked at a constant speed the whole way. What
would the graph look like then? Explain.
Answers
If the dog walked at a constant speed the whole way, the graph of the dog's position versus time would be a straight line. This is because the dog's velocity (which is the derivative of position with respect to time) would be constant, and the acceleration (which is the derivative of velocity with respect to time) would be zero.
What is the speed about?A straight line on a position-time graph indicates that the object is moving at a constant velocity. The slope of the line would be equal to the velocity of the dog.
If the graph is a horizontal line, it would indicate that the dog is at rest. If the line slopes upward, the dog is moving in the positive direction (for example, to the right in a position-time graph), and if the line slopes downward, the dog is moving in the negative direction.
In all, A constant speed means a constant velocity and the line is a straight line with a particular slope.
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A 1250kg car is stopped at a traffic light. A 3550kg truck moving at 8.33 m/s hits the car from behind. If the bumpers lock, how fast will the two vehicles move?
Answers
The final speed of the cars after the collision is determined as 6.16 m/s.
Final speed of the cars after collisionThe final speed of the cars after the collision is calculated from the principle of conservation of linear momentum as shown bellow.
m1v1 + m2v2 = v(m1 + m2)
where;
v1 is the initial velocity of the 1250 kg carv2 is the initial velocity of the 3550 kg carm1 is mass of 1250 kg carm2 is mass of 3550 kg carv is the final velocity of the two cars after collision
Substitute the given parameters and solve for "v".
1250(0) + 3550(8.33) = v(1250 + 3550)
29,571.5 = 4800v
v = 29571.5/4800
v = 6.16 m/s
Thus, the final speed of the cars after the collision is determined as 6.16 m/s.
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Which of the following is TRUE regarding Softball?
Softball is played with a smaller ball than baseball
Softball is played on a larger field than baseball
There are two popular forms of softball, distinguished by the type of pitch
Softball is the number two team participant sport in the United States
Answers
Answer:
There are two popular forms of softball, distinguished by the type of pitch.
Explanation:
Softball refers to a kind of sports that is similar to baseball in terms of game play but softball is played with a larger ball. The game of softball was first introduced as an indoor game in Chicago, Illinois, United States of America in the year 1887. Also, the field for playing softball is relatively smaller than that of baseball and as such its game play is quite faster.
Some of the kits and paraphernalia used for playing softball are base, bat, softball, gloves, jerseys etc.
There are two (2) main types of softball game and these are;
I. Fast-pitch softball.
II. Slow-pitch softball.
Hence, the true statement regarding softball is that, there are two popular forms of softball, distinguished by the type of pitch.
Answer:
the 3rd statement
Explanation:
softball ball is HUUUGE (like 11’ and baseballs are 9” if im correct) and the field isn’t bigger than a baseball field. the olympic field for baseball was 90m and softball was 60m! also softball is not 2nd. and the types of pitches are fast pitch and slow pitch!! i hope this helps
Calculate the ratio of H+ ions to OH– ions at a pH = 8. Find the concentration of H+ ions to OH– ions listed in Table B of your Student Guide. Then divide the H+ concentration by the OH– concentration. Record this calculated ratio in Table A of your Student Guide. Compare your approximated and calculated ratios of H+ ions to OH– ions at a pH = 8. Are they the same? Why or why not? Record your explanation in Table A. What is the concentration of H+ ions at a pH = 8? mol/L What is the concentration of OH– ions at a pH = 8? mol/L What is the ratio of H+ ions to OH– ions at a pH = 8? :1 OR 1:
Answers
At pH = 8, the ratio of H+ ions to OH- ions is 1:1, indicating a neutral solution. The concentration of H+ ions and OH- ions is approximately 1 x 10^(-8) mol/L. The calculated and approximated ratios should match.
To calculate the ratio of H+ ions to OH- ions at pH = 8, we need to use the relationship between pH and the concentration of H+ ions. The pH scale is a logarithmic scale that measures the acidity or alkalinity of a solution based on the concentration of H+ ions.
