Answer:
Explanation:
When the path difference is equal to wave length or its integral multiple, constructive interference occurs . If it is odd multiple of half wave length , then destructive interference occurs.
For constructive interference , path diff = n λ
For destructive interference path diff = ( 2n+ 1 ) λ /2
where λ is wave length of wave , n is an integer.
a )
path diff = 10 cm which is half the wavelength , so maximum destructive interference will occur.
b )
path diff = 15 cm which is neither half the wavelength nor full wavelength , so in between is the right option.
c )
path diff = 20 cm which is equal to the wavelength , so maximum constructive interference will occur.
d)
path diff = 30 cm which is 3 times half the wavelength , so maximum destructive interference will occur.
e)
path diff = 35 cm which is neither integral multiple of half the wavelength , nor integral multiple of wavelength so in between is th eright answer.
f )
path diff = 40 cm which is 2 times the wavelength , so maximum constructive interference will occur
A block of mass M is connected by a string and pulley to a hanging mass m. The coefficient of kinetic friction between block M and the table is 0.2, and also, M = 20 kg, m = 10 kg. How far will block m drop in the first seconds after the system is released?
How long will block M move during above time?
At the time, calculate the velocity of block M
Find out the deceleration of the block M, if the connected string is
removal by cutting after the first second. Then, calculate the time
taken to contact block M and pulley.
Answer:
a) y = 0.98 t², t=1s y= 0.98 m,
b) he two blocks must move the same distance
c) v = 1.96 m / s, d) a = -1.96 m / s², e) x = 0.98 m
Explanation:
For this exercise we can use Newton's second law
Big Block
Y axis
N-W = 0
N = M g
X axis
T- fr = Ma
the friction force has the expression
fr = μ N
fr = μ Mg
small block
w- T = m a
we write the system of equations
T - fr = M a
mg - T = m a
we add and resolved
mg- μ Mg = (M + m) a
a = [tex]g \ \frac{m - \mu M}{m+M}[/tex]
a = [tex]9.8 \ \frac{10- 0.2 \ 20}{ 10 \ +\ 20}[/tex]
a = 9.8 (6/30)
a = 1.96 m / s²
a) now we can use the kinematic relations
y = v₀ t + ½ a t²
the blocks come out of rest so their initial velocity is zero
y = ½ a t²
y = ½ 1.96 t²
y = 0.98 t²
for t = 1s y = 0.98 m
t = 2s y = 1.96 m
b) Time is a scale that is the same for the entire system, the question should be oriented to how far the big block will move.
As the curda is in tension the two blocks must move the same distance
c) the velocity of the block M
v = vo + a t
v = 0 + 1.96 t
for t = 1 s v = 1.96 m / s
t = 2 s v = 3.92 m / s
d) the deceleration if the chain is cut
when removing the chain the tension becomes zero
-fr = M a
- μ M g = M a
a = - μ g
a = - 0.2 9.8
a = -1.96 m / s²
e) the distance to stop the block is
v² = vo² - 2 a x
0 = vo² - 2a x
x = vo² / 2a
x = 1.96² / 2 1.96
x = 0.98 m
the time to travel this distance is
v = vo - a t
t = vo / a
t = 1.96 /1.96
t = 1 s
What best describes a societal law
Answer:
Societal laws are based on the behavior and conduct made by society or government.hope it helps.stay safe healthy and happy.1. A message signal m(t) has a bandwidth of 5kHz and a peak magnitude of 2V. Estimate the bandwidth of the signal u(t) obtained when m(t) frequency modulates a carrier with a) kf = 10 Hz/V, b) kf = 100 Hz/V, and c) kf = 1000 Hz/V.
Answer:
3v at 5.3 herts
Explanation:
A body starts from rest and accelerates uniformly at 5m/s. Calculate the time taken by the body to cover a distance of 1km
Answer:
20 seconds
Explanation:
We are given 2 givens in the first statement
v0=0 and a=5
And we are trying to find time needed to cover 1km or 1000m.
