The correct option that determines gravitational pull is mass. Gravitational force is calculated using the masses of objects and the gravitational constant, with the formula F = mg close to the Earth's surface.
Gravitational pull and Influencing Factors
The option that determines gravitational pull is mass. According to Newton's Law of Gravity, anything that has mass attracts everything else that has mass. The gravitational force (F) between two objects can be determined by the equation F = G(M1M2)/r^2, where G is the gravitational constant, M1 and M2 are the masses of the objects, and r is the distance between the centers of the two objects. The force of gravity on an object near the Earth's surface is calculated as the mass of the object (m) multiplied by the acceleration due to gravity (g), which is F = mg.
Volume does not directly determine gravitational pull; rather, it is the total quantity of matter, or mass, within that volume that contributes to gravity. The acceleration due to gravity remains constant (g = 9.81 m/s^2 near the Earth's surface) regardless of the object's mass. While the force of gravity is relatively weak, it is sufficient to keep the planets in orbit around the sun, as demonstrated in Newton's Universal Law of Gravitation.
A bike that is coasting down a steep hill increases its speed from 8.0 m/s to 14 m/s. The length of the hill is 55 meters. How much time passes during the descent?
t=5s
it was correct on my do-now
so I hope it was useful for you
Answer:
Time, t = 5 seconds
Explanation:
It is given that,
Initial speed of the bike, u = 8 m/s
Final speed of the bike, v = 14 m/s
Length of the hill, d = 55 m
Firstly, we can find the acceleration of the bike. Let it is equal to a. It can be calculated using third equation of motion as :
[tex]a=\dfrac{v^2-u^2}{2d}[/tex]
[tex]a=\dfrac{(14)^2-(8)^2}{2\times 55}[/tex]
[tex]a=1.2\ m/s^2[/tex]
Let t is the time passes during the descent. It can be calculated using the first equation of motion as :
[tex]t=\dfrac{v-u}{a}[/tex]
[tex]t=\dfrac{14-8}{1.2}[/tex]
t = 5 seconds
So, the time passes during the descent is 5 seconds. Hence, this is the required solution.
scientific notation for 7890
the speed of sound is 344 m/s. you see a flash of lightning and then hear the thunder 1.5 seconds later. how far away from the lightning strike are you?
Answer: 516 m
Explanation:
Speed [tex]V[/tex] is defined as the distance traveled [tex]d[/tex] in a especific time [tex]t[/tex]:
[tex]V=\frac{d}{t}[/tex]
Where:
[tex]V=344 m/s[/tex] is the speed of sound
[tex]t=1.5 s[/tex] the time you hear the thunder after you see the flash of lightning
We need to find the distance at which you are from the lightning strike:
[tex]344 m/s=\frac{d}{1.5 s}[/tex]
Finding [tex]d[/tex]:
[tex]d=(344 m/s)(1.5 s)[/tex]
Finally:
[tex]d=516 m[/tex]
Final answer:
To calculate the distance of a lightning strike using the sound of thunder, multiply the time delay of 1.5 seconds by the speed of sound (344 m/s), giving an answer of 516 meters or approximately 0.516 kilometers.
Explanation:
When observing a lightning strike, we often witness the light (the flash) well before we hear the sound (thunder) due to the speed of light being much faster than the speed of sound. In the given scenario, if you hear thunder 1.5 seconds after seeing a flash, we can calculate the distance to the lightning strike by multiplying the time it took to hear the thunder by the speed of sound in air.
Since the speed of sound is approximately 344 m/s, we can estimate the distance to the lightning strike with the following calculation:
Distance = Speed of Sound × Time Delay
Distance = 344 m/s × 1.5 s
Distance = 516 m
Converted to kilometers, the lightning strike was approximately 0.516 km away from you.
A baseball is popped straight up into the air and has a hang-time of 6.25 S.
Determine the height to which the ball rises before it reaches its peak. (Hint: the
time to rise to the peak is one-half the total hang-time.)
Answer:
47.9 m
Explanation:
Given:
y₀ = 0 m
t = 6.25/2 = 3.125 s
v = 0 m/s
a = -9.8 m/s²
Find: y
y = y₀ + vt − ½ at²
y = 0 + (0)(3.125) − ½ (-9.8)(3.125)²
y = 47.9 m
We have that for the Question "A baseball is popped straight up into the air and has a hang-time of 6.25 S.
