Answer:
Explanation:
s(t) = 5t³-2t²+9
Instantaneous velocity v = ds / dt
v = ds/dt = 15t²-4t
Putting t = 7
v = 15 x 7² - 4 x 7
= 707
Instantaneous velocity at t = 7
is 707 unit .
Please help asap. A soccer player can kick a 0.370 kg football at 55 km/h. How much work does the soccer player have to do on the ball in order to give it that much kinetic energy?
Answer: 43.2 J
Explanation:
Work = change in KE
initial KE = 0
final KE = 1/2mv^2 = 1/2(0.370 kg)(15.2778 m/s)^2 = 43.2 J
i'm not sure about sig figs though
find the molecular formula of the following
Answer: hello i am a hacker
Explanation:
magnesium sulphate=(24*1)+(32*1)+(16*4)=120 water=H2O=(1*2)+(1*16)=18 carbon dioxide=CO2=(12*1)+(16*2)=44 ammonia=NH3=(14*1)+(1*3)=17 alminiumsulphate=AL2(SO4)3=(26*2)+(32*3)+(12*16)=340 hydrogen peroxide=H2O2=(1*2)+(16*2)=34 zinc sulphate=ZNSO4=(65*1)+(32*1)+(16*4)=161
A 140-Hz sound travels through pure carbon dioxide. The wavelength of the sound is measured to be 1.92 m. What is the speed of sound in carbon dioxide?
Answer:
V = 268.8 m/s
Explanation:
The speed of a wave in general is given by the following formula:
V = fλ
where,
V = Speed of that wave
f = Frequency of the wave
λ = wavelength of the wave
In this case we have a sound wave, travelling across carbon dioxide. The properties of sound wave are as follows:
V = Speed of Sound in Carbon dioxide = ?
f = frequency of sound wave = 140 Hz
λ = wavelength of sound wave = 1.92 m
Therefore,
V = (140 Hz)(1.92 m)
V = 268.8 m/s
The transfer of charge from clouds to the earth or cloud to cloud is called
That's called "lightning".
Answer:
The lightning itself is the transfer of charge from one region of a cloud to another or between the cloud and Earth. The narrow channel within which the flash of lightning occurs is heated suddenly to ~ 30,000 K, with essentially no time to expand.
Explanation:
Hope it helps
Which refers to the rate of change in velocity?
O speed
O acceleration
O direction
O magnitude
Answer:
acceleration is the answer
Answer:
Acceleration
Explanation:
a 6 letter word a way of explaining an object or event using a set of facts
Explanation:
A theory is a way of explaining an object or event using a set of facts.
1. The electric field strength between two parallel plates separated by 6.00 cm is 7.50 × 104 V/m . (a) What is the potential difference between the plates? (b) The plate with the lowest potential is taken to be zero volts. What is the potential 1.00 cm from that plate and 6.00 cm from the other?
Answer:
a)4500V
b)750V
Explanation:
Given:
Distance between the plate=
6.00 cm
We need to convert to m
Then the Distance between the plate=
0.06m
electric field strength between two parallel plates =
7.50 × 104 V/m .
Then E= 7.50 × 104 V/m .
(a) What is the potential difference between the plates?
potential difference between the plates can be calculated using the formula below
Δ Vab=ED
Where E is the given electric field strength
D= The Distance between the plate
ΔVab=7.50 × 10⁴V/m ×
0.06m
= 4500V
(b) The plate with the lowest potential is taken to be zero volts. What is the potential 1.00 cm from that plate and 6.00 cm from the other?
the potential 1cm from the zero volt plate
Then the 1cm must be converted to m
= 0.01m
Let us say plate A as the plate at 0 volts:
The potential increases linearly going from plate A (0 V) to plate B (4500V).
Therefore,if the potential difference between A and B, separated by 6 cm, is 4500 V, then the potential difference between A and a point located at 1 cm from A is can be calculated also
If the plate with Lowest potential is taken to be zero then
=ΔVab=Vab-Vb=Va-0=Va=ED
Va=7.50 × 10⁴V/m × 0.01=750V
As a new electrical technician, you are designing a large solenoid to produce a uniform 0.170 T magnetic field near its center. You have enough wire for 3800 circular turns, and the solenoid must be 1.60 m long and 20.0 cm in diameter. What current will you need to produce the necessary field?