So we use
x-x0=v0t+1/2at²
Plug in givens
1000=0+2.5t²
solve for t
t²=400
t=20s
In the late 19th century, great interest was directed toward the study of electrical discharges in gases and the nature of so-called cathode rays. One remarkable series of experiments with cathode rays, conducted by J. J. Thomson around 1897, led to the discovery of the electron.
With the idea that cathode rays were charged particles, Thomson used a cathode-ray tube to measure the ratio of charge to mass, q/m, of these particles, repeating the measurements with different cathode materials and different residual gases in the tube.
Part A
What is the most significant conclusion that Thomson was able to draw from his measurements?
He found a different value of q/m for different cathode materials.
He found the same value of q/m for different cathode materials.
From measurements of q/m he was able to calculate the charge of an electron.
From measurements of q/m he was able to calculate the mass of an electron.
Part B
What is the distance Δy between the two points that you observe? Assume that the plates have length d, and use e and m for the charge and the mass of the electrons, respectively.
Express your answer in terms of e, m, d, v0, L, and E0.
Part C
Now imagine that you place your entire apparatus inside a region of magnetic field of magnitude B0 (Figure 2) . The magnetic field is perpendicular to E⃗ 0 and directed straight into the plane of the figure. You adjust the value of B0 so that no deflection is observed on the screen.
What is the speed v0 of the electrons in this case?
Express your answer in terms of E0 and B0.
Answer:
a) He found the same value of q/m for different cathode materials.
b) y = [tex]- \frac{e}{m}\ \frac{E_o v_o^2 }{2d^2}[/tex] , c) v = [tex]\frac{E_o}{B_o}[/tex]
Explanation:
In Thomson's experiments he was able to measure the deflection of the light beam under the effect of the magnetic field and with these results find the e / m relationship, which in all cases is the same, therefore the most important conclusion is that the value e E / m is constant for all materials.
b) In the part of the plates the electrons are accelerated by the electric field,
F = ma
- e E = m a
a = - (e/m) E₀
the distance traveled is
X axis
x = v₀ t
the separation of the plates is x = d
t = vo / d
Y axis
y = v_{oy} t + ½ to t²
y = ½ a t²
y = [tex]- \frac{e}{m}\ \frac{E_o v_o^2 }{2d^2}[/tex]
c) In this case there is a magnetic field B₀ and the electrons have no deflection
F = - e E + e v x B
if there is no deviation F = 0
e E = e v B
v = [tex]\frac{E_o}{B_o}[/tex]
Think about a thermos bottle. It consists of an inner bottle with a shiny silver surface separated from an outer container by a space with no air. In what ways does it block conduction, convection, and radiation?
Answer:
Radiation
Explanation:
Conduction, convection and radiation are the three modes of heat transfer.
1. Conduction: When the one end is heated of any rod, the heat transfer to the other end by the vibrational motion of the molecules, it is called conduction.
The heat transfer in a solid is due to the conduction.
2. Convection: When the liquid or gas is heated, the molecules which is in contact to the heat, heated first and due to the decrease in density they moves up and the molecules on the upper side are higher in density so they moves down. These are called convection currents. The process continues till the entire liquid becomes heated. It generally takes place in liquids and gases.
3. Radiation: The process of heat transfer in which no molecules takes place is called radiation. The heat coming from sun is due to the radiation. It does not require any medium.
In the thermos bottle, as there is no air between the two layers, so the heat transfer is due to the radiation.
If 2cm³ of wood has a mass 0.6g what would be its density
we know density = mass/ volume
as mass = 0.6 g
and volume = 2cm³
so density = (6/20)(g/cm³)
0.3g/cm³ (ans)
Hope it helps
8. If a moving object triples its speed, how much kinetic energy will it have? A. six times as much as before B. three times as much as before C. one third as much as before D. nine times as much as before
D
Explanation:
KE: 0.5mv²
when v is tripled v² is 9 times its original value
The correct equation for the x component of a vector named A with an angle measured from the x axis would be which of the following?