The formula to calculate the concentration of H+ ions (\(C_H\)+) from pH is:
\(C_H\)+ = \(10^(^-^p^H^)\)
Substituting pH = 8 into the formula:
\(C_H\)+ = \(10^(^-^8^))\)
Using the properties of logarithms, we can calculate the concentration of H+ ions:
\(C_H\)+ ≈ 1 x \(10^(^-^8^))\) mol/L
According to the concept of neutrality in water, the concentration of H+ ions is equal to the concentration of OH- ions. Therefore, the concentration of OH- ions (\(C_O_H\)-) is also approximately 1 x \(10^(^-^8^))\)mol/L.
To calculate the ratio of H+ ions to OH- ions, we divide the concentration of H+ ions by the concentration of OH- ions:
Ratio = \(C_H\)+ / \(C_O_H\)-
Ratio = (1 x \(10^(^-^8^))\) / (1 x \(10^(^-^8^))\))
Ratio = 1:1
The ratio of H+ ions to OH- ions at pH = 8 is 1:1, indicating a neutral solution. This means that the concentration of H+ ions is equal to the concentration of OH- ions, resulting in a balanced ratio.
When comparing the calculated ratio of 1:1 to the approximated ratio at pH = 8, they should be the same because the ratio of H+ ions to OH- ions is determined solely by the pH value, which is consistent and mathematically derived. Therefore, the approximated and calculated ratios should match.
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the concentration of water vapor in the atmosphere known as
Answers
Earth’s gravitational field is 7.51 N/kg at the altitude of the space shuttle. What is the size of the force of attraction between a student of mass 53 kg and Earth? Answer in units of N.
Answers
Explanation:
395.53 N
The force of attraction between a student of mass 53 kg and Earth is calculated using the equation F = G*m1*m2/r^2, where G is the gravitational constant (7.51 N/kg), m1 is the mass of the student (53 kg), m2 is the mass of Earth, and r is the distance between them (the altitude of the space shuttle). Plugging in these values, we get F = 7.51*53*5.97e24/((6.37e6 + 6.37e6)^2) = 395.53 N.
How can you determine the number of neutrons in an atom?
A. Mass number plus number of electrons
B. Atomic number minus mass number
C. Mass number minus atomic number
D. Atomic number plus mass number
Answers
Answer:
B. Atomic number minus mass number
Explanation:
A car accelerates from 20 m/s to 30m/s in 10s
,draw velocity time graph to show cars motion.find the distance its travels by calculating the area under the graphing?
Answers
Answer:
250 m
Explanation:
Refer to the attachment for the graph. Here, we are asked to calculate the distance travelled.
⇒ Area under the graph = Distance travelled by the body
Let the distance travelled by the body be S. Area under the graph will be the area of the trapezium ABCD.Area of trapezium = ½ × Sum of parallel sides × Height
\( \twoheadrightarrow \quad \sf {S = \dfrac{1}{2}\times (AD + BC) \times OC} \\ \)
\( \twoheadrightarrow \quad \sf {S = \dfrac{1}{\cancel{2}}\times (10+30) \times \cancel{10}} \\ \)
\( \twoheadrightarrow \quad \sf {S = 1\times 50 \times 5} \\ \)
\(\twoheadrightarrow \quad \boxed{\red{\sf{ S = 250 \; m}}}\\\)
❝ Therefore, distance travelled by the body is 250 m. ❞
In terms of electric pressure, describe a charged capacitor.
Answers
Answer: The capacitor is fully charged when the voltage of the power supply is equal to that at the capacitor terminals. This is called capacitor charging; and the charging phase is over when current stops flowing through the electrical circuit.
12
The motion of an object can be described by it
A.
speed.
В.
position.
C.
direction.
D.
all of these
Answers
Answer:
D
Explanation:
The motion of an object can be described by its speed, position, and direction so its all of the above
What is the minimum amount ( in kg) of liquid water at 26 degrees that would be required to completely melt 41 grams of ice? The specific heat capacity of liquid water is 4180 J/kg/°C and the specific heat of fusion of ice is 3.33×105 J/kg.
Answers
Approximately 0.123 kg of liquid water at 26 degrees Celsius would be needed to melt 41 grams of ice.
To calculate the minimum amount of liquid water required to melt 41 grams of ice at 0°C, we need to consider the energy required for the phase change from solid to liquid, which is known as the specific heat of fusion of ice.