Answer:
Explanation:
Magnetic field = permeability x turn density x current
Magnetic field = 0.22T
turn density = 4150 /1.6 = 2593.75 t/m
permeability : µ = k µ°
µ°= 4 π 10^-7
k = 1
I = 0.22 / 4 π 10^-7 * 2593.75 = 0.22 10^7 /32594 = 67.497 A
Ratan took a thin, solid piece of material. When he put it in water, it rose and floated. He took it out of the water and cut out holes in it as shown below. When Ratan puts the material with holes back in the water, what will happen?
Answer:
The material will still remain afloat.
Explanation:
The fact that the material floated on water as a solid piece means that the material is less dense than water. When a material is less dense than another liquid material, the material floats in the denser material. Cutting holes in the material will not reduce the buoyancy of the material. If the material had not floated as a single solid piece, then it will be said to be denser than the liquid material, and in such a case, if a strategic hole is cut on it to reduce its weight while maintaining its immediate volume, then it can be made to float. This is the principle behind metal floating ships.
Two small, identical conducting spheres repel each other with a force of 0.035 N when they are 0.35 m apart. After a conducting wire is connected between the spheres and then removed, they repel each other with a force of 0.055 N. What is the original charge on each sphere? (Enter the magnitudes in C.)
Explanation:
Given:
distance between two sphere =0.35 m
Electrical repel force =0.035 N
Electrical repel force after connecting wire =0.055 N.
The electrical force between the two spheres:
[tex]F=k \frac{q_{1} q_{2}}{r^{2}}[/tex]
The electrical force between the two spheres after the wire is attached and removed:
[tex]F=k \frac{q^{2}}{r^{2}}[/tex]
[tex]q^{2}=\frac{F r^{2}}{k}[/tex]
[tex]q=r \sqrt{\frac{F}{k}}=0.35 \times \sqrt{\frac{0.055}{8.99 \times 10^{9}}}=6.46 \times 10^{-7} \mathrm{C}[/tex]
So the total charge of the two spheres [tex]=2 q=2 \times 6.46 \times 10^{-7}=1.29 \times 10^{-6} \mathrm{C}[/tex]
Then before connecting the wire, one sphere charge was [tex]q[tex] and the charge of the other sphere was [tex]\left(1.29 \times 10^{-6}-q\right)[/tex]
The electrical force between the two spheres before connecting the wire:
[tex]F=k \frac{q\left(1.29 \times 10^{-6}-q\right)}{r^{2}}[/tex]
[tex]q\left(1.29 \times 10^{-6}-q\right)=\frac{F r^{2}}{k}=\frac{0.035 \times(0.35)^{2}}{8.99 \times 10^{9}}=0.348 \times 10^{-12}[/tex]
[tex]-q^{2}+\left(1.29 \times 10^{-6}\right) q-\left(0.348 \times 10^{-12}\right)=0[/tex]
[tex]-q^{2}+\left(1.29 \times 10^{-6}\right) q-\left(0.348 \times 10^{-12}\right)=0[/tex]
Which statement describes dynamic equilibrium? A. The forces on an object in motion are balanced. B. An object is accelerating due to forces acting on it. C. The forces on an object are unbalanced. D. The forces on a stationary object are balanced.
Answer: A. The forces on an object in motion are balanced.
Explanation:
The dynamic equilibrium is defined as the phase when an object moves at a constant velocity such that all forces on the object are balanced.
Simple case of dynamic equilibrium: A horizontal force is applied to an object making it run with a constant velocity across a surface.
Hence, the statement describes dynamic equilibrium is " The forces on an object in motion are balanced. "
So, the correct option is "A".
Answer:
Hope this helps!
2. When backing straight or to the right: a. Position your right hand on the back of the passenger seat. b. Grip the steering wheel at the 12 o’clock position with your left hand. c. Move the wheel left or right in the direction in which you want the rear of the vehicle to go. d. All of the above
Answer:
Option d = all of the above.