Answer:
Acosθ
Explanation:
The x-component of a vector is defined as :
Magnitude * cosine of the angle
Maginitude * cosθ
The magnitude is represented as A
Hence, horizontal, x - component of the vector is :
Acosθ
Furthermore,
The y-component is taken as the sin of the of the angle multiplied by the magnitude
Vertical, y component : Asinθ
Why does a compass give unreliable readings when used near electrical appliances
Answer:
Explanation:
Since the compass uses a magnetic field, if anything else magnetic is near it, the compass will start acting up. Making it unreliable so keep magnets away!
lamp in a child's Halloween costume flashes based on an RC discharge of a capacitor through its resistance. The effective duration of the flash is 0.360 s, during which it produces an average 0.690 W from an average 3.00 V. (a) What energy does it dissipate
Energy = (power) x (time)
Energy = (0.69 W) x (0.36 sec)
Energy = 0.25 Joule
A
Fluids in which the shear stress must reach
certain minimum value(yield stress)
before flow commences are called
Answer:
Plastic
Explanation:
Shear Modulus can be defined as the ratio of shear stress to shear strain with respect to a physical object.
This ultimately implies that, Shear Modulus arises as a result of the application of a shear force on an object or body which eventually leads to its deformation. Thus, this phenomenon is simply used by scientists to measure or determine the rigidity of an object or body.
Fluids in which the shear stress must reach certain minimum value (yield stress) before flow commences are called plastic. Thus, a plastic would only begin to flow when its shear stress attain a certain minimum value (yield stress). The unit of measurement of yield stress is usually mega pascal (MPa).
a baseball is thrown vertically upward with an initial velocity of 20m/s.
A,what maximum height will it attain? B,what time will elapse before it strike the ground?
C,what is the velocity just before it strike the ground?
Answer:
Look at explanation
Explanation:
a)Only force acting on the object is gravity, so a=-g (consider up to be positive)
use: v^2=v0^2+2a(y-y0)
plug in givens, at max height v=0
0=400-19.6(H)
Solve for H
H= 20.41m
b) Use: y=y0+v0t+1/2at^2
Plug in givens
0=0+20t-4.9t^2
solve for t
t=4.08 seconds
c) v=v0+at
v=20-39.984= -19.984m/s
You have two identical beakers A and B. Each beaker is filled with water to the same height. Beaker B has a rock floating at the surface (like a pumice stone). Which beaker, with all its contents, weighs more. Or are they equal?
Answer:
a) if we assume that the water does not spill, Beaker B weighs more than beaker S, or which in this case Beaker A weighs more
b) If it is spilled in water the weight of the two beakers is the same
Explanation:
The beaker weight is
beaker A
W_total = W_ empty + W_water
Beaker B
W_total = W_ empty + W_water + W_roca
a) if we assume that the water does not spill, Beaker B weighs more than beaker S, or which in this case Beaker A weighs more
b) If it is spilled in water, the weight of the two beakers is the same because the amount of liquid spilled and equal to the weight of the stone, therefore the two beakers weigh the same
An electrostatic paint sprayer has a 0.100 m diameter metal sphere at a potential of 30.0 kV that repels paint droplets onto a grounded object. (a) What charge (in C) is on the sphere?(b) What charge must a 0.100-mg drop of paint have to arrive at the object with a speed of 10.0 m/s?
Answer:
A) q = 1.67 × 10^(-7) C
B) q = 1.67 × 10^(-10) C
Explanation:
We are given;
Potential; V = 30 KV = 30000 V
Radius of sphere; r = diameter/2 = 0.1/2 = 0.05 m
A) To find the charge of the sphere, we will use the formula;
V = kq/r
Where;
q is the charge
k is electric force constant = 9 × 10^(9) N.m²/C²
Thus;
q = Vr/k
q = (30000 × 0.05)/(9 × 10^(9))
q = 1.67 × 10^(-7) C
B) Now, potential energy here is a formula; U = qV
However, for the drop of paint to move, the potential energy will be equal to the kinetic energy. Thus;
qV = ½mv²
q = mv²/2V
Where;
v is speed = 10 m/s
V = 30000 V
m = mass = 0.100 mg = 0.1 × 10^(-6) Thus;
q = (0.1 × 10^(-6) × 10²)/(2 × 30000)
q = 1.67 × 10^(-10) C
A ball on a frictionless plane is swung around in a circle at constant speed. The acceleration points in the same direction as the velocity vector.