Determine the height to which the ball rises before it reaches its peak. (Hint: the time to rise to the peak is one-half the total hang-time.)" it can be said that Hence, the height to which the ball rises before it reaches its peak is
S=47.85m
From the question we are told
A baseball is popped straight up into the air and has a hang-time of 6.25 S.
Determine the height to which the ball rises before it reaches its peak. (Hint: the time to rise to the peak is one-half the total hang-time.)
Generally the Newtons equation for the distance is mathematically given as
[tex]s=ut+1/2at^2\\\\\ Where \\\\T=\frac{6.25}{2}\\\\T=3.125\\\\[/tex]
Therefore
[tex]s=0+1/2(9.8)(3.125)^2[/tex]
S=47.85m
Hence, the height to which the ball rises before it reaches its peak is
S=47.85m
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A scientific hypothesis starts with the lowest level of acceptance but can become stronger as they are used and survive repeated testing.
1)True
2)False
Answer:
True.
Explanation:
Hypotheses are supposed to be tested, to be proven correct. They usually start from a small thought without 100% correct, but as you do further testing, they become stronger.
Answer: 1)True
Explanation:
A scientific hypothesis is a statement which is based on the the direct observation of a scientific event, process or phenomena. It can be based on the assumptions. It is testified using appropriate scientific methodology.
The scientific hypothesis can be proved to be negative or false but repeated experimental trials can prove a hypothesis true and acceptable.
which compound is composed of oppositely charged ions
I believe your answer is Ionic solids.
The process which a solid changes to a liquid
Melting
Explanation:
This process is called melting in which a solid changes to a liquid
Which environmental change would most likely result in bullfrog offspring that are able to store more water than bullfrogs in previous generations?
Answer:
a drought
Explanation:
bullfrogs would only need to store more water if they would go longer periods of time without it - think about how cacti store all the water they can in desert, since there is not a lot of water there.
A 210-kg woorden raft floats on a lake. When a 75-kg man stands on the raft, it sinks 5.0 cm deeper into the water. When he steps off, the raft vibraties for a while. A. What is the frequency of vibration? B. What is the total energy of vibration? Hint: ignore damping.
Answer:
A: The frequency of the vibration is 1.3329 Hz
B: The total energy of the vibration is 18.39375 J
Explanation:
The force of the man his weight causes the raft to sink, and that causes the water to put a larger upward force on the raft. This extra force is a restoring force, because it is in the opposite direction of the force put on the raft by the man. Then when the man steps off, the restoring force pushes upward on the raft, and thus the raft – water system acts like a spring, with a spring constant found as follows:
k= F/x = ((75 kg) * (9.81 m/s²))/(5*10^-2 m) = 14715 N/m
The frequency of the vibration is determined by the spring constant (k) and the mass of the raft (210kg).
fn = 1/2π * √(k/m) = 1/2π * √(14715 / 210) = 1.3329 Hz
The frequency of the vibration is 1.3329 Hz
b)
Since the gravitational potential energy can be ignored, the total energy will be :
Etot = 1/2 k* A² = 1/2 * (14715 )*(0.05)² = 18.39375 J
The total energy of the vibration is 18.39375 J
A basketball rolls onto the court with a speed of
4
.
0
m
s
4.0
s
m
4, point, 0, space, start fraction, m, divided by, s, end fraction to the right, and slows down with a constant acceleration of
0
.
5
0
m
s
2
0.50
s
2
m
0, point, 50, space, start fraction, m, divided by, s, start superscript, 2, end superscript, end fraction over
1
4
m
14m14, space, m.
What is the velocity of the basketball after rolling for
1
4
m
14m14, space, m?
Answer:
5.48 m/s
Explanation:
We can find the final velocity of the basketball by using the SUVAT equation:
[tex]v^2 - u^2 = 2ad[/tex]
where
v is the final velocity
u = 4.0 m/s is the initial velocity
[tex]a=0.50 m/s^2[/tex] is the acceleration
d = 14 m is the distance covered
Solving the equation for v, we find:
[tex]v=\sqrt{u^2 +2ad}=\sqrt{4.0^2+2(0.50)(14)}=5.48 m/s[/tex]
8. If a car is going 10 m/s and 4 seconds later it is going 18 m/s, what is its acceleration!
Answer:
2 m/s²
Explanation:
Acceleration is change in velocity over change in time.
a = Δv / Δt
a = (18 m/s − 10 m/s) / 4 s
a = 2 m/s²
The acceleration of a car going 10 m/s and 4 seconds later it is going 18 m/s is 2m/s².
