Answer:
v = 100 [km/h]
Explanation:
To solve this problem we must identify that the movement is at constant speed, that is, there is no acceleration, therefore we must use the following expression for Speed, which relates is displacement with time.
v = d/t
where:
v = velocity [km/h]
d = displacement = 70 [km]
t = time = 0.7 [h]
v = 70/0.7 = 100 [km/h]
28 points
An electric wall clock has a second hand 15 cm long. What is the radial acceleration of the tip of this hand?
A.4.25 x 10-4 m/s2
B.5.32 10-2 m/s2
C.1.64 x 10-3 m/s2
D.3.16 x 10-3 m/s2
Which of the following objects is in static equilibrium?
A. An apple falling from a tree
B. A car moving at a constant velocity
C. A motorcycle speeding up
D. A bicycle sitting on the ground
[tex]\longrightarrow \textsf{D. A bicycle sitting on the ground} [/tex]
Solution:-Let us check all options -
A) An apple falling from a tree is under the influence of gravity. Thus some force is acting on the apple and it can not said to be in state of equilibrium. B) A car moving at a constant velocity may said to be in state of equilibrium but the since the car is in motion ,equilibrium is dynamic in nature .Thus , it is not in static equilibrium.C) A motorcycle speeding up has some acceleration due to some forces. Thus it can also not be said in state of static equilibrium.D) Since the force acting on bicycle sitting down in zero as well as it is in state of rest , thus bicycle sitting on the ground may said to be in static equilibrium.what is the acceleration of the Tesla Model S in m/s²?
Answer: Tesla’s Model S Performance is the fastest-accelerating production car. The luxury sedan reaches 60 mph in just 2.4 seconds, which outperforms every supercar available today.
Explanation:
An 800 kg car exerts 4000N of applied force on a level road while
being opposed by 700 N of friction. Determine the acceleration of the car.
Answer:
a = 4.125 [m/s^2]
Explanation:
In order to calculate the value of acceleration, we must use Newton's second law, which tells us that the sum of forces must be equal to the product of mass by acceleration.
ΣF = m*a
where:
ΣF = sum of forces [N]
m = mass [kg]
a = acceleration [m/s^2]
Performing a summation of forces on the x-axis, we have:
4000 - 700 = m*a
4000 - 700 = 800*a
a = 4.125 [m/s^2]
The average speed of a runner in an 800 meter race was 7.0 meters per second.How long did it take the runner to complete the race?
Answer:
114.29s
Explanation:
average speed = distance/Time
Given
speed = 7m/s
distance = 800m
Required
Time taken by the runner to complete the race
From the formula:
Time = Distance/speed
Time = 800/7
Time = 114.29seconds
Hence it took the runner 114.29s to complete the race
Para levantar del suelo una caja metálica de 50 Kg se emplea maquinaria que utiliza un cable inextensible e imprime una aceleración de 0,8 m/seg2. ¿Qué tensión soporta el cable y qué tiempo le tomará a la máquina levantar la caja a una altura de 10 metros? Lo necesito urgente
Answer:
T = 530 N , t = 12.65 s
Explanation:
This is an exercise on Newton's second law,
T - W = m a
where T is the tension of the cable, W the weight and the steel of the box
T = W + ma
the weight of a body is
W = m g
Let's replace
T = m g + ma
T = m (g + a)
let's calculate
T = 50 (9.8 + 0.8)
T = 530 N
To calculate the time we use
y = v₀t + ½ a t²
since the box starts from rest on the sole its initial velocity is zero
y = ½ a t2
t = √ 2y / a
let's calculate
t = √ (2 10 / 0.8)
t = 12.65 s
TRASLATE
Este es un ejercicio de la segunda ley de Newton,
T – W = m a
donde T es la tension del cable, W el peso y a la aceracion de la caja
T = W + ma
el pesode un cuerpo es
W = m g
Substituyamos
T = m g + ma
T = m ( g +a)
calculemos
T = 50 ( 9,8 + 0,8)
T = 530 N
Para calcular el tiempo usamos
y = v₀t + ½ a t²
como la caja parte del reposo en el suela su velocidad inicial es cero
y= ½ a t²
t= √ 2y/a
calculemos
t = √ (2 10/0,8)
t = 12,65 s
Which zone shows the water table?
o 1
o 2
o 3
o 4
Answer:
3
Explanation:
i took the quiz
Fast food and juice boxes are example of which of these?