a. True
b. False
Answer:
False
Explanation:
You have a circle so think back to circular motion. Theres 2 directions, centripetal and tangential. The problem tells you there's a constant tangential speed so tangential acceleration is 0. However there is a centripetal acceleration acting on the ball that holds it in its circular motion (i.e. tension, or gravity). Since centripetal is perpendicular to the tangential direction, acceleration and velocity are in different directions.
There are two beakers of water on the table. We can compare the average kinetic energy of the water molecules in the two beakers by measuring their
A temperatures.
B volumes.
C densities.
D masses.
Answer: masses
Explanation:
Trust me
A 1,200kg roller coaster car starts rolling up a slope at a speed of 15m/s. What is the highest point it could reach
Answer: 11.36 m
Explanation:
Given
Mass of roller coaster is m=1200 kg
Initial speed of roller coaster is v=15 m/s
Energy at bottom and at the top is same i.e.
[tex]\Rightarrow \dfrac{1}{2}mv^2=mgh\\\\\Rightarrow \dfrac{1}{2}\times 1200\times 15^2=1200\times 9.8\times h\\\\\Rightarrow h=\dfrac{15^2}{2\times 9.8}\\\\\Rightarrow h=11.36\ m[/tex]
Thus, the highest point reach by the roller coaster is 11.36 m
Answer:
11.36m
Explanation:
A simple pendulum takes 2.00 s to make one compete swing. If we now triple the length, how long will it take for one complete swing
Answer:
3.464 seconds.
Explanation:
We know that we can write the period (the time for a complete swing) of a pendulum as:
[tex]T = 2*\pi*\sqrt{\frac{L}{g} }[/tex]
Where:
[tex]\pi = 3.14[/tex]
L is the length of the pendulum
g is the gravitational acceleration:
g = 9.8m/s^2
We know that the original period is of 2.00 s, then:
T = 2.00s
We can solve that for L, the original length:
[tex]2.00s = 2*3.14*\sqrt{\frac{L}{9.8m/s^2} }\\\\\frac{2s}{2*3.14} = \sqrt{\frac{L}{9.8m/s^2}}\\\\(\frac{2s}{2*3.14})^2*9.8m/s^2 = L = 0.994m[/tex]
So if we triple the length of the pendulum, we will have:
L' = 3*0.994m = 2.982m
The new period will be:
[tex]T = 2*3.14*\sqrt{\frac{2.982m}{9.8 m/s^2} } = 3.464s[/tex]
The new period will be 3.464 seconds.
Al and Ben are on roller skates and Al rolls into Ben. Al exerts a force of 30 N on Ben when they
collide. Explain what force Ben exerts on AI.
Answer:
Reaction force
Explanation:
Newton´s 3rd law says that every force exerted in nature has an equal and opposite force.
For example here, when Al exerts force on Ben, Ben exerts the same amount of force (30N) on Al.
Al exerts the action force and Ben exerts the reaction force.
Need ur help,,, :-[ :-{
...... ............ .. ..
Answer:
Graph B express the magnetic relationship of magnetic flux and electronic flow
A football quarterback runs 15.0 m straight down the playing field in 3.00 s. He is then hit and pushed 3.00 m straight backward in 1.71 s. He breaks the tackle and runs straight forward another 24.0 m in 5.20 s. Calculate his average velocity (in m/s) for the entire motion. (Assume the quarterback's initial direction is positive. Indicate the direction with the sign of your answer.)