HOW TO CALCULATE ACCELERATION:
The acceleration of a moving body can be calculated using the following formula:a = (v - u)/tWhere;
a = acceleration (m/s²)v = final velocity (m/s)u = initial velocity (m/s)t = time (seconds)According to this question, a car is going 10 m/s and 4 seconds later it is going 18 m/s. The acceleration can be calculated as follows: a = (18m/s - 10m/s)/4a = 8/4a = 2m/s²Therefore, the acceleration of a car going 10 m/s and 4 seconds later it is going 18 m/s is 2m/s².Learn more about calculating acceleration at: https://brainly.com/question/19573976?referrer=searchResults
What is a difference between physical traits and personality traits?
A. Physical traits are mainly determined by a person's environment; personality traits are
determined by both a person's genes and environment.
B. Physical traits are mainly determined by a person's genes, personality traits are
determined by both a person's genes and environment.
C. Physical traits are mainly determined by a person's genes and environment;
personality traits not determined by either a person's genes or environment.
D. Physical traits are mainly determined by a person's genes; personality traits are
determined by genetically engineered food that a person eats.
Answer:
A physical trait is visible to the naked eye, such as, having six fingers; and a character trait is invisible to the naked eye, such as, being charming. Both can be subjective, for instance, claiming somebody has a big nose is a subjective comment about somebody's physical appearance.
The difference between physical traits and personality traits are that physical traits are mainly determined by a person’s genes, personality traits are determined by both a person’s genes and environment.
Answer: Option B
Explanation:
Physical traits are facial similarities, body language, nature of hairs and skins. Mostly the face of siblings and the children will have some similarities with their parents or other members in their family.
So, we can say that physical traits are mainly determined by person’s genes. While the personality traits determine a person’s character , hobbies, likes, dislikes, point of view etc.
Thereby, the personality traits will be coming from genes and also from the environment the person has been grown. Both genes and environment effect equally on a persons’ character and personality.
calculate the speed of the wave with the frequency of 10khz and wavelength of 2m
speed = wavelength × frequency
but the frequency was given to as
10khz ,
which means
[tex] {10}^{3} [/tex]
= 1000
so now frequency = 1000hz
substitute it into the equation
speed = 1000×2
speed = 2000ms^-1
The speed of the wave with the frequency of 10 kHz and a wavelength of 2 meters is 20,000 meters per second, or 20 km/s.
Explanation:To calculate the speed of a wave, we can use this simple physics formula: speed = frequency × wavelength. In this case, the frequency of the wave is 10 kHz (or 10,000 Hz) and wavelength is 2 meters. Knowing these values, we can substitute them into the formula.
Speed = 10,000 Hz × 2 meters
Therefore, the speed of the wave is 20,000 meters per second, or 20 km/s.
The speed of the wave with the frequency of 10 kHz and a wavelength of 2 meters is 20,000 meters per second, or 20 km/s.
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Liam and Melinda have completed one trial testing the freezing point of several solutions, but they cannot agree on what to do next in their experiment. What should be the next step in their investigation? A. repetition, completing more trials for each solution B. analysis, determining whether their data and precise and accurate C. further investigation, testing new solutions and comparing them to their original data D. replication, asking about their classmates’ findings to compare data
Answer:
A. repetition, completing more trials for each solution
Explanation:
In this experiment, the two differ in results that is why they ca not agree on the next step.This happens when experimental results do not confirm the hypothesis of the experiment.In such cases, you are required to assess the stages in the experiment which are- the hypothesis, the experimental stages,the analysis stage and the result stage.The key here is to go through the write up of the experiment to see the problems that cause the variations in results.
In this case where they were testing the freezing points of several solutions, there are four cognitive properties of a solution that affects the solvent. They are lowering of vapor pressure, lowering of freezing point, rise in boiling point or initiation of an osmotic pressure in the process.When they perform more trials for each solution, they will see if they carried out the experiment correctly.
