Answer:
0.0127m
Explanation:
Using
Ym= (1)(633x10^-9m)(2m) / (0.1x10^-3m) = 0.0127m
Suppose a point charge is located at the center of a spherical surface. The electric field at the surface of the sphere and the total flux through the sphere are determined. Now the radius of the sphere is halved. What happens to the flux through the sphere and the magnitude of the electric field at the surface of the sphere
Answer:
The magnitude of flux remains the same, and the field increases.
Explanation:
This is because the number of field lines leaving the sphere remains constant and the electric field increases because the line density increases
A spherical shell has inner radius 1.5 m, outer radius 2.5 m, and mass 850 kg, distributed uniformly throughout the shell. What is the magnitude of the gravitational force exerted on the shell by a point mass particle of mass 2.0 kg a distance 1.0 m from the center
Answer:
The magnitude of the gravitational force is 4.53 * 10 ^-7 N
Explanation:
Given that the magnitude of the gravitational force is F = GMm/r²
mass M = 850 kg
mass m = 2.0 kg
distance d = 1.0 m , r = 0.5 m
F = GMm/r²
Gravitational Constant G = 6.67 × 10^-11 Newtons kg-2 m2.
F = (6.67 × 10^-11 * 850 * 2)/0.5²
F = 0.00000045356 N
F = 4.53 * 10 ^-7 N
A flat loop of wire consisting of a single turn of cross-sectional area 8.60 cm2 is perpendicular to a magnetic field that increases uniformly in magnitude from 0.500 T to 2.40 T in 1.02 s. What is the resulting induced current if the loop has a resistance of 2.80
Answer:
The induced current is [tex]I = 5.72*10^{-4 } \ A[/tex]
Explanation:
From the question we are told that
The cross-sectional area is [tex]A = 8.60 \ cm^2 = \frac{8.60 }{10000} = 8.60 *10^{-4} \ m[/tex]
The initial value of magnetic field is [tex]B_1 = 0.500 \ T[/tex]
The value of magnetic field at time t is [tex]B_f = 2.40 \ T[/tex]
The number of turns is N = 1
The time taken is [tex]dt[/tex]= 1.02 \ s
The resistance of the loop is [tex]R = 2.80\ \Omega[/tex]
Generally the induced emf is mathematically represented as
[tex]e = - \frac{d \phi}{dt }[/tex]
Where [tex]d \phi[/tex] is the change n the magnetic flux which is mathematically represented as
[tex]d \phi = N *A * d B[/tex]
Where [tex]dB[/tex] is the change in magnetic field which is mathematically represented as
[tex]d B = B_f - B_i[/tex]
substituting values
[tex]d B = 2.40 - 0.500[/tex]
[tex]d B = 1.9 \ T[/tex]
So
[tex]d \phi = 1 * 1.9 * 8.60 *10^{-4}[/tex]
[tex]d \phi = 1.63*10^{-3} \ T[/tex]
So
[tex]e = - \frac{1.63 *10^{-3}}{ 1.02 }[/tex]
[tex]e = - 1.60*10^{-3} \ V[/tex]
Here the negative only indicates that the emf is acting in opposite direction of the motion producing it so the magnitude of the emf is
[tex]e = 1.60*10^{-3} \ V[/tex]
Now the induced current is evaluated as follows
[tex]I = \frac{e}{R }[/tex]
substituting values
[tex]I = \frac{1.60 *10^{-3}}{2.80 }[/tex]
[tex]I = 5.72*10^{-4 } \ A[/tex]
A block and tackle having a velocity ratio of 5 is used to raise a load of 400N through a distance of 10m. If the work done against friction is 100J. Calculate 1. Efficiency of the machine 2. The effort applied
Answer:
Explanation:
Load will be moved by 4L when effort moves by distance L .
4L = 10 m ( given )
L = 2.5 m
work output = work input = 400 x 10 = 4000 J
work by friction = 100 J
net work output = 3900 J .
efficiency = net output of work / work input
= (3900 / 4000) x 100
= 97.5 %
2 )
work input = 4000 J
distance moved by effort = 2.5 m
If effort be F
F X 2.5 = 4000
F = 1600 N .