Explanation:
This question is more of a driving lesson or tutorial Question and not that scientific, it is logical and the "rule" attached to reversing and driving that is operating of vehicles especially cars, trucks and so on.
All the options given in the Question from option 'a' to option 'c' are all correct when driving backwards that is reversing or backing . Driving backward(backing or reversing) is not as easy as during forward (drive mode).
=> " Position your right hand on the back of the passenger seat. Grip the steering wheel at the 12 o’clock position with your left hand"
REASON: FOR BALANCING.
=> " Move the wheel left or right in the direction in which you want the rear of the vehicle to go."
The above, given in the Question are all correct.
When backing straight or to the right, all of the mentioned options are correct and recommended practices are to Position your right hand on the back of the passenger seat. The correct option is option d.
a) Position your right hand on the back of the passenger seat: This is a technique used by some drivers to help them have a better sense of the vehicle's position and reference point while backing up.
b) Grip the steering wheel at the 12 o'clock position with your left hand: This hand position allows for better control and maneuverability of the steering wheel while backing up.
c) Move the wheel left or right in the direction in which you want the rear of the vehicle to go: This is the fundamental principle of steering while backing up. By turning the wheel in the desired direction, you can guide the rear of the vehicle in that direction.
Therefore, These practices can assist in improving control, visibility, and maneuverability while backing up, ensuring a safer and more effective backing maneuver. The correct option is option d.
To know more about the principle of steering:
https://brainly.com/question/29458022
#SPJ6
How much work is done when 0.0042 C is moved through a potential difference of 12.0 V? Use W = qV A. 0.050 J B. 0.00035 J C. 2900 J D. 12 J
Answer:
Work done by charge (W) = 0.050 (Approx)
Explanation:
Given:
Charge (q) = 0.0042 C
Potential difference(V) = 12.0 V
Find:
Work done by charge
Computation:
Work done(W) = qV
Work done by charge (W) = (0.0042)(12)
Work done by charge (W) = 0.0504
Work done by charge (W) = 0.050 (Approx)
Answer:
Work done by charge (W) = 0.050 (Approx)
Explanation:
Charge (q) = 0.0042 C
Potential difference(V) = 12.0 V
Find:
Work done by charge
Computation:
Work done(W) = qV
Work done by charge (W) = (0.0042)(12)
Work done by charge (W) = 0.0504
Work done by charge (W) = 0.050 (Approx)
How will you connect 3 cells each of value 2V to give a total of 3V * Two in parallel with one in series Two in series with one in parallel All in parallel All in series
Answer:
two of them in series with one in parallel
Explanation:
When two or more batteries are connected in
(a) series: the total voltage produced is equal to the sum of the voltages on each of the batteries. For example, if two batteries A and B of 3V and 2V respectively are connected in series, then the total voltage produced is
3V + 2V = 5V
(b) parallel: the total voltage produced is equal to the voltage on any one of the batteries. As a mention, only batteries of the same voltage should be connected together in parallel. For example, if two batteries A and B each of 4V are connected together in parallel, then the total voltage produced is 4V.
If these batteries are not of the same voltage, then the one of larger voltage will charge the one of the lower voltage until they both have the same voltage. That means that their eventual voltage will be the average of their voltages. For example, if two batteries A and B of 3V and 2V respectively, are connected in parallel, their total voltage will be,
(3V + 2V) / 2 =2.5V
Now, from the question.
Since there are three cells each of value 2V.
=>If we connect two of them in series, the total voltage from those two cells will be 2V + 2V = 4V
=>If we then connect this series connection in parallel with the third cell, then we have a parallel combination of 4V and 2V. Since they have different voltages, then the total voltage will be the average of the two voltages. i.e
(4V + 2V) / 2 = 6 / 2 = 3V
Therefore, to have a total of 3V from three cells each of 2V, we need to connect two of them in series with one in parallel
help me helpppp the last words are experience a total
Answer:
False
Explanation:
Total internal reflection is a condition that occurs when light travels from dense medium to less dense medium.