The energy required to melt 1 kg of ice is 3.33×105 J/kg.
Therefore, the energy required to melt 41 grams of ice is (3.33×105 J/kg) × (41/1000) kg = 13653 J.
To calculate the amount of liquid water required, we use the specific heat capacity of water, which is 4180 J/kg/°C.
Assuming the initial temperature of water is 26°C, the amount of water needed can be calculated as (13653 J) ÷ (4180 J/kg/°C) ÷ (26°C) = 0.123 kg or approximately 123 ml of water.
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1. On a force vs. mass graph, what would be the slope of the line?
2. On a Free Body Diagram, if the forces are all balanced, what do you know about the
object? Can it be moving?
Answers
1. By Newton's second law,
F = m a
so the slope of the line would represent the mass of the object.
2. If all the forces are balanced, then the object is in equilibrium with zero net force, which in turn means the object is not accelerating. So the object is either motionless or moving at a constant speed.
Mary pushed a box across the floor with 54N to the left and Doug helped her by exerting a force
of 75N to the left and another force of 20N was exerted on the box in the opposite direction,
what is the net force acting on the box? *
Help plzz
Answers
a heater has a power of 2500W. The heater is turned on for 180 seconds. Calculate the energy transferred by the heater
Answers
The energy transferred by the heater that has a power of 2500W and is turned on for 180s is 450,000J.
How to calculate energy?Electrical energy is the energy made available for consumption or consumed in the form of electricity or electric power.
Electrical energy can be calculated as follows:
Electrical energy = Power x Time.
The total amount of electrical energy used depends on the total power used by all electrical devices and the total time they are used in the home.
According to this question, a heater has a power of 2500W and is turned on for 180 seconds. The energy can be calculated as follows;
E = 2500W × 180s
E = 450,000J
Therefore, 450,000J is the energy transferred to the heater.
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When using the lens equation, a negative value as the solution for di indicates that the image is
Answers
Answer:
The Anatomy of a Lens
Refraction by Lenses
Image Formation Revisited
Converging Lenses - Ray Diagrams
Converging Lenses - Object-Image Relations
Diverging Lenses - Ray Diagrams
Diverging Lenses - Object-Image Relations
The Mathematics of Lenses
Ray diagrams can be used to determine the image location, size, orientation and type of image formed of objects when placed at a given location in front of a lens. The use of these diagrams was demonstrated earlier in Lesson 5 for both converging and diverging lenses. Ray diagrams provide useful information about object-image relationships, yet fail to provide the information in a quantitative form. While a ray diagram may help one determine the approximate location and size of the image, it will not provide numerical information about image distance and image size. To obtain this type of numerical information, it is necessary to use the Lens Equation and the Magnification Equation. The lens equation expresses the quantitative relationship between the object distance (do), the image distance (di), and the focal length (f)
I was hoping you could help me with this question?
Answers
In order to determine the angle between the given vectors, use the following formula:
\(\vec{u}\cdot\vec{v}=uv\cos \theta\)where the left hand side of the equation is the dot product of u and v vectors, u and v are the magnitude of the vectors and θ is the angle between the vectors.
Then, by solving for θ, you obtain:
\(\begin{gathered} \cos \theta=\frac{\vec{u}\cdot\vec{v}}{uv} \\ \theta=\cos ^{-1}(\frac{\vec{u}\cdot\vec{v}}{uv}) \end{gathered}\)Then, first calculate the dot product:
\(\begin{gathered} \vec{u}\cdot\vec{v}=(u_x)(v_x)+(u_y)(v_y) \\ \vec{u}\cdot\vec{v}=(0)(11)+(-10)(-12)=120 \end{gathered}\)The magnitudes of the vectors are:
\(\begin{gathered} u=\sqrt[]{u^2_x+u^2_y}=\sqrt[]{(0)^{}+(-10)^2}=\sqrt[]{100}=10.00 \\ v=\sqrt[]{v^2_x+v^2_y}=\sqrt[]{(11)^2+(-12)^2}=\sqrt[]{265}\approx16.28 \end{gathered}\)Then, by replacing the dot product and the valued of u and v into the expression for θ, you obtain:
\(\theta=\cos ^{-1}(\frac{120}{10.00\cdot16.28})\approx42.51\)Hence, the angle between u and v vectors is approximately 42.51 degrees.