When a potential difference of 10 V is placed across a certain solid cylindrical resistor, the current through it is 2 A. If the diameter of this resistor is now tripled, the current will be
Answer:
The current will be 18 A
Explanation:
Given;
potential difference, V = 10 V
current between the resistor, I = 2 A
Apply ohm's law;
V = IR
R = V / I
R = 10 / 2
R = 5Ω
Resistance is given as;
[tex]R = \frac{\rho l}{A}[/tex]
where;
ρ is resistivity
l is length
A is area
[tex]R = \frac{\rho l}{A} \\\\R = \frac{\rho l}{\pi r^2} = \frac{\rho l}{\pi (\frac{d}{2}) ^2} = \frac{\rho l}{\pi (\frac{d^2}{4}) }\\\\R = \frac{4*\rho l}{\pi d^2} \\\\R = (\frac{4*\rho l}{\pi } )\frac{1}{d^2} \\\\R = (k)\frac{1}{d^2} \\\\k = Rd^2\\\\R_1d_1^2 = R_2d_2^2\\\\R_2 = \frac{R_1d_1^2}{d_2^2}[/tex]
When the diameter of the resistor is tripled
d₂ = 3d₁
[tex]R_2 = \frac{5*d_1^2}{(3d_1)^2} \\\\R_2 = \frac{5d_1^2}{9d_1^2} \\\\R_2 = 0.556 \ ohms[/tex]
The current is now calculated as;
Apply ohms law;
V = IR
I = V / R
I = 10 / 0.556
I = 17.99 A
I = 18 A
Therefore, the current will be 18 A
The magnetic field strength at the north pole of a 2.0-cmcm-diameter, 8-cmcm-long Alnico magnet is 0.10 TT. To produce the same field with a solenoid of the same size, carrying a current of 1.8 AA , how many turns of wire would you need
Answer:
The number of turns of wire needed is 3536 turns.
Explanation:
Given;
length of the wire, L = 8 cm = 0.08 m
magnetic field on the wire, B = 0.1 T
current in the wire, I = 1.8 A
The magnetic field produced by a solenoid is calculated as;
B = μ₀ n I
where;
n is the number of turns per length = N / L
μ₀ is permeability of free space = 4π x 10⁻⁷ N/A²
[tex]B = \frac{\mu_o N I}{L} \\\\N = \frac{BL}{\mu_o I} \\\\N = \frac{0.1 *0.08}{4\pi*10^{-7} *1.8} \\\\N = 3536.32 \ turns[/tex]
Therefore, the number of turns of wire needed is 3536 turns.
Following a collision between a large spacecraft and an asteroid, a copper disk of radius 28.0 m and thickness 1.20 m, at a temperature of 850°C, is floating in space, rotating about its axis with an angular speed of 20.0 rad/s. As the disk radiates infrared light, its temperature falls to 20.0°C. No external torque acts on the disk.
A) Find the change in kinetic energy of the disk.
B) Find the change in internal energy of the disk.
C) Find the amount of energy it radiates.
Answer:
A. 9.31 x10^10J
B. -8.47x10 ^ 12J
C. 8.38x 10^12J
Explanation:
See attached file pls
A disk of radius 25.0cm turns about an axis through the center. The pull on the string produces a linear acceleration a(t)=At on the ball The disk starts from rest and after 3 seconds, linear a(3)=1.80m/s2. Find A and then write an expression for the angular acceleration α(t).
Answer:
The value for A is A= 0.6
The angular acceleration is [tex]\alpha (t) = 2.4 \ t \ m/s^2[/tex]
Explanation:
From the question we are told that
The radius of the disk is [tex]r = 25.0 \ cm = 0.25 \ m[/tex]
The linear acceleration is [tex]a(t) = At[/tex]
At time [tex]t = 3 \ s[/tex]
[tex]a(3) = 1.80 \ m/s^2[/tex]
Generally angular acceleration is mathematically represented as
[tex]\alpha(t) = \frac{a(t)}{r}[/tex]
Now at t = 3 seconds
a(3) = A * 3
=> 1.80 = A * 3
=.> A = 0.6
So therefore
a(t) = 0.6 t
Now substituting this into formula for angular acceleration
[tex]\alpha (t) = \frac{0.6 t }{R}[/tex]
substituting for r
[tex]\alpha (t) = \frac{0.6 t }{0.25}[/tex]
[tex]\alpha (t) = 2.4 \ t \ m/s^2[/tex]
If a 140 lb. climber saved her potential energy as she descended from Mt. Everest (Elev. 29,029 ft) to Kathmandu (Elev. 4,600 ft), how long could she power her 0.4 watt flashlight
Answer: 3217.79 hours.
