Answer:
Acceleration = -3m/s²
Explanation:
Given the following data;
Initial velocity = 19m/s
Final velocity = 3m/s
Time = 2secs
To find the acceleration;
In physics, acceleration can be defined as the rate of change of the velocity of an object with respect to time.
This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time. Mathematically, acceleration is given by the equation;
[tex]Acceleration (a) = \frac{final \; velocity - initial \; velocity}{time}[/tex]
Substituting into the equation, we have;
[tex]a = \frac{3 - 9}{2}[/tex]
[tex]a = \frac{-6}{2}[/tex]
Acceleration = -3m/s²
The value for her acceleration is negative because she is decelerating i.e her final velocity is lower than her initial velocity.
Select the correct answer from each drop-down menu. What types of energy are involved in a chemical reaction? is the energy required for a chemical reaction to take place, and is the energy associated with every substance.
Box one choices are: Activation energy, chemical energy and released energy
Box 2 choices are: absorbed energy, chemical energy and released energy
Answer: box one is chemical energy and box 2 is absorbed energy
Explanation:
Answer:
CHEMICAL ENERGY AND ABSORBED ENERGY srry caps on
Explanation:
your welcomeッ
On a building site, a crane lifts a load of bricks. The lifting force is 2750N and the bricks are raised to a height of 9.0m. Calculate the work done by the crane in lifting the bricks.
Answer:
the work done in raising the load is 24,750 J
Explanation:
Given;
load lifted by the crane with a force, F = 2750 N
height through which the load was raised, h = 9.0 m
The work done by the crane in raising the load is calculated as;
W = F x h
W = 2750 x 9
W = 24,750 J
Therefore, the work done by the crane in raising the load is 24,750 J
The portion of a sound wave with higher-than-normal pressure is called a(n)________
Answer:
Condensation
Explanation:
Increased pressure is called condensation or compressions because they are regions of high air pressure whilst rarefractions are low air pressure.
In order for maximum work to be done...
free lil peezy and drake is kool
Answer:
For constant traveled distance and applied forces, apply the for parallel to the direction of the movement.
Explanation:
[tex]W = F.d = |F||d|cos(\theta)\\[/tex]
There are 3 components in the amount of work produced when applying a force to an object.
1. The amount of force applied
2. The distance that the object is traveled
3. The angle between the force vector and the distance vector
To get the maximum amount of work for a constant force and distance, the force needs to be along the distance traveled [tex]=> \theta = 0[/tex]If the angle and the distance are constant, the only way is to apply a larger force in magnitudeIf the angle and the force are constant, increasing the distance traveled will result in higher amount of work produced.what is meant by the fact that length of a object is 4 metre
Answer:
It simply means that the longest side of the object is 4 m that is 400cm..
Explanation:
___________
It took 3.5 hours for a train to travel the distance between two cities at a velocity of 120mi/h. How many miles lie between the two cities?
Answer:
420 miles
Explanation:
3.5 * 120 mi/h = 420 miles
Which space rock is easiest to study and what do we typically learn from
them?
A student slides a rock along the flat surface of a frozen pond. The rock starts to slow down after several seconds. Construct an explanation using Newton's Laws that describes why the rock begins to decelerate.
Answer:
When the student slides the rock along the flat surface of the frozen pond, according to Newton's second law of motion, the rock is given an initial velocity of motion. According to Newton's first law of motion, the rock will continue to slide indefinitely unless it is slowed or stopped by an opposite force. According to Newton's third law, the rock experiences a reaction force from the force of friction of the ice which slows it down at a rate given by Newton's second law of motion and the rock is seen to decelerate
Explanation:
Newton's first law of motion, states that an object will remain at rest or maintain a uniform motion in a straight line, unless impressed upon by an external force
Newton's second law states that an applied force is equal to the rate of change of momentum it produces
Newton's third law states action and reaction are equal and opposite.
energy transfered electrically is measured in _____. what one word completes the sentence?give the fullname not symbol.
Answer:
joules
Explanation:
The electric energy transferred to a resistor in a time period is equal to the electric power multiplied by time, E=Pt, and can also be calculated using E=I2Rt. Electric companies measure their energy sales in a large number of joules called a kilowatt hour (kWh) which is equivalent to 3.6×106 J.
Air only has a density of 1.3kg/m². What is the mass of
3m^3 of air?
Answer:
m = 3.9 [m³]
Explanation:
We must remember that the density of the substance is defined as the relationship between mass over volume. That is expressed in the following equation:
[tex]Ro = m/V[/tex]
where:
Ro = density = 1.3 [kg/m³]
m = mass [kg]
V = volume = 3 [m³]
Now replacing the values.
[tex]m =Ro*V\\m = 1.3*3\\\\m=3.9[m^{3}][/tex]
Can someone help my with my Physics lab pleaseeeee
Answer:
whats the question
Explanation:
where your question
calculate the energy of 1kg of concrete from 20⁰c to 30⁰c
Answer:
9 kilojoules of energy are stored in a kilogram of concrete due to sensible heat.