From the table given in the question above,
Refractive Index of Whale oil = 1.460
Refractive Index of vacuum = 1
From the above, we can see that the whale oil has a higher Refractive Index than vacuum. This implies that the whale oil is denser than the vacuum.
Therefore, total internal reflection will occur when light travels from whale oil to vacuum because the whale oil is denser than the vacuum.
A classroom measures 3 m X 4m x 6 m.
Calculate the volume of air in the room. Give your answer in
a
cubic metres (mº).
Ted throws an object straight up into the air with an initial velocity of 54 ft/s from a platform that is 40 ft above the ground. Use the formula h(t)=−16t2+v0t+h0, where v0 is the initial velocity and h0 is the initial height. How long will it take for the object to hit the ground?
Answer:
The time it will take for the object to hit the ground will be 4.
Explanation:
You have:
h(t)=−16t²+v0*t+h0
Being v0 the initial velocity (54 ft/s) and h0 the initial height (40 ft) and replacing you get:
h(t)=−16t²+54*t+40
To know how long it will take for the object to touch the ground, the height h(t) must be zero. So:
0=−16t²+54*t+40
Being a quadratic function or parabola: f (x) = a*x² + b*x + c, the roots or zeros of the quadratic function are those values of x for which the expression is 0. Graphically, the roots correspond to the points where the parabola intersects the x axis. To calculate the roots the expression is used:
[tex]\frac{-b+-\sqrt{b^{2}-4*a*c } }{2*a}[/tex]
In this case you have that:
a=-16b= 54c= 40Replacing in the expression of the calculation of roots you get:
[tex]\frac{-54+\sqrt{54^{2}-4*(-16)*40 } }{2*(-16)}[/tex] Expresion (A)
and
[tex]\frac{-54-\sqrt{54^{2}-4*(-16)*40 } }{2*(-16)}[/tex] Expresion (B)
Solving the Expresion (A):
[tex]\frac{-54+\sqrt{5476 } }{2*(-16)}= \frac{-54+74}{2*(-16)}=\frac{20}{2*(-16)}=\frac{20}{-32}= -\frac{5}{8}[/tex]
Solving the Expresion (B):
[tex]\frac{-54-\sqrt{5476 } }{2*(-16)}= \frac{-54-74}{2*(-16)}=\frac{-128}{2*(-16)}=\frac{-128}{-32}= 4[/tex]
These results indicate the time it will take for the object to hit the ground can be -5/8 and 4. Since the time cannot be negative, then the time it will take for the object to hit the ground will be 4.
Answer:
4 seconds
Explanation:
i checked on the test and the other person was right give them brainliest
can someone proofread my Big freeze theory of the universe? does it make sense?
Answer:
Yes great job it was well written!:)
A piano has a mass of 99 kg. What is the weight of the piano?
A. 1030 N
B. 842 N
C. 1129 N
D. 970 N
Help!!
Answer:
[tex]D.\ 970\ N[/tex]
Explanation:
Given:
Mass of Piano: 99kg
Required:
Calculate its weight
The weight of an object is calculate as thus;
[tex]Weight = Mass\ (m) * Acceleration\ due\ to\ gravity\ (g)[/tex]
[tex]m = 99kg[/tex] and [tex]g = 9.8m/s^2[/tex]
The formula becomes
[tex]Weight = 99kg * 9.8m/s^2[/tex]
[tex]Weight = 970.2\ kgm/s^2[/tex]
[tex]Weight = 970.2\ N[/tex]
[tex]Weight = 970\ N[/tex] Approximated
Hence, the weight of the piano is 970N
A mass of 1.15 kg of air at 111 kPa and 27 C is contained in a gas-tight, frictionless piston cylinder device. The air is now compressed to a final pressure of 0.84 MPa. During this process, heat is transferred from the air such that the temperature inside the cylinder remains constant. Calculate the work input (in kJ) during this process.