Explanation:
Given, A 140 lb. climber saved her potential energy as she descended from Mt. Everest (Elev. 29,029 ft) to Kathmandu (Elev. 4,600 ft).
Power = 0.4 watt
Mass of climber = 140 lb
= 140 x 0.4535 kg [∵ 1 lb= 0.4535 kg]
⇒ Mass of climber (m) = 63.50 kg
Let [tex]h_1=29,029\ ft= 8848.04\ m\ \ \ \ [ 1 ft=0.3048\ m ][/tex] and [tex]h_2= 4,600 ft = 1402.08\ m[/tex]
Now, Energy saved =[tex]mg(h_1-h_2)=(63.50)(9.8)(8848.04-1402.08)=4633620.91\ J[/tex]
[tex]\text{Power}=\dfrac{\text{energy}}{\text{time}}\\\\\Rightarrow 0.4=\dfrac{4633620.91}{\text{time}}\\\\\Rightarrow\ \text{time}=\dfrac{4633620.91}{0.4}\approx11584052.28\text{ seconds}\\\\=\dfrac{11584052.28}{3600}\text{ hours}\ \ \ [\text{1 hour = 3600 seconds}]\\\\=3217.79\text{ hours}[/tex]
Hence, she can power her 0.4 watt flashlight for 3217.79 hours.
Two uniform solid balls are rolling without slipping at a constant speed. Ball 1 has twice the diameter, half the mass, and one-third the speed of ball 2. The kinetic energy of ball 2 is 37.0 J.
Part A What is the kinetic energy of ball 1?
Express your answer with the appropriate units.
K7 = Value Units
Answer:
The kinetic energy of the ball 1 is 2.06 J
Explanation:
The kinetic energy of a rolling object K = 1/2Iω² + 1/2mv² where I is its rotational inertia, ω its angular speed, m its mass and v = its velocity of center of mass.
Let m₁, I₁, v₁, d₁ represent the mass, rotational inertia, speed and diameter of solid ball 1. and Let m₂, I₂, v₂, d₂ represent the mass, rotational inertia, speed and diameter of solid ball 2.
Since both objects are spheres, I =2/5mr²
Let r₁ = radius of ball 1 and r₂ = radius of ball 2. Since d₂ = 2d₁
⇒ 2r₂ = 4r₁ ⇒ r₂ = 2r₁
Now, the the kinetic energy of sphere 1 is
K₁ = 1/2I₁ω₁² + 1/2m₁v₁² ω₁ = v₁/r₁ which is the angular speed of solid ball 1.
K₁ = 1/2(2/5mr²)v₁²/r₁² + 1/2m₁v₁²
K₁ = 1/5m₁v₁² + 1/2m₁v₁²
K₁ = 7/10m₁v₁²
Also, the the kinetic energy of sphere 2 is
K₂ = 1/2I₂ω₂² + 1/2m₂v₂² ω₂ = v₂/r₂ which is the angular speed of solid ball 2.
K₂ = 1/2(2/5m₂r₂²)v₂²/r₂² + 1/2m₂v₂²
K₂ = 1/5m₂v₂² + 1/2m₂v₂²
K₂ = 7/10m₂v₂²
Now, m₁ = m₂/2 and v₁ = v₂/3
Substituting these into K₁, we have
K₁ = 7/10(m₂/2)(v₂/3)²
K₁ = 7/10 × 1/18m₂v₂²
K₁ = (1/18)(7/10m₂v₂²)
K₁ = K₂/18
K₂ = 37.0 J/18
K₂ = 2.06 J
So, the kinetic energy of the ball 1 is 2.06 J
What is the wave length if the distance from the central bright region to the sixth dark fringe is 1.9 cm . Answer in units of nm.
