Answer:
3N
Explanation:
The frictional force always acts directly opposite to the force of motion, that is it opposes motion. According to the Newton second law of motion:
Sum of horizontal forces = 0
Hence:
5N - 4(0.5) - F = 0
5 - 2 = F
F = 3N
As an object’s speed decreases, its kinetic energy (KE) ________.
As an object’s height increases, its gravitational potential energy (PEg) ________.
What happens to most of the light waves that strike a clear pane of glass? O A. absorption B. diffraction O C. reflection O D. transmission
slight reflect but most goes through because glass is transparent
Most of the light waves that strike a clear pane of glass reflects. Details about reflection can be found below.
What is reflection?Refection in physics is the property of a propagated wave being thrown back from a surface such as a mirror.
Mirror is an example of an object that could be hit by an incumbent wave, however, most of the light waves that hit the mirror surface gets reflected back.
Therefore, most of the light waves that strike a clear pane of glass reflects.
Learn more about refection at: https://brainly.com/question/15487308
#SPJ2
A race car accelerates from 0 m/s to 30.0 m/s with a displacement of
45.0 m. What is the vehicle's acceleration?
1. O 2.00 m/s2
2. 5.00 m/s2
3. 15.0 m/s2
4. 10.0 m/s2
Answer:
4. 10.0 m/s²
Explanation:
I) if initial velocity is 'v₀', the final velocity is 'v', the accelaration is 'a', the distance is 'L' and elapsed time if 't', then:
[tex]1. \ a=\frac{v-v_0}{t};[/tex]
[tex]2. \ L=\frac{at^2}{2}.[/tex]
II) using these two equations after substitution v₀=0; v=30 and L=45:
[tex]\left \{{{45 =\frac{at^2}{2}} \atop {a=\frac{30-0}{t} }} \right.[/tex]
[tex]\left \{ {{at^2=90} \atop {at=30}} \right. \ <=> \ \left \{ {{a=10} \atop {t=3}} \right.[/tex] [tex]=> \ a=10\frac{m}{s^2}[/tex]
Which type of physical activity is being performed in the picture?
A.
cardiovascular
B.
strength training
C.
flexibility
D.
cross training
Reset Next
A bike travels at 20mph for 5 hours, then 10 mph for 3 hours. What is the average speed?
How do i solve for it?
Answer:
10 mph
Explanation:
please help me!!!!!!!!!!!!!!!
Answer:
3
Explanation:
i did it
g Calculate the electric potential at the center of the square with a side of 1 meter, formed by the four charged particles.
Answer:
The potential at the center of square due to four identical charges each at the corner is 5.09 q x [tex]10^1^0[/tex] Volts, where q is the charge.
Explanation:
From the question it is given that
side of square = a = 1 m
let the charge of each square is q
potential at center due to 1 charge is V = [tex]\frac{q}{4\pi \epsilon r}[/tex] , where
[tex]\epsilon[/tex] is electrical permittivity of space
r is the distance between charge and point.
since the charge is present at at the corner so the distance between charge and point is the half the length of diagonal of square.
⇒ distance between charge and point = r =[tex]\frac{a}{\sqrt{2}}[/tex] = [tex]\frac{1}{\sqrt{2} }[/tex] = 0.707 m
thus, V= [tex]\frac{q}{4\pi \epsilon r}[/tex] , on substituting the respected values of r = 0.707m and [tex]\frac{1}{4\pi \epsilon}[/tex] = 9 x [tex]10^9[/tex] we get,
V = 1.272 q x [tex]10^1^0[/tex] V
thus potential due to all 4 charges is
V = 1.272 q x [tex]10^1^0[/tex] x 4 = 5.09 q x [tex]10^1^0[/tex] Volts
the motion diagrams shown above represent cyclist 1 in the third panel above?
Answer:
A
Explanation:
Change of velocity is defined as acceleration and acceleration accounts for both change is direction and speed
A zone plate is found to give series of images of a point source on its axis. If the strongest and the second strongest images are at distances of 0.30m and 0.06 m respectively from the zone plate (both from the same side remote from the source), calculate the distance of the source from the zone plate, principal focal length and the radius of the second zone. Assume λ = 6 x 10-7m.
which is true about the way air flows
A. high pressure to low pressure
B. low pressure to high pressure
C. cold air to hot air
D. hot air to cold air
Answer:
A High-to-Low
Explanation:
its like water running down a hill.