0 air pollution
0 water pollution
0 habitat destruction
0 overpackaging
Answer:
habitat destruction I think so
If you wanted to study regions where star formation is currently happening you could use: a. H-alpha emission to look for O and B stars b. 21 cm radiation to find neutral hydrogen clouds c. radio emission from carbon monoxide (CO) to find molecular cloud cores d. infrared emission to identify T Tauri stars
Whenever someone want to study regions where star formation is currently happening Infrared emission to identify T Tauri stars.
What is star-forming region?A star-forming region serves as a region of the celestial sphere where predominately young stellar objects can be found and where formation is likely occurring.
Infrared emission to identify T Tauri stars can be used in determining the formation, however it should be noted that Einstein X-ray Observatory made earliest detections of X-rays from T Tauri stars.
Learn more about star-forming region at;
https://brainly.com/question/25898149
29 HELP PLEASE!!! I'LL GIVE BEAINLIST!!!
Write a paragraph using eight words from the field of science. You can use the words listed.
words:
observation
hypothesis
theory
matter
agent
experimental group
control group
temperature
particle
criteria
Answer:
observation
hypothesis
theory
matter
agent
experimental group
control group
temperature
particle
criteria
Explanation:
how does a changing magnetic field affect a piece of copper wire?
Answer: When you change the direction of the current, you also change the direction of the magnetic field. Because the magnetic field created by the electric current in the wire is changing directions around the wire, it will repel both poles of the magnet by bending away from the wire.
Explanation:
Assertion : Human ear converts vibration with audible frequencies into electric signals. Reason : Audible sound lies in the range of 20 to 2000 Hz. *
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A)
Both assertion (A) and reason (R) are true but reason (R) is the not the correct explanation of assertion (A) Assertion (A) is true but reason (R) is false.
Assertion (A) is false but reason (R) is true.
Both Assertion and Reason is false
A car of mass 1500kg is brought to rest from a velocity of 25m/s by a constant force of 3,000N. Determine the change in momentum produced by the force and the time it takes for the car to come to rest.
answer:
change in momentum = 37,500kg.m/s in the opposite direction
time it takes = 12.5s
working:
u=25m/s
v=0m/s
F=ma
-3000=(1500)(a)
-3000÷1500=a
a= -2m/s^2
Change in momentum=mv-mu
(1500)(0)-(1500)(25)
= -37,500kg.m/s
relax the( - ) represents direction
v=u-at
0=25-2t
2t=25
t= 12.5s
A common flea is recorded to have jumped as high as 21 cm. Assuming that the jump is entirely in the vertical direction and that air resistance is insignificant, calculate the time it takes the flea to reach a height of 7.0 cm.
Answer:
t = 0.12 s
Explanation:
Applying the second equation of motion under free fall,
h = ut + [tex]\frac{1}{2}[/tex]g[tex]t^{2}[/tex]
where: h is the height, u is its initial velocity, t is the time taken and g is the gravitational force.
But, u = 0 m/s, h = 21 cm (0.21 m) and g = 9.8 m/[tex]s^{2}[/tex]. Then:
0.21 = 0 + [tex]\frac{1}{2}[/tex] x 9.8 x [tex]t^{2}[/tex]
0.21 = 4.9[tex]t^{2}[/tex]
[tex]t^{2}[/tex] = [tex]\frac{0.21}{4.9}[/tex]
= 0.04286
⇒ t = 0.2070
= 0.21 s
The time taken for the flea to jump as high as 21 cm is 0.21 s.
The time taken for the flea to reach a height of 7.0 cm (0.07 m) can be determined as;
h = ut + [tex]\frac{1}{2}[/tex]g[tex]t^{2}[/tex]
0.07 = 0 + [tex]\frac{1}{2}[/tex] x 9.8 x [tex]t^{2}[/tex]
0.07 = 4.9[tex]t^{2}[/tex]
[tex]t^{2}[/tex] = [tex]\frac{0.07}{4.9}[/tex]
= 0.01429
t = 0.1195
= 0.12 s
what is capacity and capacitor
Answer:
Explanation:
Capacity: the max amount that something can contain.
"the capacity of the freezer is 1.1 cubic feet"
capacitor: device for storing electrical energy, includes two conductor that are close to one another and insulated from each other. A simple example is a parallel-plate capacitor.
Source: Britannica.com
Answer:
capacitythe maximum amount that something can containcapacitora device used to store an electric charge, consisting of one or more pairs of conductors separated by an insulatorExplanation:
hope it helpslearn with brainlyAs light from a star spreads out and weakens, do gaps form between the photons?
Answer:
ggggggfjhfbgehfe no idk yes maybe
Explanation:
Why do tin roofs make creaking sounds on hot days?