Complete Question
The complete question is shown on the first uploaded image
Answer:
The wavelength is [tex]\lambda = 622 nm[/tex]
Explanation:
From the question we are told that
The distance of the slit to the screen is [tex]D = 5 \ m[/tex]
The order of the fringe is m = 6
The distance between the slit is [tex]d = 0.9 \ mm = 0.9 *10^{-3} \ m[/tex]
The fringe distance is [tex]Y = 1.9 \ cm = 0.019 \ m[/tex]
Generally the for a dark fringe the fringe distance is mathematically represented as
[tex]Y = \frac{[2m - 1 ] * \lambda * D }{2d}[/tex]
=> [tex]\lambda = \frac{Y * 2 * d }{[2*m - 1] * D}[/tex]
substituting values
=> [tex]\lambda = \frac{0.019 * 2 * 0.9*10^{-3} }{[2*6 - 1] * 5}[/tex]
=> [tex]\lambda = 6.22 *10^{-7} \ m[/tex]
[tex]\lambda = 622 nm[/tex]
A wire carries current in the plane of this screen toward the top of the screen. The wire experiences a magnetic force toward the right edge of the screen. Is the direction of the magnetic field causing this force
Answer:
The direction of the magnetic field causing this force is
In the plane of the screen and towards the bottom of the egde
Explanation:
This is by applying Fleming s right hand rule which explains that
When a conductor such as a wire attached to a circuit moves through a magnetic field, an electric current is induced in the wire due to Faraday's law of induction. The current in the wire can have two possible directions. Fleming's right-hand rule gives which direction the current flows.
The right hand is held with the thumb, index finger and middle finger mutually perpendicular to each other (at right angles), as shown in the diagram.[1]
The thumb is pointed in the direction of the motion of the conductor relative to the magnetic field.
The first finger is pointed in the direction of the magnetic field. (north to south)
Then the second finger represents the direction of the induced or generated current within the conductor (from the terminal with lower electric potential to the terminal with higher electric potential, as in a voltage source)
shows a mixing tank initially containing 2000 lb of liquid water. The tank is fitted with two inlet pipes, one delivering hot water at a mass flow rate of .8 lb/s and the other delivering cold water at a mass flow rate of 1.2 lb/s. Water exits through a single exit pipe at a mass flow rate of 2.5 lb/s. Determine the amount of water, in lb, in the tank after one hour
Answer:
the water that remain in the tank in one hour will be 200 lb
Explanation:
Initial mass of water in the tank = 2000 lb
hot water is delivered through the first inlet pipe at a rate of = 0.8 lb/s
cold water is delivered through the second inlet pipe at a rate of = 1.2 lb/s
exit pipe flow rate = 2.5 lb/s
amount of water in the tank after one hour = ?
In one hour, there are 60 x 60 seconds = 3600 sec, therefore
the water through the first inlet pipe in one hour = 0.8 x 3600 = 2880 lb
the water through the second inlet pipe in one hour = 1.2 x 3600 = 4320 lb
the water through the exit in one hour = 2.5 x 3600 = 9000 lb
The total amount of water in the tank = 2000 + 2880 + 4320 = 9200 lb
The total amount of water that leaves the tank = 9000 lb
therefore, in one hour, the water that remain in the tank will be
==> 9200 lb - 9000 lb = 200 lb
The index of refraction of a sugar solution in water is about 1.5, while the index of refraction of air is about 1. What is the critical angle for the total internal reflection of light traveling in a sugar solution surrounded by air
Answer:
The critical angle is [tex]i = 41.84 ^o[/tex]
Explanation:
From the question we are told that
The index of refraction of the sugar solution is [tex]n_s = 1.5[/tex]
The index of refraction of air is [tex]n_a = 1[/tex]
Generally from Snell's law
[tex]\frac{sin i }{sin r } = \frac{n_a }{n_s }[/tex]
Note that the angle of incidence in this case is equal to the critical angle
Now for total internal reflection the angle of reflection is [tex]r = 90^o[/tex]
So
[tex]\frac{sin i }{sin (90) } = \frac{1 }{1.5 }[/tex]
[tex]i = sin ^{-1} [\frac{ (sin (90)) * 1 }{1.5} ][/tex]
[tex]i = 41.84 ^o[/tex]
ransverse waves are sent along a 5.00-m-long string with a speed of 30.00 m/s. The string is under a tension of 10.00 N. What is the mass of the string
Answer:
0.055 kg
Explanation:
According to the given situation the solution of the mass of the string is shown below:-
Speed of the wave is
[tex]v = \sqrt{\frac{F_T\times Length\ of\ string}{Mass\ of\ string}}[/tex]
[tex]30.0 m/s = \sqrt{\frac{10 kg m/s^2\times 5.00 m}{Mass\ of\ string}[/tex]
Mass of string is
[tex]= \sqrt{\frac{10 kg m^2/s^2\times 5.00 m}{900 m^2 s^2}[/tex]
After solving the above equation we will get the result that is
= 0.055 kg
Therefore for calculating the mass of the string we simply applied the above formula.
