Answer:
The velocity at that time would be [tex](-67.975\; \rm s)[/tex]. The velocity of this particle is continuously changing.
Explanation:
Differentiate the expression for position [tex]x[/tex] with respect to time [tex]t[/tex] to find an expression for velocity.
[tex]\begin{aligned}v(t) &= \frac{d}{dt}[x(t)] \\ &= \frac{d}{dt} \left[ 7.4 + 9.2\, t - 2.1\, t^{3}\right]\\ &= 9.2 - 6.3\, t^{2}\end{aligned}[/tex].
Hence, at [tex]t = 3.5\; \rm s[/tex], velocity would be [tex]v(3.5) = 9.2 - 6.3 \times (3.5)^{2} = -67.975\; \rm m[/tex].
Since velocity [tex]v(t)[/tex] changes with time [tex]t[/tex], the velocity of this particle is continuously changing.
If a car starts from rest and attains a velocity of 10m/square in 5 secondscalculate the accerleration
Explanation:
Acceleration = Velocity / Time
Acceleration = 10 / 5
Acceleration = 2m/s ²
What is the voltage of the power source if a motor with a resistance of 20 2 draws a
current of 1.5 A?
Answer:
190v I believe
hope this helped a little and if it did pls mark brainiest :)
when a .... cause an object to move through a ...., the .... on the object
Explanation:
velocity - the speed with a direction. Thus, inertia could be redefined as follows: Inertia: tendency of an object to resist changes in its velocity. ... Such an object will not change its state of motion (i.e., velocity) unless acted upon by an unbalanced force.
An athlete runs four laps of a 400 m track. What is the athlete's total displacement?
Answer:
○ 0 [tex]\checkmark[/tex]
Explanation:
Even if the athelete runs four laps of a 400 m track, its displacement will be 0 because the displacement is the shortest distance from its to final position. And, here the final and initial position is same since he comes to its initial position after covering certain distance. So, displacement is 0.
Two forces whose resultant is 100N are at right angle to eachother. if one of them makes an angle of 30° with the resultant, determine its magnitude
Let F₁ and F₂ denote the two forces, and R the resultant force.
F₁ and F₂ point perpendicularly to one another, so their dot product is
F₁ • F₂ = 0
We're given that one of these vectors, say F₁, makes an angle with R of 30°, so that
F₁ • R = ||F₁|| ||R|| cos(30°)
But we also have
F₁ • R = F₁ • (F₁ + F₂) = (F₁ • F₁) + (F₁ • F₂) = F₁ • F₁ = ||F₁||²
So, knowing that ||R|| = 100 N, we get that
(100 N) ||F₁|| cos(30°) = ||F₁||²
(100 N) cos(30°) = ||F₁||
||F₁|| ≈ 86.6 N
(And the same would be true for F₂.)
What unit is used in MKS system and FPS system
The "second" is the base unit of time in both systems.
Exercise b) 1) Fill in the blanks with the appropriate word: a) The pressure exerted by the air in atmosphere is called b) Pressure is the applied per unit area, c) The pressure ........as the depth of liquid increases. d) The SI unit of density is Az object fisats on water if the ...of the object is leva
Answer:
atmospheric pressure
b)
c)increases
d) ....
what you filling your heart with
oxygen and blood
Answer:
Explanation:
The right side of your heart receives oxygen-poor blood from your veins and pumps it to your lungs, where it picks up oxygen and gets rid of carbon dioxide. The left side of your heart receives oxygen-rich blood from your lungs and pumps it through your arteries to the rest of your body.
#I AM ILLITERATE
9. Which of the following is NOT a recommendation to help you succeed in this course?
Consistently and actively work in the course on a daily basis.
Wait until the end of the semester to complete all work.
Complete all assignments in a timely manner.
Contact your instructor if you have questions.
Answer:
Wait until the end of the semester to complete all work.
Explanation:
this is the obvious answer.
please mark me brainliest
Answer:
Wait until the end of the semester to complete all work
1.What is laser?
2.List the uses of laser in everyday life
Laser means Light Amplication by Stimulated Emission of Radiation.