Answer:
Work input W = -200.39 KJ
Explanation:
From the question, we are given;
m = 1.15 kg
Constant temperature T1 = T2 = 27 + 273 = 300k
Since the temperature is constant, we can say that the process is isothermal
P1 = 111 KPa
P2 = 0.84 MPa = 0.84 * 1000 KPa = 840 KPa
Now what we want to calculate is W1-2
Mathematically, for isothermal process;
W1-2 = mRTlnP1/P2
where R can be obtained from table and it is equal to 0.287 KJ/kg.k
Hence;
W1-2 = (1.15)(0.287)(300)(ln 111/840)
W1-2 = 99.015 * -2.023871690525 = -200.39 KJ
Kindly note that the value of the work is negative because work is done on the system and not by the system
Two men, Joel and Jerry, each pushes an object that are identical on a horizontal frictionless floor starting from rest. Joel and Jerry are using the same force F. Jerry stops after 10 min, while Joel is able to push for 5.0 min longer. Compare the work they do.
Answer:
The work done by Joel is greater than the work done by Jerry.
Explanation:
Let suppose that forces are parallel or antiparallel to the direction of motion. Given that Joel and Jerry exert constant forces on the object, the definition of work can be simplified as:
[tex]W = F\cdot \Delta s[/tex]
Where:
[tex]W[/tex] - Work, measured in joules.
[tex]F[/tex] - Force exerted on the object, measured in newtons.
[tex]\Delta s[/tex] - Travelled distance by the object, measured in meters.
During the first 10 minutes, the net work exerted on the object is zero. That is:
[tex]W_{net} = W_{Joel} - W_{Jerry}[/tex]
[tex]W_{net} = F\cdot \Delta s - F\cdot \Delta s[/tex]
[tex]W_{net} = (F-F)\cdot \Delta s[/tex]
[tex]W_{net} = 0\cdot \Delta s[/tex]
[tex]W_{net} = 0\,J[/tex]
In exchange, the net work in the next 5 minutes is the work done by Joel on the object:
[tex]W_{net} = W_{Joel}[/tex]
[tex]W_{net} = F\cdot \Delta s[/tex]
Hence, the work done by Joel is greater than the work done by Jerry.
Signal propagation in the nervous system can be modeled as
a) A resistor network.
b) A wave of electricity that travels down conducting tissue.
c) A series of RC circuits.
Answer:
c) A series of RC circuits.
You work for an advertising company and have been hired to place a blimp above a football stadium. The angle of elevation from a point directly under the goal post is 72° and the blimp will be directly above the 50 yard line. a. Which trigonometric ratio would you use to calculate how high the blimp will be above the 50 yard line? b. How high above the ground is the blimp? c. In order to be able to read the advertisement on the side of the blimp the highest the blimp can be is 150 feet. Will the fans be able to read the advertisement? If not, what possible angle of elevation could we use? d. What is the exact angle if the blimp is at 150 feet?
Answer:
a) tangent ; b) 153.88 yds ; c) No , less than or equal to 45° ; D) 45°
Explanation:
Given the following ;
From the triangle sketch :
Base length = 50 yards
Angle of elevation = 72°
a. Which trigonometric ratio would you use to calculate how high the blimp will be above the 50 yard line?
Using trigonometry :
The height of the blimp will be calculated using :
Tangent :
Tan θ = opposite / Adjacent
B.) How high above the ground is the blimp?
Using :
Tan θ = opposite / Adjacent
Θ = 72° ; adjacent = 52, opposite = height(h)
Tan 72° = h / 50
h = 3.0776835 * 50
h = 153.88 yds
C.) In order to be able to read the advertisement on the side of the blimp the highest the blimp can be is 150 feet. Will the fans be able to read the advertisement?
1 yard = 3 Feets
153.88 yards = 3 * 153.88
= 461.65 feets
No, because the height of the blimp is 461.65 Feets which is greater than 150 Feets.