A flat slab of material (nm = 2.2) is d = 0.45 m thick. A beam of light in air (na = 1) is incident on the material with an angle θa = 46 degrees with respect to the surface's normal.
Numerically, what is the displacement, D, of the beam when it exits the slab?
Answer:
Explanation:
Formula of lateral displacement
[tex]S_{lateral}=\frac{t}{cosr} \times sin(i-r)[/tex]
t is thickness of slab , i and r are angle of incidence and refraction respectively .
Given t = .45 m
sin i / sin r = 2.2
sin 46 / sin r = 2.2
sin r = .719 / 2.2 = .327
r = 19°
[tex]S_{lateral}=\frac{t}{cosr} \times sin(i-r)[/tex]
[tex]S_{lateral}=\frac{.45}{cos19} \times sin(46-19)[/tex]
= .45 x .454 / .9455
= .216 m
= 21.6 cm .
The displacement, D, of the beam when it exits the slab is; 21.65 cm.
We are given;
Refractive index of slab material; nm = 2.2
Thickness of slab; t = 0.45 m
Refractive index of air; na = 1
Angle of incidence; θa = 46°
From snell's law, we can calculate the angle of refraction from;
na × sin θa = nm × sin θm
Thus;
1 × sin 46 = 2.2 × sin θm
0.7193 = 2.2 × sin θm
sin θm = 0.7193/2.2
θm = sin^(-1) 0.32695
θm = 19.08°
Formula for the displacement of the beam is;
D = (t/cos θm) × sin (θa - θm)
Plugging in the relevant values gives;
D = (0.45/cos 19.08) × sin (46 - 19.08)
D = 0.4783 × 0.4527
D = 0.2165m = 21.65 cm
Read more at; https://brainly.com/question/24875145
If an object is placed at a distance of 10 cm in front of a concave mirror of focal length 4 cm, find the position and characteristics of the image formed. Also, find the magnification.
Answer:
Explanation:
Focal length f = - 4 cm
Object distance u = - 10 cm
v , image distance = ?
Mirror formula
[tex]\frac{1}{v} +\frac{1}{u} = \frac{1}{f}[/tex]
Putting the given values
[tex]\frac{1}{v} - \frac{1}{10} = - \frac{1}{4}[/tex]
[tex]\frac{1}{v}= - \frac{3}{20}[/tex]
v = - 6.67 cm .
magnification
m = v / u
= - 6.67 / - 10
= .667
so image will be smaller in size in comparison with size of object .
Characteristics will be that ,
1 ) it will be inverted and
2 ) it will be real image .
Two sound waves W1 and W2, of the same wavelength interfere destructively at point P. The waves originate from two in phase speakers. W1 travels 36m and W2 travels 24m before reaching point P. Which of the following values could be the wave length of the sound waves?
a. 24m
b. 12m
c. 6m
d. 4m
Answer:
a. 24 m
Explanation:
Destructive interference occurs when two waves arrive at a point, out of phase. In a completely destructive interference, the two waves cancel out, but in a partially destructive interference, they produce a wave with a time varying amplitude, but maintain a wavelength the wavelength of one of the original waves. Since the two waves does not undergo complete destructive interference, then the possible value of the new wave formed can only be 24 m, from the options given.
A car and a truck, starting from rest, have the same acceleration, but the truck accelerates for twice the length of time. Compared with the car, the truck will travel:_____.
a. twice as far.
b. one-half as far.
c. three times as far.
d. four times as far.
e. 1.4 times as far.
Answer:
d. four times as far
Explanation:
Initial velocity of car and truck, u = 0
let acceleration of both the truck and car = a
let the length of time for the acceleration = t
Let the time the truck accelerated = 2t
The distance traveled by the car is calculated as;
s = ut + ¹/₂at²
s₁ = 0(t) + ¹/₂at²
s₁ = ¹/₂at²
The distance traveled by the truck is calculated as;
s = ut + ¹/₂at²
s₂ = 0(2t) + ¹/₂a (2t)²
s₂ = ¹/₂a x 4t²
s₂ = 4 (¹/₂at²)
s₂ = 4(s₁)
Truck distance = four times car distance
Therefore, Compared with the car, the truck will travel four times as far
d. four times as far
A 2.0-cm length of wire centered on the origin carries a 20-A current directed in the positive y direction. Determine the magnetic field at the point x
A 2.0-cm length of wire centered on the origin carries a 20-A current directed in the positive y direction. Determine the magnetic field at the point x = 5.0m on the x-axis.