A student drops a ball off the top of building and records that the ball takes 3.82s to reach the ground. Determine all unknowns and answer the following questions. Neglect drag.
What was the ball's speed just before striking the ground?
m/s
From what height was the ball dropped?
m
Explanation:
Given parameters:
Time of drop = 3.82s
Unknown:
Final velocity of the ball = ?
Height of fall = ?
Solution:
To solve this problem, we apply the appropriate motion equation.
To find the final velocity;
v = u + gt
v is the unknown final velocity
u is the initial velocity = 0m/s
g is the acceleration due to gravity = 9.8m/s²
t is the time
v = 0 + 9.8 x 3.82 = 37.4m/s
Height of drop;
H = ut + [tex]\frac{1}{2}[/tex]gt²
So;
H = (0 x 3.82) + ( [tex]\frac{1}{2}[/tex] x 9.8 x 3.82²) = 71.5m
The wavelength of a particular color of violet light is 417 nm. The energy of this wavelength of light is
Answer:
E = 4.7 x [tex]10^{-19}[/tex] Joules
Explanation:
Solution:
The wavelength of a particular color of violet light = 417 nm
What is the energy = ?
In order to calculate energy, we will use the following formula:
E = hf
where, f = frequency = 1/wavelength = c/λ
where c = speed of light = 299 792 458 m / s or 3 x [tex]10^{8}[/tex] m/s
where h = Plank's constant = 6.62x [tex]10^{-34}[/tex] [tex]m^{2}[/tex] kg / s
So,
λ = 417 nm
1 nm = [tex]10^{-9}[/tex] m
so,
λ = 417 x [tex]10^{-9}[/tex] m
Now, just plug in the values to calculate the energy of this wavelength of light.
E = hc/λ
E = ( 6.62x [tex]10^{-34}[/tex] ) (299 792 458) / (417 x [tex]10^{-9}[/tex] )
E = 0.047 x[tex]10^{-17}[/tex]
E = 4.7 x [tex]10^{-19}[/tex] Joules
You use 35 J of energy to move a 7.0N object.How far did it move
Answer:
5 metres
Explanation:
Work Done = Force x Distance
So Distance = Work done ÷ Force
= 35 ÷ 7.0
= 5 metres
a 45 kg boy sits on a horse on a carousel 5.0 m from the center of the circle. he makes a revolution every 8.0 s.
calculate his speed.
what is centripetal force acting on the boy?
For every complete revolution the boy makes around the center of the carousel, he travels a distance of 2π (5.0 m) = 10π m, which gives a linear speed of
v = (10π m) / (8.0 s) ≈ 3.927 m/s
Then his centripetal acceleration would be
a = v ² / (5.0 m) ≈ 3.084 m/s²
so that the centripetal force exerted on him has magnitude
F = (45 kg) a ≈ 138.791 N ≈ 140 N
(rounded to 2 significant digits)
Which process causes Earth to act like a magnet?
O A. Convection of hot material in the mantle
O B. Flow of water due to gravitational energy
O C. Movement of ions in the core
O D. Shifting of the tectonic plates
SUBMI
Answer:movement of iron in core
Explanatio
which of the following is not a mechanical form of energy?
a. Nuclear
b. Kinetic
c. Spring potential
d. Gravitational potential
Answer:
The answer is Spring Potential
Explanation:
Because all the others are a mechanical form of energy
A 0.323 kg ball is moving 13.9 m/s when it runs into a spring. If the spring compresses 0.350 m in bringing the ball to a stop, what is the spring constant?
Answer:
Explanation:
F = -k*x
k = F/x = (0.323*9.8)/(0.35)
k = 9.04
The kinetic energy of the spring is equal to its elastic potential energy. From this we can determine the force constant k. The force, constant of the ball here is 509.4 N/m.
What is spring constant ?The applied force f on an elastic material like a spring is directly proportional to the displacement x of the material.