Uses of laser
DNA sequencing instrument
Cutting and welding materials
Semiconducting chip manufacturing
Military devices
IF YOU LIKE MY ANSWER MARK AS BRAINLIEST
A cyclist goes round a circular path of circumference 343 m in s. The angle made by him, with the vertical is
WITH STEPS PLZ
you need the number of seconds to calculate the distance. I'm assuming that the seconds were written in the question but you forgot to write the here, you can calculate the distance then and find the exact point where the cyclist stopped since you have the circumference. then you can find the angle (after finding the distance he cycled) by subtracting it from 360 since the circular path will have an angle of 360 degrees.
Although your question lacks some data A general answer is provided :
The angle made vertically = 360° - x°
where x = angle at which the the cyclist stopped
and circumference of the circular path = Total Distance travelled by the cyclist
First step : determine the distance travelled by the cyclist vertically
circumference = 2*π*r
343 = 2*π * r
∴ r = 343 / ( 2π ) = 54.59
therefore distance travelled by the cyclist vertically = 54.59 * 2 = 109.18 m
Given that the time travelled is missing
assuming the angle to the distance travelled by the cyclist before it stopped vertically = 360° - x°
This is because the Total angle of a circular path = 360°
Learn more about circular paths : https://brainly.com/question/24210487
Potassium’s atomic number is 19, and its atomic mass is approximately 39. How many neutrons does potassium have?
19
58
20
39
Answer:
20
Explanation:
Atomic number is same as the number of protons of an atom and atomic mass is equal to the sum of number of protons and number of neutrons of an atom.
Atomic number = 19
So, number of protons (p) = 19
Atomic mass = 39
So, sum of number of neutrons and number of protons (n + p) = 39
Number of neutons (n)
= (n + p) - p
= 39 - 19
= 20
Potassium’s atomic number is 19, and its atomic mass is approximately 39, then Potassium would have 20 neutrons present inside its nucleus, therefore the correct answer is option C.
What is the atomic number?The total number of protons present in an atom is known as the atomic number of that atom. The atomic number has no correlation either with the number of neutrons or the number of electrons present inside an atom.
While the atomic mass of an atom is the sum of the total number of protons and the number of neutrons present inside of any atom.
atomic number= total number of protons
atomic mass = total number of protons + total number of the neutrons
As given in the problem Potassium’s atomic number is 19, this means Potassium has 19 protons
Potassium has an atomic mass of about 39
39 = total number of protons + total number of the neutrons
39 = 19 + total number of the neutrons
total number of the neutrons = 39-19
=20
Since potassium has an atomic mass of about 39 and an atomic number of 19, it would have 20 neutrons in its nucleus. Option C is the right response.
Learn more about the atomic number from here
brainly.com/question/14190064
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Suppose that people living near a particular​ high-voltage power line have a higher incidence of cancer than people living farther from the power line. Can you conclude that the​ high-voltage power line is the cause of the elevated cancer​ rate? If​ not, what other explanations might there be for​ it? What other types of research would you like to see before you conclude that​ high-voltage power lines cause​ cancer?
Complete Question
Complete Question is attached below
Answer:
a)Option B
b)Option B
Explanation:
a)
Without any confirmation it will be utterly wrong to conclude that high power voltage is the reason for the elevated cancer cases
Therefore
Option B
b)
The High Concentration of cells volume in a part of the Body is what causes Cancer
Therefore
Option B
D 2. Which of the following is an example of a specific goal?
O I want to lose weight.
I want to get stronger.
O I want to be able to walk one mile in 15 minutes.
I want to improve my speed.
I want to improve my speed
Answer:
D
Explanation:
why is the fuse used in a circuit called safety fuse?
Answer:
The maximum current which can flow through a fuse without melting it, is called its rating. ... If current higher than 8 A flows through the fuse, it would melt and circuit gets broken. ... Hence, fuse acts as a safety device
Answer:
The guy above me is right
Explanation:
Using a table for standard reduction potentials, calculate the minimum voltage needed to electrolyze potassium chloride into its elements (K(s) and Cl2(g)). Question 7 options: A) –1.57 V B) –4.29 V C) 1.57 V D) 4.29 V
Answer: B –4.29 V
Explanation:
I just took the quiz and I got a hundred percent make sure you pick B!!
Answer:
B –4.29 V ;)Explanation:
If the force on a spring is 1 N and it stretched 0.5 m, what is the spring
constant?