Answer:
A. Repetition, completing more trials for each solution
Explanation:
Just got it right on Edg :)
d=1/2at^2
solve for a
Answer:
a = 2d / t²
Explanation:
d = ½ at²
Multiply both sides by 2:
2d = at²
Divide both sides by t²:
a = 2d / t²
The solution of the acceleration a would be (2dt²) by using the equation d=1/2at²
What are the three equations of motion?Newton provided three equations of motion.
This is how the first equation is presented.
v = u + at
The second equation is given as follows.
d= ut + 1/2×a×t²
Following is the third equation.
v² - u² = 2×a×d
Keep in mind that only uniform acceleration is supported by these equations. where the initial and final velocities, respectively, are u and v.
d is the object's overall distance traveled, and a represents its acceleration.
As given in the problem we have to solve the acceleration by using newtons second equation given that the initial velocity is zero
By using The second equation is given as follows.
d = ut + 1/2×a×t²
as u =0
d=1/2at²
a = d/(1/ 2t²)
a =2dt²
Thus, The solution of the acceleration a would be (2dt²) by using the equation d=1/2at²
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When a chemical reaction occurs,
A.) reactants interact to form products with different chemical and physical properties
B.) reactants interact to form products with different numbers of atoms
C.) products react to form several reactants with different chemical properties
Select the correct answer.
Based on the law of conservation of energy, which statement is false?
O A.
Energy is lost when machines don't work right.
OB. We can't add more energy to the universe.
O c. We can't destroy energy that exists in the universe.
O D.
Energy changes from one form to another.
Answer:
A. Energy is lost when machines don't work right.
Explanation:
Energy cannot be created nor destroyed, according to the Law of Conservation of Energy.
Which state of matter has the greatest amount of particle movement?
Answer:
The state of matter that has the most energy is gas.
Explanation:
In a solid, there is limited room for molecules to move around.
Answer:
The greatest amount of particle movement is in gaseous state of matter.
Explanation:
It is known that matter can be classified as solid, liquid and gas states. The molecules in each state exhibit vibrations or movement of particles will be occurring in them. The kinetic energy exhibited by the different states of matter depend upon the bond strength.
If the bond strength is more and if the particles are densely packed like in solids. So the gas state has least bond strength and they are loosely packed molecules and thus the particles can move freely with more kinetic energy.
9. If a rocket flies north 390 meters in 6 seconds, what is its velocity?
Answer:
65 m/s north
Explanation:
The velocity of an object is given by:
[tex]v=\frac{d}{t}[/tex]
where
d is the displacement of the object
t is the time interval needed for the displacement
For the rocket in this problem,
d = 390 m north
t = 6 s
So the velocity is
[tex]v=\frac{390}{6}=65 m/s[/tex] north
It is important to keep in mind that velocity is a vector, so it both has a magnitude (65 m/s) and a direction (which is equivalent to that of the displacement, so in this case north).
L
2.1.2 Quiz: Physical Fitness
Question 2 of 10
3 Points
A healthy body weight is associated with a low BMI.
O A. True
OB. False
We can confirm that the statement made in the question is in fact true, a healthy body weight is associated with a low BMI.
Why is a low BMI healthy?BMI is the acronym for "Body Mass Index". This is a measurement that indicates the fat contents of the body of the individual being measured. A low BMI is associated with healthy body weight as it indicated low levels of fat. Anything below 25% is considered to be acceptable, while anything below 15% is considered to be fit/athletic.
Therefore, we can confirm that this statement is in fact true, as a low BMI indicates low fat levels and therefore is associated with healthy body weight.
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The statement associating a low BMI with a healthy body weight is false. A healthy body weight, as indicated by BMI, falls within the 18-24.9 range. However, BMI is an imperfect measure and can be misleading due to its disregard for muscle mass, fat distribution, and bone density.
Explanation:The statement that a healthy body weight is associated with a low body mass index (BMI) is False. A healthy body weight, as indicated by BMI, falls within a range. A BMI ranging from 18-24.9 is considered normal weight, 25-29.9 is considered overweight, and a BMI greater than 30 is considered obese. However, BMI has its limitations. It does not account for muscle mass, fat distribution, or bone density, which can lead to inaccuracies in determining actual health status. A muscular person may have a high BMI but low body fat, while an individual with less muscle mass might have a lower BMI but higher body fat percentage.