Answer: Yes, on many slate-roofed homes as temperatures change, such as cooling at night or heating during the day, thermal expansion or contraction of the slates may cause movement that in turn causes snapping, popping, or cracking noises, even bangs and clanks or clicks from the roof.
Explanation:
Answer:
because of its mealting
Explanation:
hope it helps you
What is the value of the charge that experiences a force of 2.4 × 10–3 n in an electric field of 6.8 × 10–5 n/c? 1.6 × 10–7 c 2.5 × 10–3 c 2.8 × 10–3 c 3.5 × 101 c
The value of the charge will be 35 ×10¹ C. A charge is something experienced as a force in the electric and megnetic field.
what is the charge?When the matter is put in an electromagnetic field, it has an electric charge, which causes it to experience a force. A positive or negative electric charge can exist.
Charges that are similar repel each other, whereas charges that are dissimilar attract each other. The term "neutral" refers to an item that has no net charge.
The given data in the problem is;
F is the electric force= 2.4 × 10-³ N
q is the electric charge=?
E is the strength of the electric field = 6.8 × 10⁻⁵ (N/C)
The electric force is given by;
[tex]\rm F =qE \\\\ \rm q= \frac{F}{E} \\\\ \rm q= \frac{2.4 \times 10^{-3}}{6.8 \times 10^{-5}} \\\\ \rm q=35 \times 10^1 \ C[/tex]
Hence the value of the charge will be 35 ×10¹ C
To learn more about the charge refer to the link;
https://brainly.com/question/24391667
Answer:
D
Explanation:
E2020
4–15. The post is made of Douglas fir and has a diameter of 100 mm. If it is subjected to the load of 20 kN and the soil provides a frictional resistance that is distributed along its length and varies linearly from w = 4 kN>m at y = 0 to w = 12 kN>m at y = 2 m, determine the force F at its bottom needed for equilibrium. Also, what is the displacement of the top of the post A with respect to its bottom B? Neglect the weight of the post.
The image of the Douglas fir post is missing, so i have attached it.
Answer:
-0.00025918 mm
Explanation:
We are given the points it passes through as;
(y1, w1) = (0, 4)
(y2, w2) = (2, 12)
Thus, the slope is;
K = (w2 - w1)/(y2 - y1)
K = (12 - 4)/(2 - 0)
K = 8/2
K = 4
Now, substituting one of the points into the slope equation, we have;
w - w1 = k(y - y1)
w - 4 = 4(y - 0)
w = 4y + 4
For us to now find the total force the distributed load applies to the body, we will integrate to give;
W(y) = ∫w•dy
Thus;
W(y) = ∫(4y + 4)dy
W(y) = 2y² + 4y
So, the value of this force which is at y = 2 m will be;
W(2) = 2(2²) + 4(2)
W(2) = 16 KN
Now, at equilibrium, we sum up the forces in the vertical y-direction to give;
W - 20 + F = 0
F = 20 - W
F = 20 - 16
F = 4 KN
If we cut through the body to get a free body diagram and sum forces in y-direction to zero, the displacement of the top of the post A with respect to its bottom B is;
δ_B/A = [(L, 0∫)(W - 20)dy]/AE
Where A is πr²
We are given diameter = 100 mm
So, radius = 100/2 = 50 mm = 0.05 m
Also, from tables the Young's modulus of Douglas fir is 13.1 GPa or 13.1 × 10^(9) Pa
Thus;
δ_B/A = [(2, 0∫)(2y² + 4y - 20)dy]/(π × 0.05² × 13.1 × 10^(9))
δ_B/A = [((2 × 2³/3) + (2 × 2²) - 20(2)) - 0] /(0.102887 × 10^(9))
δ_B/A = (16/3 + 8 - 40)/(0.102887 × 10^(9))
δ_B/A = -0.00000025918 m = -0.00025918 mm
A machine has an efficiency of 60%. If the machine is required to overcome a load of 30N with a force of 20N, calculate its mechanical advantage?
Explanation:
eff = m.a/ v.r
m.a = L /E
30/ 20
= 1. 5
How is the final speed of the cart related to the pattern in the position data?
Answer:
it increases
Explanation:
The final speed of the cart increases in relation to the pattern in the position data.