A.4 N/m
B.0.2 N/m
C.2 N/m
D. 0.4 N/m
We know
[tex]\boxed{\sf Spring\:constant(K)=\dfrac{F}{x}}[/tex]
[tex]\\ \sf\longmapsto K=\dfrac{1}{0.5}[/tex]
[tex]\\ \sf\longmapsto K=2N/m[/tex]
what are the examples of Inertia of motion
Seat belts tighten in a car when it stops quickly.
Men in space find it more difficult to stop moving because of a lack of gravity acting against them.
When playing football, a player is tackled, and his head hits the ground.
EXAMPLES ARE GIVEN BELOW:
HOPE IT'S HELPFUL FOR U MATE
I need help with this
Answer:
D, B, A, E, C
Explanation:
KE = m*g*h
PE = (1/2)m*v²
1. d
2. b
3. a
4. e
5. c
Classical mechanics (Forces) focuses on studying …
Electricity
Motion of Objects
Living Systems
Atomic Structure
Answer:
Motion of Objects
Explanation:
Motion of Objects
Both Static and Dynamic Forces.
4. When setting goals, you should do everything EXCEPT which of the following?
Take into account your current level of activity.
Ask all of your friends what they think your goals should be..
Set a time limit.
Be realistic.
if the radius of a coin is 1 cm then calculate its area.
Answer:
3.14*1²
3.14 cm²
I hope this will help
Answer:
3.14 cm squared
Explanation:
I hope this will help.
If a force of 1250 N acts on an area of 25 metres squared, what will be the pressure acting on the surface? Show your working as well.
Answer: 50 Pa
Explanation:
Pressure = Force/Area
Pressure = N/m^2
Pressure = 1250/25
Pressure = 50
Pressure = 50 Pa
please click thanks and mark brainliest if you like :)
Answer:
50 pascal
Explanation:
Force=1250N
Area=25m^2 [ pressure=force/area]
P=F/A
1250/25=50
What volume of silver metal will have a mass of exactly 2500.0 g? The density of silver is 10.50 g/cm3.
*Include your units!
Round your answer to the nearest tenth.
Explanation:
The density of silver is 10.5g/cm3
=2500.0g/10.5g/cm3
=238.09cm3
238.1cm3 to nearest tenth.
I hope my answer helps. Please mark as brainliest.
Which statement correctly compares the number of protons and electrons in atoms of rubidium (Rb) and calcium (Ca)?
(1 point)
Rubidium has fewer protons and fewer electrons than calcium.
Rubidium has fewer protons and more electrons than calcium.
Rubidium has more protons and fewer electrons than calcium.
Rubidium has more protons and more electrons than calcium.
Answer
#1. number of valence electrons
#2. oxygen
#3. Rubidium has more protons and more electrons than calcium.
#4. 20
#5. helium (he)
Explanation:
Answer:
Rubidium has more protons and more electrons than calcium.
Explanation:
for connexus honors chemistry unit 3 lesson 3 quick check :)
What is the symbol SI unit of time?
Answer:
second is the SI unit of time
Two difference between thrust and upthrust .
Upthrust is the upward force exerted by fluids on the surface of an object immersed in fluids. Thrust:- It is the force acting perpendicular to the surface. Upthrust:- It is the upward force exerted by the fluid on the surface of an object immersed in liquid.
I hope it's help you
1. Which of the following are good cross-training workouts for walking
Swimming
Biking
Basketball
All of the above
Answer:
All of the above is the answer
when an apple falls towards the earth the earth moves up to meet the apple. Is it true? If yes, why is the earth motion not noticeable ?
Answer:
Explanation:
The apple also exerts an equal and opposite force on the earth but earth does not move because the mass of apple is very small,due to which the gravitational force produces a large acceleration in it (a=F/m) and we can see the apple falling towards the earth but the mass of earth is very large,the same gravitational .
A car is moving with the velocity of 90km/h. If the car come to rest after 10 seconds. Calculate the final velocity and distance covered by the car within that time.
plz wirte the full formula
Answer:
you can learn from here
https://www.toppr.com/ask/en-bd/question/a-car-is-moving-with-a-velocity-of-10-ms-the-driver-sees-a-wall/