Answer:
1.6nT [in the negative z direction]
Explanation:
The magnetic field, B, due to a distance of finite value b, is given by;
B = (μ₀IL) / (4πb[tex]\sqrt{b^2 + L^2}[/tex]) -----------(i)
Where;
I = current on the wire
L = length of the wire
μ₀ = magnetic constant = 4π × 10⁻⁷ H/m
From the question,
I = 20A
L = 2.0cm = 0.02m
b = 5.0m
Substitute the necessary values into equation (i)
B = (4π × 10⁻⁷ x 20 x 0.02) / (4π x 5.0 [tex]\sqrt{5.0^2 + 0.02^2}[/tex])
B = (10⁻⁷ x 20 x 0.02) / (5.0 [tex]\sqrt{5.0^2 + 0.02^2}[/tex])
B = (10⁻⁷ x 20 x 0.02) / (5.0 [tex]\sqrt{25.0004}[/tex])
B = (10⁻⁷ x 20 x 0.02) / (25.0)
B = 1.6 x 10⁻⁹T
B = 1.6nT
Therefore, the magnetic field at the point x = 5.0m on the x-axis is 1.6nT.
PS: Since the current is directed in the positive y direction, from the right hand rule, the magnetic field is directed in the negative z-direction.
The primary of an ideal transformer has 100 turns and its secondary has 200 turns. If the input current at the primary is 100 A, we can expect the output current at the secondary to be
Answer:
Explanation:
For current in ideal transformer the formula is
I₁ / I₂ = N₂ / N₁
I₁ and I₂ are current in primary and secondary coil respectively and N₁ and N₂ are no of turns in primary and secondary coil .
Putting the given values
100 / I₂ = 200 / 100 = 2
I₂ = 50 A .
output current = 50 A .
An appliance with a 20.0-2 resistor has a power rating of 15.0 W. Find the maximum current which can flow safely through the appliance g
Q: An appliance with a 20 Ω resistor has a power rating of 15.0 W. Find the maximum current which can flow safely through the appliance g
Answer:
0.866 A
Explanation:
From the question,
P = I²R............................. Equation 1
Where P = power, I = maximum current, R = Resistance.
Make I the subject of the equation
I = √(P/R).................... Equation 2
Given: P = 15 W, R = 20 Ω
Substitute these values into equation 2
I = √(15/20)
I = √(0.75)
I = 0.866 A
Hence the maximum current that can flow safely through the appliance = 0.866 A
If radio waves were used to communicate with an alien spaceship approaching Earth at 10% of the speed of light c, Earth would receive their signals at a speed of
Answer:
Explanation:
speed of alien spaceship = .1 c
We shall apply formula of relativistic mechanics to solve the problem
relative velocity =
[tex]\frac{v+v_1}{1 -\frac{v\times v }{c^2} }[/tex]
Here v = v₁ = .1 c
relative velocity = .1c + .1 c / 1 - .1²
= .2 c / .99
= .202 c
The earth would receive the signal at the speed of .202 c .
PLEASE ANSWER FAST In which of the following situations is the greatest amount of work accomplished? 1. A boy lifts a 2-newton box 0.8 meters. 2. A boy lifts a 5-newton box 0.8 meters. 3.A boy lifts a 8-newton box 0.2 meters. 4.A boy lifts a 10-newton box 0.2 meters.
Explanation:
Work done is given by the product of force and displacement.
Case 1,
1. A boy lifts a 2-newton box 0.8 meters.
W = 2 N × 0.8 m = 1.6 J
2. A boy lifts a 5-newton box 0.8 meters.
W = 5 N × 0.8 m = 4 J
3. A boy lifts a 8-newton box 0.2 meters.
W = 8 N × 0.2 m = 1.6 J
4. A boy lifts a 10-newton box 0.2 meters.
W = 10 N × 0.2 m = 2 J
Out of the four options, in option (2) ''A boy lifts a 5-newton box 0.8 meters'', the work done is 4 J. Hence, the greatest work done is 4 J.