What is speed?The rate at which an object moves along a path in time is defined as speed, whereas velocity is the rate and direction of movement.In other words, speed is a scalar value, whereas velocity is a vector. The symbol for velocity is v (italic), and the symbol for speed is v. (boldface). To represent average values, a bar is placed over the symbol.The ratio of an object's distance travelled (in any direction) to the time required to travel that distance. The rate at which the position of an object changes in any direction.The ratio of distance traveled to time spent traveling is defined as speed. Speed is a scalar quantity because it has only one direction and no magnitude.To learn more about velocity, refer to:
https://brainly.com/question/24445340
#SPJ2
CAN ANYONE PLS WRITE A POEM ABOUT NEON!!!!!!!!
Colors so bright
They catch your eye
You can see them from miles away
They shine in the night
Such beauty from dye
Oh so many ways they can array
litterly just got this off the top of my head. it was fun making.
A 100V battery is connected to two oppositely charged plates that are 10cm apart. i. What is the magnitude of the electric field? ii. Calculate the Electric Force exerted on a +200 C point charge. iii. What is the electric potential energy of the charge when it's 8cm and 2cm from the negatively charged plate? iv. How much work was required to move the charge from 8cm to 2cm? v. If the 10gram point charge was at rest at point A, what is the final speed at point B?
Answer:
1.) 1000 N/c
2.) 200000 N
3.) 60v
4.) 120000J
5.) 4899 m/s
Explanation:
Given that a 100V battery is connected to two oppositely charged plates that are 10cm apart.
1.) The magnitude of electric field strength is the ratio of potential difference per distance between the plates. That is,
Electric field = V/d
Electric field = 100/0.1
Electric field = 1000 wb
2.) Electric field strength is also the ratio of force per unit ccharge. That is,
Electric field = F / q
1000 = F / 200
Cross multiply
F = 1000 × 200
F = 200000 N
3.) What is the electric potential energy of the charge when it's 8cm and 2cm from the negatively charged plate?
The distance = 8cm - 2cm = 6cm
Electric field = V / d
Substitute the electric field and the distance into the formula
1000 = V / 0.06
Make V the subject of formula
V = 1000 × 0.06
V = 60 V
4.) How much work was required to move the charge from 8cm to 2cm?
Work done = VQ
Since V = 60v
Then,
Work done = 60 × 200
Work done = 120000 J
5.) If the 10 gram point charge was at rest at point A, what is the final speed at point B?
Work done = 1/2mv^2
120000 = 1/2 × 0.01 × v^2
V^2 = 120000/ 0.005
V^2 = 24000000
V = 4899 m/s
The magnitude of electric field strength has been 1000 wb.
The electric force (F) applied by 200 C charge has been 2000,000 N.
The values for electric potential energy has been 60 V.
The work done in moving the charge across the plate has been 12 kJ.
The speed of charge at point B has been 48.98 m/s.
The magnitude of electric field strength has been defined as the force per unit charge.
The expression for magnitude of electric field strength (E) has been:[tex]E=\dfrac{V}{d}[/tex]
Where, the voltage of battery, [tex]V=100\;\rm V[/tex]
The distance between plates, [tex]d=10\;\rm cm\;;0.1\;m[/tex]
Substituting the values for magnitude of electric field strength (E):
[tex]E=\dfrac{100}{0.1} \\E=1000\;\rm wb[/tex]
The magnitude of electric field strength has been 1000 wb.
The expression of electric force (F) applied by the battery has been given as:[tex]F=E\;\times\;q[/tex]
Where, the magnitude of electric field strength, [tex]E=1000\;\rm wb[/tex]
The charge for the force has been, [tex]q=200\;\rm C[/tex]
Substituting the values for electric force (F):
[tex]F=1000\;\times\;200\\F=200000\;\rm N[/tex]
The electric force (F) applied by 200 C charge has been 2000,000 N.
The electric potential energy (E) for charge has been given as:[tex]E=\dfrac{V}{d}[/tex]
The magnitude of electric field strength, [tex]E=1000\;\rm wb[/tex]
The distance between plates, [tex]d=8\rm \;cm-6\;cm\\d=2\;cm\;;0.02\;m[/tex]
Substituting the values for electric potential energy, (V):
[tex]1000=\dfrac{V}{0.0.06} \\V=1000\;\times\;0.06\\V=60\;\rm V[/tex]
The values for electric potential energy has been 60 V.
The work done (W) to move a charge has been given by:[tex]W=Vq[/tex]
Where, the electric potential energy of the battery has been, [tex]V=60\;\rm V[/tex]
The charge for the force has been, [tex]q=200\;\rm C[/tex]
Substituting the values for work done, (W):
[tex]W=60\;\times\;200\\W=12,000\;\text J\\W=12\;\rm kJ[/tex]
The work done in moving the charge across the plate has been 12 kJ.