To make viewing possible, the angle of elevation should be:
50 yards is equivalent to (3 * 50) = 150 feets
Max imum Height of blimp = 150 Feets
From pythagoras ;
Tanθ = 150 Feets / 150 Feets
Tanθ = 1
θ = tan^-1(1)
θ = 45°
To make viewing advertisement possible, angle of elevation should not exceed 45°
d.)If height of blimp is 150 Feets, then the exact angle of elevation will be 45°
The region of magnetic influence around either pole of a magnet is called the magnetic field. The magnetic field line points out from the south magnetic pole and in from the north magnetic pole. This statement is:
Answer:
This statement is not true
Explanation:
Because The normal magnetic field line points out from the north magnetic pole and in from the south magnetic pole.
Answer:
false
Explanation:
hope this helps :)
Fill in the blanks in the following statements:
1. A parsec is defined as the distance from the Sun which would result in a parallax of_____ arcsecond as seen from Earth when observed 6 months apart.
2. One parsecs is about_____light years.
3. The more distant a star, the_____its parallax.
4. The statement "we can measure stellar parallax for most stars in our galaxy" is_____.
5. The closest stars have parallaxes smaller than______arcsecond.
6. The first successful measurements of stellar parallax were made by______in year______for the star named.
7. Star Fred has parallax four times greater than star Bob. Star Fred is______times______then star Bob.
Answer:
Explanation:
1. A parsec is defined as the distance from the Sun which would result in a parallax of_TWO____ arcsecond as seen from Earth when observed 6 months apart.
2. One parsecs is about_3.3____light years
3. The more distant a star, the_LESS ____its parallax.
4. The statement "we can measure stellar parallax for most stars in our galaxy" is__TRUE .___.
5. The closest stars have parallaxes smaller than_.002 _____arcsecond.
6. The first successful measurements of stellar parallax were made by_Friedrich Bessel_____in year_1838_____for the star named.
7. Star Fred has parallax four times greater than star Bob. Star Fred is__4____times_nearer_____than star Bob.
What is the wavelength of the following waves?
Answer:
i. the wavelength is 7.2 m
ii. the wavelength is 2.4 m
Explanation:
the wavelength of a wave is from crest to crest or from trough to trough.
1. Chanice drives her scooter 7 kilometres north. She stops for lunch and then drives 5 kilometres east. What distance did she cover? What was her displacement?
Answer:
i. Distance covered is 12 kilometres.
ii. Her displacement is 8.6 kilometres.
Explanation:
Distance is a span of length between two points, while displacement is the distance moved in a specified direction. Distance is a scalar quantity, while displacement is a vector.
She drives 7 kilometres north, then 5 kilometres east later.
i. Distance covered = 5 + 7
= 12
Her distance covered is 12 kilometres.
ii. To determine her displacement, apply the Pythagoras rule to the sketch of her journey.
[tex]x^{2}[/tex] = [tex]5^{2}[/tex] + [tex]7^{2}[/tex]
= 25 + 49
= 74
x = [tex]\sqrt{74}[/tex]
= 8.6023
Thus, her displacement is 8.6 kilometres.
Which of the following object is in dynamic equilibrium?
Answer:
A car driving in a straight line 20 m/s
Explanation:
ayepecks silly
A river flows with a speed of 3km/h in still water. A man who can swim with a speed of 5km/h wishes to reach a point on the other bank just opposite to the starting point. In which direction should he put his strokes and how long will he take to cross the river of width 1.2km? Please try to provide a diagram and step by step explanation.
Answer:
Explanation:
Let the angle required be θ with direction opposite to current .
cos θ = 3 / 5
θ = 53° .
Resultant velocity towards the opposite side
= √ ( 5 ² - 3²)
= 4 km /h
distance covered = 1.2 km
time taken = 1.2 / 4 = .3 h
= 18 min .
can someone plz go help me answer my question? I have to ask twice bc no one answered it the first time. a figure skater can increase her spin rotation rate from an initial rate of 1.0 rev every 1.5s to a final rate of 2.5rev/s. If her initial moment of inertia was 4.6kgxm^2, what is her final moment of inertia?
Answer:
1.2 kg m²
Explanation:
Angular momentum is conserved:
L = L
Iω = Iω
(4.6 kg m²) (1.0 rev / 1.5 s) = I (2.5 rev/s)
I = 1.2 kg m²