An atom has 18 protons, 18 electrons, and 20 neutrons.
This atom has ?
a negative charge
an atomic number of 20
a mass number of 38
a positive charge
Answer:
mass number of 38
Explanation:
Charge is 0 - No. of protons is equal to nom.of electrons, so no charge
Atomic number is 18 - Atomic number is number of protons
Mass number is 38- mass number is number of protons AND neutrons
Answer:
a mass number of 38
Explanation:
X This atom has no a negative charge .
because, number of protons (18) & electrons (18) are same. so,This atom is neutral.
X This atom has an atomic number of 20.
Because, it has 18 protons. so, This atom has an atomic number of 18.
X This atom has a positive charge
because, number of protons (18) & electrons (18) are same.so,This atom is neutral.
Please I really need help
Answer:
10 Is the last one (D) 11 is the one you picked, or the third option. (C)
Explanation:
Earth’s gravity keeps the moon in orbit by pulling on it.
What does the moon’s gravity do?
A. pulls back on the Earth
B. can only pull on smaller objects such as asteroids but has no effect on the Earth
C. doesn´t affect anything
D. pushes the moon away from the Earth
Answer:
A. pulls back on the Earth, which is the main cause of the rise and fall of the ocean tides on Earth.
The moon’s gravity pulls back on the Earth. Therefore, option (A) is correct.
What is the moon's gravity?The Moon's gravity can be described as the acceleration due to gravity on the surface of the Moon. The value of g on the Moon can be calculated by considering the mass of the Moon and earth.
The mass of the Moon is equal to 7.342 x 10²² kg which is 1.2% of the mass of the earth and the radius of the Moon = 1.74 x 10⁶ m
Since the formula to calculate the value of g = GM/r2
The value of the g for the Moon is equal to 1.652 m/s² which is 16.7 % of the gravity of the earth.
The moon's gravity on the Earth is the reason for the rise and fall of ocean tides. The moon's gravitational pull arises two bulges of water on the oceans of the earth in which one where ocean waters face the moon and the pull is strongest and another where ocean waters face away from the moon and the pull is weakest.
Therefore, the gravity of the moon pulling back on the Earth is the correct option.
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The masses of two metal blocks are measured. Block A has a mass of 8.45 g and Block B has a mass of 45.87 g. How many significant digits are expressed in these measurements? What is the total mass of block A plus block B? What is the number of significant digits for the total mass?
Answer:
3 sig figs total mass is 54.32g
Explanation:
It is 3 sig figs because that is the accuracy that Block A was measured to
6. What does the slope of a velocity-time graph indicate?
The slope of a velocity-time graph represents the acceleration of an object.
Acceleration is the rate of change of velocity over time. A steeper slope indicates a greater acceleration, meaning the object is speeding up or slowing down more rapidly.
A horizontal line on the graph, where the slope is zero, indicates constant velocity, implying no acceleration. If the slope is negative, the object is decelerating or moving in the opposite direction. In summary, the slope of a velocity-time graph provides valuable information about how an object's velocity changes over time, offering insights into its acceleration or deceleration behavior.
You throw a ball upward with a speed of 14 m/s. What is the acceleration of the ball after it leaves your hand?
Answer:
g = -9.8 m/s²
Explanation:
Gravity is the only force pulling on any object in free fall. Gravity near earth's surface pulls with an acceleration g.
The acceleration of the ball is -9.8 meter per sec square acting as deceleration when the ball left the hand after being thrown upwards.
Explanation:
The ball is thrown with a speed of 14 m/s and the moment it comes into the projectile, gravity starts to work on it. The gravity applies the uniform acceleration of 9.8 m/s^2.
This acceleration is in the form of deceleration [the negative acceleration] is termed as the deceleration. And here, the ball is thrown opposite to the gravity and hence the motion is against the gravity, the acceleration becomes -9.8 m/s^2.