Answer:
Average Velocity = 3.63 m/s
Explanation:
First, we will calculate the total displacement of the quarterback, taking forward direction as positive:
Total Displacement = 15 m - 3 m + 24 m = 36 m
Now, we will calculate the total time taken for this displacement:
Total Time = 3 s + 1.71 s + 5.2 s = 9.91 s
Therefore, the average velocity will be:
[tex]Average\ Velocity = \frac{Total\ Displacement}{Total\ Time}\\\\Average\ Velocity = \frac{36\ m}{9.91\ s}[/tex]
Average Velocity = 3.63 m/s
A solenoid 10.0 cm in diameter and 85.1 cm long is made from copper wire of diameter 0.100 cm, with very thin insulation. The wire is wound onto a cardboard tube in a single layer, with adjacent turns touching each other. What power must be delivered to the solenoid if it is to produce a field of 8.90 mT at its center
Answer:
P = 29.3 W
Explanation:
The magnetic field in a solenoid is
B = μ₀ n i
i = B /μ₀ n
where n is the density of turns
We can use a direct rule of proportions or rule of three to find the number of turns, 1 a turn has a diameter of 0.100 cm = 10⁻³ m, in the length of
L= 85.1 cm = 0.851 m how many turns there are
#_threads = 0.851 / 10⁻³
#_threads = 8.50 10³ turns
the density of turns is
n = # _threads / L
n = 8.51 103 / 0.851
n = 104 turn / m
the current that must pass through the solenoid is
i = 8.90 10-3 / 4pi 10-7 104
i = 0.70823 A
now let's find the resistance of the copper wire
R = ρ L / A
the resistivity of copper is ρ = 1.72 10⁻⁸ Ω m
wire area
A = π r²
A = π (5 10⁻⁴)
A = 7,854 10⁻⁷ m²
let's find the length of wire to build the coil, the length of a turn is
Lo = 2π r = ππ d
Lo = π 0.100
Lo = 0.314159 m / turn
With a direct proportion rule we find the length of the wire to construct the 8.5 103 turns
L = Lo #_threads
L = 0.314159 8.50 10³
L = 2.67 10³ m
resistance is
R = 1.72 10⁻⁸ 2.67 10₃ / 7.854 10⁻⁷
R = 5,847 10¹
R = 58.47 ohm
The power to be supplied to the coil is
P = VI = R i²
P = 58.47 0.70823²
P = 29.3 W
The equations for calculating both the electric force and the gravitational force are above. Their equations are very similar. What is an important difference between these two forces?
A The electrical force is measured in coulombs; the gravitational force is measured in newtons.
B The electrical force between two charged objects will always be weaker than the gravitational force between them.
C The gravitational force decreases with the square of the distance between the objects; the electrical force increases with the square of the distance between the objects.
D Electrical forces can be attractions or repulsions; gravitational forces can only be attractions.
A, B, and C are hilarious. D is correct.
Charges can be positive or negative, so a pair of charges can be alike or opposite. But so far, we've never seen a negative mass.
The free-fall acceleration at the surface of planet 1 is 22 m/s^2. The radius and the mass of planet 2 are twice those of planet 1. What is the free-fall acceleration on planet 2?
Answer:
g₂ = 11 m/s²
Explanation:
The value of free-fall acceleration on the surface of a planet is given by the following formula:
[tex]g = \frac{Gm}{r^2}[/tex]
where,
g = free-fall acceleration
G = Universal Gravitational Constant
m = mass of the planet
r = radius of planet
FOR PLANET 1:
[tex]g_1 = \frac{Gm_1}{r_1^2}\\\\\frac{Gm_1}{r_1^2} = 22 m/s^2[/tex] --------------------- equation (1)
FOR PLANET 2:
[tex]g_2 = \frac{Gm_2}{r_2^2}\\\\g_2 = \frac{G(2m_1)}{(2r_1)^2}\\\\g_2 = \frac{1}{2}\frac{Gm_1}{r_1^2}\\\\[/tex]
using equation (1):
[tex]g_2 = \frac{g_1}{2}\\\\g_2 = \frac{22\ m/s^2}{2}[/tex]
g₂ = 11 m/s²
. Set the applied force to Force necessary to Keep the box Moving without accelerating. Restart the animation. Just before the box hits the wall, stop the animation. What can you tell me about relative magnitudes of the frictional force and the applied force
Answer:
elative magnitude of the two forces is the same and they are applied in a constant direction.