Explanation:
In this exercise we need to determined the sensible heat store in a kilogram of concrete due to a change in temperature. Sensible heat ([tex]Q[/tex]), measured in kilojoules, is defined by the following expression:
[tex]Q = m\cdot c\cdot (T_{f}-T_{o})[/tex] (1)
Where:
[tex]m[/tex] - Mass, measured in kilograms.
[tex]c[/tex] - Average specific heat of concrete, measured in kilojoules per kilogram-degree Celsius.
[tex]T_{o}[/tex], [tex]T_{f}[/tex] - Initial and final temperatures of concrete, measured in degrees Celsius.
If we know that [tex]m = 1\,kg[/tex], [tex]c = 0.9\,\frac{kJ}{kg\cdot ^{\circ}C}[/tex], [tex]T_{o} = 20\,^{\circ}C[/tex] and [tex]T_{f} = 30\,^{\circ}C[/tex], then the energy store in a kilogram of concrete is:
[tex]Q = (1\,kg)\cdot \left(0.9\,\frac{kJ}{kg\cdot ^{\circ}C} \right)\cdot (30\,^{\circ}C-20\,^{\circ}C)[/tex]
[tex]Q = 9\,kJ[/tex]
9 kilojoules of energy are stored in a kilogram of concrete due to sensible heat.
When the force applied to an object is increased, how will the rate of acceleration change if the mass it is applied to remains constant?
Answer:
Because of the formula a = F/m
Explanation:
The force and mass affect the acceleration of the object, because of the formula above.
A roller coaster typically takes 6.5 s to come to a complete stop from traveling at 30 m/s. If it has a force of 540 N, what is the mass of the coaster
Answer:
117 kg
Explanation:
Step one:
given data
time t= 6.5s
velocity v= 30m/s
Force F= 540N
Required
the mass m
Step two:
Recall from the expression
Ft= mv
make m subject of the formula
m= Ft/v
substitute
m= 540*6.5/30
m=3510 /30
m=117 kg
The weight of a body varies from location to location. Where would the weight of the body be least?. Single choice.
Explanation:
The weight of a body depends on the acceleration due to gravity at a particular place.
Weight is a form of force on a body but this type depends on the gravitational force from places to places.
Weight = mass x acceleration due to gravity.
Assuming that mass is constant, the acceleration due to gravity is directly proportional to the weight.
The higher the acceleration due to gravity of a body, the more it weighs and vice - versa.
A photographer might use a light meter to make sure she has enough light for
a good photograph. The meter absorbs light and provides a current that
moves the needle on the meter. How does this phenomenon support the
particle model of light?
A. It is the result of constructive interference.
B. It is the result of the photoelectric effect.
C. It is the result of the diffraction of a beam of light.
D. A light meter is a blackbody radiator.
Answer:
It is the result of the photoelectric effect.
Answer:
B
Explanation:
Plz help me
Thank you so much
Answer:
I believe its the blue, sorry if I'm wrong
As a stop light changes from red to green, a car starts to cross through the intersection. An instant before it begins to move, its velocity is zero. Must its acceleration at that time also be zero. Why or why not
Answer:
Yes, the acceleration at that time is also zero because the velocity is zero.
Explanation:
To answer the question given above, we shall determine the acceleration of the car at time 't' when the velocity is zero.
From the question given above, the following data were obtained:
Velocity (v) = 0 m/s
Time (t) = t
Acceleration (a) =?
Acceleration is defined as:
Acceleration (a) = Velocity (v) / time (t)
a = v/t
a = 0/t
a = 0
From the above illustration, we can see that the acceleration is zero irrespective of the time 't'.
Therefore, the acceleration of the car will be zero since the velocity of the car at time 't' is zero.
heres some more money
Answer: Brain?
Explanation:
I could be wrong but i'm pretty sure the answer is brainiest
Someone can help me pls
Is physical science class
Answer:
I can't see the picture
Explanation:
The images below are models that represent the reactants and products of a chemical reaction.
Reactants Products
Based on the models, was mass conserved in this chemical reaction?
A.
No, because the purple atom formed two bonds in its reactant molecule and only one bond in its product molecule.
B.
No, because the reactants are made up of different types of molecules than the products.
C.
Yes, because the number of reactant molecules is the same as the number of product molecules.
D.
Yes, because the number of each type of atom is the same in the products as it is in the reactants.
Explanation:
In a chemical reaction, when mass is conserved , the number of atoms or moles of the reactants must be equal to the number of moles or atoms in the products side.
From the diagram, we should carefully look to see if the number of atoms that makes up the reactants are equal to those on the product side.
For example:
A + B → AB
Here, mass is conserved because, on the reactant side, we have 1 atom of A and on the product side we have 1 atom of A
For B, on the reactant side, we have 1 atom of B and on the product side, we have 1 atom of B.