A transverse wave on a string has an amplitude of 20 cm, a wavelength of 35 cm, and a frequency of 2.0 Hz. The wave moves in the positive x-direction.
--Enter any fractional coefficients as fractions, i.e., do not approximate fractions using decimals. Enter as itself; do not multiply it with other numerical factors. Enter phase angles in inverse function form if they do not evaluate one of the special angles on the unit circle.
--Write the mathematical description of the displacement y1(x,t) from equilibrium for the wave if, at t=0, x=0, and y1=0.
y1(x,t)= ___m
--Write the mathematical description of the displacement y2(x,t) from equilibrium for the wave if, at t=0, x=0, and y2=20 cm.
y2(x,t)= ___m
Write the mathematical description of the displacement y3(x,t) from equilibrium for the wave if, at t=0, x=0, and y3=−20 cm.
y3(x,t)= ___m
Write the mathematical description of the displacement y4(x,t) from equilibrium for the wave if, at t=0, x=0, and y4=13 cm.
y4(x,t)= ___m
Answers
(a) The mathematical description of the displacement of the wave, y1(x,t) = 0.2 m.
(b) The mathematical description of the displacement of the wave, y2(x,t) = 0.4 m.
(c) The mathematical description of the displacement of the wave, y3(x,t) = 0.2 m
(d) The mathematical description of the displacement of the wave, y4(x,t) = 0.33 m
Wave functionThe general wave function is written as follows;
y(x, t) = Acos(kx - ωt)
where;
k is the wave number = 2π/λA is amplitude of the wave = 20 cmω is angular speedλ is the wave length = 35 cmy0 = Acos(kx - ωt)
y0 = 20cm x cos(0 - 0)
y0 = 20 cm
From equilibrium of the wave, at t=0, x=0, y1 = 0y1(x,t) = 20cm x cos(0 - 0) = 20 cm
y1(x,t)= 20 cm = 0.2 m
Thus, y1 = y1 + y0
From equilibrium of the wave, at t=0, x=0, y2 = 20 cmy2 = y0 + y1 + y2
y2 = 20 cm + 0 + 20 cm
y2(x,t)= 40 cm = 0.4 m
From equilibrium of the wave, at t=0, x=0, y3 = -20 cmy3 = y0 + y1 + y2 + y3
y3 = 20 cm + 0 + 20 cm - 20cm
y3(x,t)= 20 cm = 0.2 m
From equilibrium of the wave, at t=0, x=0, y4 = 13 cmy4 = y0 + y1 + y2 + y3
y4 = 20 cm + 0 + 20 cm -20 cm + 13 cm
y4 = 33 cm
y4(x,t) = 33 cm = 0.33 m
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1. A ball is at rest on the top of a hill (see the figure).
At the top of the hill, the ball will have [the maximum value of its, no, the minimum value of its] gravitational potential energy and [no, the maximum value of its] kinetic energy. If the ball rolls down the hill then, its [gravitational potential energy, kinetic energy] is converted to [gravitational potential energy, kinetic energy] when it gets to the ground.
2. Get your stopwatch ready and prepare to drop the object from the height h you selected in the previous step. You should drop the object so its [bottom, top, middle] part is initially at the height h. The initial speed of the ball [zero, 9.8 m/s, 9.8 m/s^2, depends on the height h] You'll need to measure the time from when the ball leaves your hand to exactly when it hits the ground [ for the first time it bounces, after it bounces and then comes to rest, both the first time and then after it bounces; then average the two times]
.
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2. When dropping the object, you should drop it so its top part is initially at the height h. The initial speed of the ball will be zero since it starts from rest. To measure the time it takes for the ball to hit the ground, you should start the stopwatch when the ball leaves your hand and stop it when the ball hits the ground for the first time. It is recommended to perform multiple trials and calculate the average time to minimize errors.