The speed (v) of 10 g charge has been given as:[tex]W=\dfrac{1}{2}mv^2\\\\v=\sqrt{\dfrac{2W}{m} }[/tex]
Where, the work done on unit charge, [tex]W=12,000\;\rm J[/tex]
The mass of the charge, [tex]m=10\;g[/tex]
Substituting the values for calculating the speed of charge, (v):
[tex]v=\sqrt{\dfrac{2\;\times\;12,000}{10} } \\v=\sqrt{24,000}\\v=48.98\;\rm m/s[/tex]
The speed of charge at point B has been 48.98 m/s.
For more information about electric field, refer to the link:
https://brainly.com/question/12757739
why a body in uniform velocity is zero acceleration ?
what is illuminance
Answer:
The amount of luminous flux per unit area
Explanation:
The hair shaft is made up of three layers: an __ medulla , a cortex, and an ___cuticle
- absent; colored
-Colored; absent
-inner; outer
-outer ; inner
What is the acceleration of a mongoose that, if from rest, can reach
speeds of 19 ft/s in 8.8 seconds?
O 2.25 s
O 174.24 ft/s/s
2.25 ft/s/s
2.25 m/s
Explanation:
Acceleration is change in velocity over time.
a = Δv / Δt
a = (19 ft/s − 0 ft/s) / 8.8 s
a = 2.16 ft/s/s
Given parameters:
Initial velocity = 0m/s
Final velocity = 19ft/s
Time taken = 8.8s
Unknown:
Acceleration
Solution:
Acceleration is the change in velocity with time of a body;
Acceleration = [tex]\frac{v - u}{t}[/tex]
v is the final velocity
u is the initial velocity
t is the time taken
input the parameters and solve;
Acceleration = [tex]\frac{19 - 0}{8.8}[/tex] = 2.16ft/s
Now, the acceleration is 2.16ft/s
A portable hairdryer, plugged into a 110 V outlet, has a current of 10 A flowing through it. What is its power rating
Idris has a mass of 65 kg. He is standing on the second floor of his apartment building, 5 meters above the ground. What is his gravitational potential energy (GPE)? O A. 325J O B. 31,213 J O C. 3,185 J O D. 79.8J
Answer:A.325J
brainliest would be apreciated!
hope I helped!
A soccer ball is kicked at an angle of 40° from the ground at a speed of 30 m/s. 1. Describe which motion (horizontal of vertical) of the ball is constant and which is accelerated
2. What are the vertical and horizontal components of the ball's initial velocity? 3. For what length of time is the ball in the air assuming the ground is flat and horizontal?
4. What is the range of the ball assuming the ground is flat and horizontal?
Answer:
(1). This motion is projectile motion.
(2). The horizontal initial velocity is 19.3 m/s.
The vertical initial velocity is 22.9 m/s.
(3). The time is 3.9 sec.
(4). The range of the ball assuming the ground is flat and horizontal is 90.4 m.
Explanation:
Given that,
Angle = 40°
Velocity = 30 m/s
(1). A soccer ball is kicked at an angle from the ground at a speed of 30 m/s.
So, this motion will be projectile motion.
(2). We need to calculate the vertical and horizontal components of the initial velocity of the ball
Using formula of vertical initial velocity
[tex]u_{y}=u\cos\theta[/tex]
Put the value into the formula
[tex]u_{y}=30\cos40[/tex]
[tex]u_{y}=22.9\ m/s[/tex]
Horizontal initial velocity ,
[tex]u_{x}=u\sin\theta[/tex]
Put the value into the formula
[tex]u_{x}=30\sin40[/tex]
[tex]u_{x}=19.3\ m/s[/tex]
(3). We need to calculate the time
Using formula of time
[tex]t=\dfrac{2u\sin\theta}{g}[/tex]
Put the value into the formula
[tex]t=\dfrac{2\times19.3}{9.8}[/tex]
[tex]t=3.9\ sec[/tex]
(4). We need to calculate the range of the ball assuming the ground is flat and horizontal
Using formula of range
[tex]R=\dfrac{v^2\sin2\theta}{g}[/tex]
Put the value into the formula
[tex]R=\dfrac{30^2\sin80}{9.8}[/tex]
[tex]R=90.4\ m[/tex]
Hence, (1). This motion is projectile motion.
(2). The horizontal initial velocity is 19.3 m/s.
The vertical initial velocity is 22.9 m/s.
(3). The time is 3.9 sec.
(4). The range of the ball assuming the ground is flat and horizontal is 90.4 m.