Answer:
Yes, because the number of each type of atom is the same in the products as it is in the reactants.
Explanation:
NEED ASAP WILL GIVE BRAINLIEST
What is the change in internal energy if 90 J of thermal energy is added to a
system, and the system does 30 J of work on the surroundings?
A. 60J
B. -130J
C. 130J
D. -60J
Answer:
a- the answer is 60J
apologies if its wrong
Answer: A) 60
Explanation:
If you have a mass of 15kg , what is your weight on earth?
What happens to the temperature during an endothermic reaction? ANSWERS; The temperature stays constant. The temperature will decrease (get colder). The temperature will increase (get warmer)
Answer:
The temperature will decrease (get colder).
Explanation:
Enthalpy changes are heat changes accompanying physical and chemical changes. The enthalpy change is the difference between the sum of the heat contents of products and the sum of heat contents of reactants.
For an endothermic change, heat is absorbed for the reaction. The surrounding becomes colder at the end of the reaction and so is the reaction itself. The right choice is that the temperature will decrease.A friction-less pulley in the shape of a solid cylinder of mass 2.90 kg and radius 30.0 cm is used to draw water from a well. A bucket of mass 1.90 kg is attached to a cord wrapped around the cylinder. If the bucket starts from rest at the top of the well and falls for 3.70 seconds before hitting the water, how deep is the well
Answer:
[tex]s=-38.332m[/tex]
Explanation:
From the question we are told that
Cylinder of mass [tex]m=2.90 kg[/tex]
Radius [tex]R=30.0 m[/tex]
Mass of bucket [tex]M_b= 1.90 kg[/tex]
Fall time [tex]T_f= 3.70 seconds[/tex]
Generally the tension the bucket is mathematically given by
[tex]T-mg=ma[/tex]
For cylinder
[tex]T=I*\alpha[/tex]
where
[tex]I=1/2mR^2[/tex]
[tex]a=R*\alpha[/tex]
Giving
[tex]T=-1/2mR\alpha[/tex]
Therefore
[tex]a=\frac{-mg}{m+1/2m}[/tex]
[tex]a=\frac{-(1.9*9.81)}{1.9+0.5*(2.9)}[/tex]
[tex]a=-5.563880597 \approx -5.6m/s^2[/tex]
Generally the Newton's equation for motion is mathematically represented as
[tex]s=ut+1/2at^2[/tex]
[tex]s=0(3)+1/2*-5.6*(3.7)^2[/tex]
[tex]s=-38.332m[/tex]
Please Help Me!!!........
Answer:
B: A material with relatively weak bonds between it's particle can be shped in to a thin sheet.
Explanation:
Compare these two waves!!!! RIGHT NOW I DONT HAVE ALOT OF TIME
Answer:
wave D has higher frequency then wave c
wave C has longer wavelength
wave D has a higher pitch
Explanation:
Answer: Isn't frequency the amount of times something happened? So I'd say A also E
Explanation:
(Don't rely I'm not that smart)
A cyclist travelled 32 kilometers for both the 1st and 2nd hours. He took a 30 minute break to eat his lunch. He then travelled 15 kilometers for the final 3rd hour. What is the cyclist's average speed?
Answer:
The cyclist's average speed is 13.43 [tex]\frac{km}{h}[/tex]
Explanation:
Speed is a quantity that expresses the relationship between the space traveled by an object and the time used for it. That is, speed is the magnitude that expresses the variation in position of an object and as a function of time, which would be the same as saying that it is the distance traveled by an object in the unit of time.
Average speed relates the change in position to the time taken to effect that change:
[tex]speed=\frac{change in position}{time} =\frac{distance}{time}[/tex]
In this case:
total distance traveled= 32 km + 15 km= 47 kmtotal time= 3 hours that the cyclist travels + 30 minutes of rest = 3 hours + 0.5 hours (being 60 minutes equal to 1 hour, then 30 minutes equals 0.5 hours) = 3.5 hoursReplacing:
[tex]speed=\frac{47 km}{3.5 h}[/tex]
and solving, you get:
speed= 13.43 [tex]\frac{km}{h}[/tex]
The cyclist's average speed is 13.43 [tex]\frac{km}{h}[/tex]
8. A jaguar runs 4200 meters at the speed of 400 meters per minute. How
much time did this take? (You can use the speed triangle if it helps! Write
the formula, plug in the numbers, and write the answer with a box around it
Answer:
10.5min
Explanation:
Given parameters:
Distance = 4200m
Speed = 400m/min
Unknown:
Time taken for this run = ?
Solution:
Speed is the distance divided by the time taken.
Speed = [tex]\frac{distance }{time }[/tex]
Time = [tex]\frac{distance}{speed }[/tex]
Now insert the parameters and solve;
Time = [tex]\frac{4200}{400}[/tex] = 10.5min
The moving part of a speaker goes in and out 400 times per second. The frequency of the sound produced is:
a
4 hertz.
Ob
40 hertz.
400 hertz.
4,000 hertz.