0.25-kg block oscillates on the end of a spring with a spring constant of 200 N/m. If the oscillations is started by elongating the spring 0.15 m and giving the block a speed of 3.0 m/s, then the maximum speed of the block is A :
Answer:
5.2m/s
Explanation:
Plss see attached file
The voltage across a membrane forming a cell wall is 72.7 mV and the membrane is 9.22 nm thick. What is the magnitude of the electric field strength? (The value is surprisingly large, but correct.) You may assume a uniform E-field.
Answer:
The magnitude of the electric field intensity is [tex]E = 7.89 *10^{6} \ V/m[/tex]
Explanation:
From the question we are told that
The voltage is [tex]\epsilon = 72.7 \ mV = 72.7 *10^{-3} V[/tex]
The thickness of the membrane is [tex]t = 9.22 \ nm = 9.22 *10^{-9} \ m[/tex]
Generally the electric field intensity is mathematically represented as
[tex]E = \frac{\epsilon }{t}[/tex]
substituting values
[tex]E = \frac{72.7 *10^{-3} }{9.22 *10^{-9}}[/tex]
[tex]E = 7.89 *10^{6} \ V/m[/tex]
A positively charged particle has a velocity in the negative z direction at a certain point P. The magnetic force on the particle at this point is in the negative y direction. Which one of the following statements about the magnetic field at point P can be determined from this data?
a. Bx is positive
b. Bz is positive
c. By is negative
d. By is positive
e. Bx is negative
Answer:
a. Bx is positive
Explanation:
See attached file
If 50 km thick crust having an average density of 3.0 g/cm3 has a surface elevation of 2.5 km above sea level, what would you predict about the surface elevation for 50 km thick crust with an average density of 2.8 g/cm3
Answer:
To calculate the predicted surface elevation of a 50km thick crust above a surface of 2.5km we are given a density of 3 gram per centimeter cube.
The displacement of the material will be calculated by subtracting the surface elevation of 2.5 km from the 50 km thick crust. Therefore 50-25= 47.5 km.
Thus let the density of the material be Pm
50*3= 47.5*Pm
Therefore: Pm= (50*3)/47.5= 3.16gram per centimeter cube
Thus with an average density of 2.8gram per centimeter cube
50*2.8= (50-x)*3.16
(50-x)= (50*2.8)/3.16
50-x=44.3
x=50-44.3= 5.7
Explanation:
To calculate the predicted surface elevation of a 50km thick crust above a surface of 2.5km we are given a density of 3 gram per centimeter cube.
The displacement of the material will be calculated by subtracting the surface elevation of 2.5 km from the 50 km thick crust. Therefore 50-25= 47.5 km.
Thus let the density of the material be Pm
50*3= 47.5*Pm
Therefore: Pm= (50*3)/47.5= 3.16gram per centimeter cube
Thus with an average density of 2.8gram per centimeter cube
50*2.8= (50-x)*3.16
(50-x)= (50*2.8)/3.16
50-x=44.3
x=50-44.3= 5.7
Question 8 of 10
On which parts of the heating curve for water does adding thermal energy
mainly cause the particles to move faster?
200
150 -
B
To
100
Temperature ('C)
A
50
С
0
-50
10
40
50
60
70
Time (min)
O A. C and D
B. A and B
O O O O
O C. Band C
OD. B and D
Answer:
The correct answer is A
Explanation:
In this exercise we are given a graph of temperature versus time.
In calorimeter processes there are two types
* one that when giving thermal energy to the system its temperature increases, this fundamentally due to the greater kinetic energy of the molecular ones, this process observes in the graphs as a straight line of constant slope
* A process donates all the thermal energy that is introduced is cracked in breaking the molecular bonds, taking matter from one thermodynamic state to another, for example: liquid to gas.
This process in curves as a horizontal line, that is, there is no temperature change,
When analyzing the graph shown, parts C and D are the one that show a change in temperature with thermal energy. The correct answer is A
Answer:
C and D
Explanation:
Just took the quiz
Two large non-conducting plates of surface area A = 0.25 m 2 carry equal but opposite charges What is the energy density of the electric field between the two plates?
Answer:
5.1*10^3 J/m^3
Explanation:
Using E = q/A*eo
And
q =75*10^-6 C
A = 0.25
eo = 8.85*10^-12
Energy density = 1/2*eo*(E^2) = 1/2*eo*(q/A*eo)^2 = [q^2] / [2*(A^2)*eo]
= [(75*10^-6)^2] / [2*(0.25)^2*8.85*10^-12]
= 5.1*10^3 J/m^3