A car in motion has kinetic energy. What happens to the kinetic energy when the car brakes to a stop? The kinetic energy is transformed into potential energy ready to be released when the car starts back up. The kinetic energy is lost since energy is not conserved. The kinetic energy is transformed into heat energy evident by the warmth of the tires and is dissipated. The kinetic energy is still there, it is just not observable.
When a car brakes to a stop, its kinetic energy is transformed primarily into thermal energy due to friction. The brakes and tires may become warm as a result of this energy conversion. Energy is neither lost nor does it become unobservable potential energy; it simply changes form in accordance with the law of conservation of energy.
Explanation:When a car brakes to a stop, its kinetic energy is transformed into other forms of energy. This is a fundamental concept in physics related to the conservation of energy, which tells us that energy cannot be created or destroyed, only transformed from one form to another. In the case of a car stopping, the kinetic energy is mostly converted into thermal energy due to the friction between the car's brakes and wheels. This energy transfer can cause the brakes and tires to warm up, and it is why they may feel hot after use. Additionally, some of the energy may be transferred to the surroundings as the car interacts with the air, causing air movement and sound.
The explanation that kinetic energy is transformed into potential energy to be used later is incorrect. Potential energy is related to an object's position in a gravitational field, not its motion. Thus, when the car stops, its kinetic energy does not become potential energy. Similarly, saying that the kinetic energy is still there but not observable is also incorrect, as the kinetic energy has been converted into other forms. The idea that kinetic energy is lost and not conserved is also a misconception because energy conservation is a fundamental law of physics.
Final answer:
When a car brakes to a stop, the kinetic energy is transformed into heat energy through friction.
Explanation:
When a car brakes to a stop, the kinetic energy of the car is transformed into heat energy. The brakes use friction to reduce the car's speed, and as a result, the kinetic energy is converted into heat energy. This can be observed by the warmth of the tires and the fact that the brakes can become very hot after coming to a stop.
A rock is dropped from the edge of a cliff 15.0 m high. How long does it take to reach the bottom of the cliff?
Answer:
1.75 s
Explanation:
The vertical position of the rock at time t is given by:
[tex]y(t) = h +ut - \frac{1}{2}gt^2[/tex]
where
h = 15.0 m is the initial height
u = 0 is the initial velocity
g = 9.8 m/s^2 is the acceleration of gravity
t is the time
When the rock reaches the bottom of the cliff,
y(t) = 0
Substituting this condition into the previous equation, we can find the time at which the rock reaches the bottom of the cliff:
[tex]0 = h - \frac{1}{2}gt^2\\t= \sqrt{\frac{2h}{g}}=\sqrt{\frac{2(15.0)}{9.8}}=1.75 s[/tex]
What must you do to calculate a meaningful value of distance from the following equation?
d= (0.90km) + (12.5km)/h x (31.5s)
-Convert the kilometers to meters.
-Convert the kilometers to miles.
-Drop the symbols for the units.
-Convert all the times to either hours or seconds.
Answer:
Convert all the times to either hours or seconds
Explanation:
One time unit is in hours, and the other is in seconds. In order to do the math, the units need to be the same. So you either need to convert hours to seconds, or seconds to hours.
Answer:
-Convert all the times to either hours or seconds.
Explanation:
Given,
[tex]d= (0.90km) + (12.5km/h) \times (31.5s)[/tex]
While doing a mathematical calculation all the units should be same otherwise the result will not be correct. Here two units of time i.e. second and hour are being used. We will convert the second to hour by dividing it by 3600 as there are 3600 seconds in one hour. The distance will be,
[tex]d= (0.90km) + (12.5km/h) \times (\frac{31.5}{3600}h)[/tex]
[tex]d= 0.90 + 12.5 \times \frac{31.5}{3600}[/tex]
[tex]d= 0.90 + \frac{393.75}{3600}[/tex]
[tex]d= 0.90 + 0.109[/tex]
[tex]d= 1.009 km[/tex]
The rate at which current flows is measured in .
Answer:
Ampere
Explanation:
The ampere is the unit of measurement in the international system. Its equal to a coulomb/second. It can be describe as the rate of charges flowing throught a conductor
If you're talking water current, it could be gallons per hour, liters per second, acre feet per month, feet per second, mile per hour, etc. Any time rate of volume or distance.
If you're talking electrical current, then the unit is almost certainly 'Amperes' .