Thus, f = -k x
here, the proportionality constant k is called spring constant or force constant. It can be defined as the force required to stretch or compress an elastic material by 1 m.
The elastic potential energy = 1/2 kx²
it is equal to the kinetic energy of the material if its move to form a wave like a spring.
Here, mass of the ball = 0.323 kg
velocity = 13.9 m/s
displacement = 0.350 m
then 1/2 mv² = 1/2 kx²
then k = mv²/x²
k = 0.323 kg × (13.9 m/s)²/ (0.35)² = 509.4 N/m
Therefore, the spring constant of the ball will be 509.4 N/m.
Find more on spring constant:
https://brainly.com/question/14973217
#SPJ2
A Nov-Dec power bill shows that a home uses 1355 kwh over a 30-day period. Find the energy used (in kJ) for the 30-day period.
Answer:
The energy used for the 30-day period is 4878000 kilojoules.
Explanation:
According to the power bill, 1355 kilowatt-hours was used over a 30-day period. A kilowatt-hour is equal to 3600 kilojoules. Then, we calculate the energy used, measured in kilojoules, is determined by simple rule of three:
[tex]E = 1355\,kWh\times \frac{3600\,kJ}{1\,kWh}[/tex]
[tex]E = 4878000\,kJ[/tex]
The energy used for the 30-day period is 4878000 kilojoules.
The wavelength of a particular color of yellow light is 579 nm. The energy of this wavelength of light is
Answer:
3.44× 10⁻¹⁹Joules
Explanation:
Energy of the wavelength is expressed using the formula:
E = hc/λ
h is the Planck constant
c is the velocity of light
λ is the wavelength
Given
h = 6.63 × 10^-34 m² kg / s
c = 3×10⁸ m/s
λ = 579nm = 579 × 10⁻⁹m
λ = 5.79× 10⁻⁷m
Substitute the given values into the formula
E = hc/λ
E = (6.63 × 10⁻³⁴× 3×10⁸)/5.79× 10⁻⁷
E = 19.89× 10⁻³⁴⁺⁸/5.79× 10⁻⁷
E = 19.89× 10⁻²⁶/5.79× 10⁻⁷
E = 3.44× 10⁻²⁶⁺⁷
E = 3.44× 10⁻¹⁹Joules
Hence the energy of this wavelength of light is 3.44× 10⁻¹⁹Joules
A gold wire that is 1.8 mm in diameter and 15 cm long carries a current of 260 mA. How many electrons per second pass a given cross section of the wire
Answer: 162500000
Explanation:
given data:
wire diameter = 1.8mm
wire length = 15cm
current = 260mA.
electron charge e = [tex]1.6*10^{-19} C[/tex]
Solution:
[tex]I = \frac{q}{t}[/tex]
where:
[tex]I = current\\\\q = charge\\\\t = time \\\\q=It\\\\q= 260mt[/tex]
[tex]q=ne\\\\n = \frac{q}{e} \\\\n= \frac{260*10^{-3} t}{1.6*10^{-19} } \\\\n= 162500000t\\\\\frac{n}{t} = 162500000[/tex]
number of electrons per seconds would be 162500000
Stand in a doorway so your toes and nose are against the doorway. 4. Grab a weight in each hand and hold your arms out from your body on either side of the wall. 5. Try to stand on your tip toes. What happens
Which two statements describe how ultrasound technology produces an
image of part of the body?
A. The amount of time it takes for a wave to return can be used to
create an image.
B. Low-frequency sound waves are reflected by tissues in the body.
C. High-frequency sound waves are reflected by tissues in the body.
D. Body tissues absorb high-frequency sound waves, producing an
image
Answer:
A,C
Explanation:
The amount of time it takes for a wave to return can be used to create an image
High--frequency sound waves are reflected by tissues in the body
Ultrasound technology produces an image of part of the body on: The amount of time it takes for a wave to return can be used to create an image and high-frequency sound waves are reflected by tissues in the body. So, option (A) and (C) is correct.
What is ultrasonic technology?Sound waves are used in ultrasound imaging to create images of the inside of the body. It aids in determining the origins of discomfort, edema, and infection in the body's internal organs as well as the examination of a developing fetus in pregnant women.