Explanation:
Newton's second law states that the sum of the forces is equal to the mass times the acceleration
∑ F = m a
in this case there are two forces on the x axis
F_applied - fr = 0
since they indicate that the velocity is constant, consequently
F_applied = fr
the relative magnitude of the two forces is the same and they are applied in a constant direction.
An inductor of inductance 0.02H and capacitor of capatance 2uF are connected in series to an a.c. source of frequency 200 Hz- Calculate the Impedance in the circuit . TC
Explanation:
Given:
L = 0.02 H
C = [tex]2\:\mu \text{F}[/tex]
f = 200 Hz
The general form of the impedance Z is given by
[tex]Z = \sqrt{R^2 + (X_L - X_C)^2}[/tex]
Since this is a purely inductive/capacitive circuit, R = 0 so Z reduces to
[tex]Z = \sqrt{(X_L - X_C)^2} = \sqrt{\left(\omega L - \dfrac{1}{\omega C} \right)^2}[/tex]
[tex]\:\:\:\:\:\:\:= \sqrt{\left(2 \pi L - \dfrac{1}{2 \pi f C} \right)^2}[/tex]
[tex]\:\:\:\:\:\:\:= \sqrt{\left[2 \pi (200\:\text{Hz})(0.02\:\text{H}) - \dfrac{1}{2 \pi (200\:\text{Hz})(2×10^{-6}\:\text{F})} \right]^2}[/tex]
[tex]\:\:\:\:\:\:\:= \sqrt{(25.13\:\text{ohms} - 397.89\:\text{ohms})^2}[/tex]
[tex]\:\:\:\:\:\:\:=372.66\:\text{ohms}[/tex]
how do you calculate voltage drop
Answer:
Multiply current in amperes by the length of the circuit in feet to get ampere-feet. Circuit length is the distance from the point of origin to the load end of the circuit.
Divide by 100.
Multiply by proper voltage drop value in tables. The result is voltage drop.
Explanation:
Determine the absolute pressure on the bottom of a swimming pool 27.0 m by 8.9 m whose uniform depth is 1.8 m . Express your answer using two significant figures.
Answer:
[tex]P=17658Pa[/tex]
Explanation:
From the question we are told that:
Dimension
[tex]L*B=27.0*8.9[/tex]
Depth [tex]d=1.8m[/tex]
Generally the equation for Volume of water is mathematically given by
[tex]V=L*B*D[/tex]
[tex]V=27.0*8.9*1.8[/tex]
[tex]V=432.54m^3[/tex]
Therefore
Force at the bottom of the Pool
[tex]F=\rho Vg[/tex]
Where
[tex]\rho \ density\ of \ water(1000kg/m^3)[/tex]
[tex]F=1000*432.54m^3*9.81[/tex]
[tex]F=4.2*10^{6}N[/tex]
Generally the equation for Pressure at the bottom is mathematically given by
[tex]P=\frac{Forece }{Area}[/tex]
[tex]P=\frac{4.2*10^{6}N}{27.0*8.9}[/tex]
[tex]P=17658Pa[/tex]
You are stranded in a stationary boat. Your friend is on a dock, but the boat is just beyond his reach. There is a 5 kg anchor in the boat. You'd like to get the boat to move closer to the dock so your friend can rescue you. Select from the following list what effect each change will have on the position of the boat relative to the dock. A. The boat will move closer to the dock. B. The boat will move away from the dock. C. The position of the boat relative to the dock will not change.
Answer:
running away and launching the anchor that will give a greater speed towards the dock v₄.
Explanation:
To try to bring the boat closer to the dock, several cases can be carried out.
* move inside the ship so that the center of mass changes and since moving away you have a speed v, the ship will approach the dock at a speed v₂,
* Throw the anchor in the opposite direction to the dock so that using the conservation of the moment the boat moves towards it, it moves at a speed v₃
* A combination of the two processes running away and launching the anchor that will give a greater speed towards the dock v₄.
In all cases, the friction must be zero.
All other movements move the ship away from the dock