A motorcycle, travelling cast, starts from rest, moves in a straight line with a constant acceleration and covers a distance of 64 m in 4 s.Calculate a) Its acceleration b) Its final velocity c) At what time the motorcycle had covered half the total distance d) What distance the motorcycle had covered in half the total time.
Answers
The motorcycle had covered a distance of 16 meters in half the total time.
a) To calculate the acceleration, we can use the formula:
a = (v - u) / t
where a is the acceleration, v is the final velocity, u is the initial velocity (which is 0 since the motorcycle starts from rest), and t is the time.
Given:
u = 0 m/s (initial velocity)
v = ? (final velocity)
t = 4 s (time)
s = 64 m (distance)
Using the equation of motion:
s = ut + 1/2at^2
We can rearrange the equation to solve for acceleration:
a = 2s / t^2
a = 2(64) / (4)^2
a = 128 / 16
a = 8 m/s^2
Therefore, the acceleration of the motorcycle is 8 m/s^2.
b) To find the final velocity, we can use the formula:
v = u + at
v = 0 + (8)(4)
v = 32 m/s
Therefore, the final velocity of the motorcycle is 32 m/s.
c) To determine the time at which the motorcycle had covered half the total distance, we divide the total distance by 2 and use the formula:
s = ut + 1/2at^2
32 = 0 + 1/2(8)t^2
16 = 4t^2
t^2 = 4
t = 2 s
Therefore, the motorcycle had covered half the total distance at 2 seconds.
d) To calculate the distance covered in half the total time, we use the formula:
s = ut + 1/2at^2
s = 0 + 1/2(8)(2)^2
s = 0 + 1/2(8)(4)
s = 0 + 16
s = 16 m
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A 0.20 mass on a horizontal spring is pulled back a certain distance and released. The maximum speed of the mass is measured to be 0.20 . If, instead, a 0.40 mass were used in this same experiment, choose the correct value for the maximum speed.
a. 0.40 m/s.
b. 0.20 m/s.
c. 0.28 m/s.
d. 0.14 m/s.
e. 0.10 m/s.
Answers
Answer:
d
Explanation:
Ya gon find the Kenitic Energy first
K=½mv²===> K=½×0.2×(0.2)²===> 0.1(0.04)===> 0.004
and now the replacement:
0.004=½×0.4V²====> v²=0.02===> V=0.14m/s
To pull a nail out of a wood board a carpenter does 1000 J of work. The hammer he uses does 835 J of work. What is the efficiency of the hammer?
Answers
Answer:
83.5%
Explanation:
A. Organized process to test a hypothesis
B. An educated guess about the solution to a problem
C. Observations & measurements recorded
D. A summary based on the results of an experiment
E. The response that is measured in an experiment
F. The factor that is manipulated during an experiment
Answers
The scientific method include Observations >> Data; Factor manipulated >> Independent Variable, process to test >> experiment, guess >> hypothesis, results >> Conclusion and response >> dependent variable.
What is an observation in science?Observation is the first step of the scientific method, which then requires to raise a question that will be answered by a testable hypothesis.
The scientific method is a series of well-established steps used to collect scientific empirical data/evidence, which allow to test a given hypothesis.
In conclusion, the scientific method include Observations >> Data; Factor manipulated >> Independent Variable, process to test >> experiment, guess >> hypothesis, results >> Conclusion and response >> dependent variable..
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Which is one feature of tropical wet-dry climates that tropical wet climates do not have?
savannas
rainforests
year-round rain
no change of seasons
Answer : A Savannas
Answers
Answer:
a
Explanation:
blocks a and b have masses m and 2m , respectively. the blocks are connected using a light string and an ideal pulley in the atwood machine shown. when the blocks are released from rest, block b accelerates downward with acceleration a . block b is replaced with a block that has twice the mass. the blocks are again released from rest. which of the following is a correct expression for the new acceleration of the blocks?
Answers
The following is a correct expression for the new acceleration of the blocks a/4 .
What is acceleration?Acceleration is the rate of change of an object's velocity. It is described as the change in the velocity of an object over time. Acceleration can be positive, negative, or zero. When the velocity of an object increases, it is said to have a positive acceleration. When the velocity of an object decreases, it is said to have a negative acceleration. When the velocity of an object remains the same, it has a zero acceleration. Acceleration can be calculated by dividing the change in velocity of an object by the time it took for the change to occur. Acceleration also has direction, meaning that it can be in the direction of the velocity or in the opposite direction of the velocity.
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A BODY OF MASS 1 KG HAS WEIGHT 10 N A CERTAIN PLACE . WHAT IS WEIGHT OF 5 KG. PLZ TELL ME IN EXPLAINATION . TROUBLE. I WILL GIVE BRAINLIEST BUT NO LINK
Answers
Answer:
50 N
Explanation:
Given that,
A body has a mass of 1 kg that weight 10 N at a certain place. We need to find the weight of 5 kg.
1 kg = 10 N
To find weight of 5 kg, use unitary method such that,
5 kg = (5×10) N
= 50 N
Hence, the required weight is equal to 50 N.
Match each term with the appropriate definition
Answers
Answer:
opaque = 4
malleable = 3
ductile = 2
lustrous (or whatever the bottom word is) = 1
Explanation:
I need answers help please
Answers
Answer: Can't see clearly.
Explanation:
from watching the video, approximate the total time it took for kevin to cross his lawn on the zip line. if kevin has an initial velocity of 3 m/s and comes to a stop at the end of the zip line, calculate the distance he traveled.
Answers
The relationship between speed, distance, and time is described using the formula speed distance time. An object traveling 10 miles in 5 minutes averages 120 miles per hour.
What is speed divided by distance?10 miles were covered in total.
It took five minutes in total.
The formula can be used to determine the speed.
s = d/t
s being the speed
D stands for distance.
The amount of time used
Let's change the known variables in the equation above to get
s = 10/5
= 2 miles/minute
However, we must convert the speed to miles per hour in order to use it.
s=2 x 60 miles per hour
120 miles per hour.
An object traveling 10 miles in 5 minutes averages 120 miles per hour.
Consequently, the typical speed is 120 miles per hour.
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The figure above shows Case 1 of an experiment, in which the following events occur.
At time t1
, block A slides to the right along a horizontal surface toward identical block B, which is at rest.
At time t2
, block A collides elastically with block B and block A comes to rest.
At time t3
, the right side of block B reaches an ideal, horizontal spring with negligible mass and spring constant k1
. The spring is initially at its relaxed (uncompressed) length and fixed to a wall.
At time t4
, the spring is compressed a maximum distance d1
and block B is instantaneously at rest.
Assume there is negligible friction between each block and the surface. For parts (a)-(d), consider the system consisting of block A, block B, and the spring.
(a) Indicate whether the linear momentum of the two-block–spring system is either constant or not constant during the time interval from t1
to immediately before t3
, and explain why.
Answers
Over the time period from t₁ to just before t₃, the two-block-spring system is linear momentum does not change because there are no external forces acting on the system to change its momentum.
Explain why the linear momentum of the two-block–spring system is either constant or not during the time period between t₁ and the time just before t₃?
The linear momentum of the two-block-spring system remains constant from t₁ until just before t₃.
Prior to the collision at time t₂, block A has a momentum to the right that is Pa = ma ×va, whereas block B has a momentum that is Pb = 0 because it is at rest. Because there is no external force acting on the system, its overall momentum is conserved.
All out Ptotal = Dad + Pb = mama × va
Expect there is immaterial erosion between each block and the surface. Take into consideration the spring, block A, and the system for parts (a) to (d).
Following the collision at time t₂, block B experiences a velocity of vb to the right and comes to a stop. Because the collision is elastic, all of the system's kinetic energy is conserved, but momentum is still conserved:
The two-block system is moving to the right at a constant velocity vb from time t₂ to just before time t₃, so the momentum of the system is constant. Ptotal = ma₀ plus mbvb plus mb ×vb
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PLEASE HELP
Which is not an accurate statement about Earth's gravitational pull?
A) Earth's gravitational pull helps keep it in orbit.
B) Earth's gravitational pull is the same as Jupiter's gravitational pull.
C) Earth's gravitational pull is 9.8 m/s2.
D) Earth's gravity helps keep people from floating outside of the planet.