The same concepts underlie sonar used by ships, bats, and fisherman as well as those used by ultrasound imaging. A sound wave echoes or bounces back when it encounters an object. These echo waves can be measured to obtain information on the object's size, shape, and consistency as well as its distance from the source. Whether the thing is solid or liquid is included in this.
The amount of time it takes for a wave to return helps to create an image and high-frequency sound waves are reflected by tissues in the body. So, option (A) and (C) is correct.
To find more about ultrasonic, refer the link:
https://brainly.com/question/21336084
#SPJ5
How must a tennis serve start
Answer/Explanation:
When serving the primary serve, remain behind the benchmark between the middle imprint and the correct sideline. The ball is hit corner to corner into the administration box on the opposite side of the net, on the contrary side of the middle imprint from which the worker is serving.
Imagine you were lifting very heavy jugs to the top of a house. You can either use the stairs on the left or push them up the inclined plane on the right. Which option is easier
Answer:
Use the stairs
Explanation:
This is easier because if you go on the stairs you can rest if you get tired but if you go on the inclined plane then the weight of the jugs will make you slower than you already are and you may end up going back down instead of up where you wanna go.
This cantilever beam is loaded by two point loads. If the moment of inertia of the beam is 5.0*10-6 m4 and the modulus of elasticity is 210 GPa, the maximum deflection of the beam is:
Answer:
The answer is i just need the 5 pt sowwry bro hope you have luck finding it ;]
Explanation:
you prolly alr found it but it doesnt really matter
Select the correct answer.
Which of these factors will increase the speed of a sound wave in the air?
A. slowing down the movement of particles in the air
B. raising the temperature of the air
C. removing particles form the air
D. decreasing the kinetic energy of the air
E. stopping particle collisions in the air
Answer:
B
Explanation:
But molecules at a higher temperature have more energy.
Answer: B. Raising the temperature of the air
Sketch the electric field around these two objects if they have the same sign of charge. Make a separate drawing showing equipotential lines around the two charges. The potential is defined to be zero at infinity. Identify the line of zero potential between the two charges, if there is one.
Answer:
* far from one of the charges, the field of the other charge is small and can be neglected
* on the outside of the loads the fields are added territorially
* between the charges the two fields tend to vanish
Explanation:
The electric field around two objects with charge of the same sign, for simplicity suppose that the objects have positive point spherical charges,
E = k q / r2
bold letters indicate vectors, therefore the total electric field is
E_total = E1 + E2
the module of this field is
E_total = E1- E2
therefore we can outline this field
* far from one of the charges, the field of the other charge is small and can be neglected
* on the outside of the loads the fields are added territorially
* between the charges the two fields tend to vanish
An outline of these shows in Attachment A
The equipotential surfaces are defined as being perpendicular to the electric field lines since the electric field and the power difference are related
E = [tex]\frac{dV}{dx} i^ + \frac{dV}{dy} j^ + \frac{dV}{dz} k^ = \Delta V[/tex]
We can schematize some characteristics of these surfaces
* very close to each load are spherical surfaces
* very far from the load is an elliptical surface, which envelops the loads
* between them there is a point of zero potential point C
See attached part B
What is the speed of a commercial jet which travels form New York to Los Angeles (4800) in 6 hours
Answer:
[tex]Speed = 800km}/hr[/tex]
Explanation:
Given
[tex]Distance = 4800km[/tex]
[tex]Time = 6hr[/tex]
Required
Determine the speed of the jet
The speed is calculated as:
[tex]Speed = \frac{Distance}{Time}[/tex]
Substitute 4800 km for Distance and 6hr for Time
[tex]Speed = \frac{4800km}{6hr}[/tex]
[tex]Speed = 800km}/hr[/tex]
Hence, the speed of the commercial jet is 800km/hr
If a ball with a momentum of 40 kgm/s has a velocity of 2 m/s, what is its mass?
momentum (m)=40
velocity (v)=2
now,
momentum (m)=m×v
40=m×2
m=40÷2
m=20kg
What must a scientist do in order to develop a testable hypothesis?
Answer:
Explanation:
Ask a question that can be answered by making observations.
Answer: (APE X) Determine whether experimental observations can provide evidence to support a conclusion
Explanation:
