Explanation:
The De-Broglie wavelength in terms of potential difference is given by:
[tex]\lambda=\dfrac{h}{\sqrt{2meV} }[/tex]
Where,
h is Planck's constant
m is mass of charged particle
V is potential difference
e is the amount of charge
It means that the De-Broglie wavelength is inversely proportional to the mass.
Since, the mass of the proton is more than the mass of the electron. So, the De- Broglie wavelength of the electron is larger than proton.
A spring with force constant of 59 N/m is compressed by 1.3 cm in a hockey game machine. The compressed spring is used to accelerate a small metal "puck" with mass 39.2 grams which will then slide up an inclined surface inside the machine. Assume friction is so tiny it may be ignored in this problem. How high in cm above its initial vertical position will the puck rise before stopping (momentarily at least)? Note: Convert units as necessary.
Answer:
The puck moves a vertical height of 2.6 cm before stopping
Explanation:
As the puck is accelerated by the spring, the kinetic energy of the puck equals the elastic potential energy of the spring.
So, 1/2mv² = 1/2kx² where m = mass of puck = 39.2 g = 0.0392 g, v = velocity of puck, k = spring constant = 59 N/m and x = compression of spring = 1.3 cm = 0.013 cm.
Now, since the puck has an initial velocity, v before it slides up the inclined surface, its loss in kinetic energy equals its gain in potential energy before it stops. So
1/2mv² = mgh where h = vertical height puck moves and g = acceleration due to gravity = 9.8 m/s².
Substituting the kinetic energy of the puck for the potential energy of the spring, we have
1/2kx² = mgh
h = kx²/2mg
= 59 N/m × (0.013 m)²/(0.0392 kg × 9.8 m/s²)
= 0.009971 Nm/0.38416 N
= 0.0259 m
= 2.59 cm
≅ 2.6 cm
So the puck moves a vertical height of 2.6 cm before stopping
how high off the ground is a a book that has 120 J of potential energy and a 4-kg mass
A rocket train car that is 30 m long is traveling from Los Angeles to New York at v=0.5c when a light at the center of the car flashes. When the light reaches the front of the car, it immediately rings a bell. Light reaching the back of the car immediately sounds a siren. A bicyclist waiting to cross the tracks sees the light in front of her at the instant when it flashes. Choose frame S' so that its origin is located at the center of the train. Take the direction of motion of the train (eastward) to be the positive direction of x'. Let the instant when the light flashes be t′=0s.
Required:
What are (x′A,t′A) and (x′B,t′B), the spacetime coordinates of event A and B in S'?
Answer: The reference frame of a passenger in a seat near the center of the train
Explanation:
the speed of light is the same for the passenger and the bicyclist
then the avents are simultaneous fo the passenger not for the bicyclist
the delay between the two events for the bicyclist is
Δt=Δd/vs
where
Δd= lenght of train
vs=speed of sound
the reference frame of a passenger in a seat near the center of the train
Solution:
The space and time transformations are:
x' = γ(x - vt)
t' = γ(t - vx/c²).
In the primed frame the two events are simultaneous, so that Δt' = 0. Also here Δx' = 30. In the unprimed frame Δx' = 30 = γ(Δx - v Δt).......(*)
We also have Δt' = 0 = γ(Δt - vΔx/c²)→Δx = c²Δt/v......(**)
Substituting (**) in (*): 30 = γ(c²Δt/v - vΔt))→Δt = 30/(c²/v - v) =
30/(2c - 0.5c) = 6.7 x 10^(-8)s
Kramer goes bowling and decides to employ the force of gravity to "pick up a spare." He rolls the 7.0-kg bowling ball very slowly so that it comes to rest a center-to-center distance of 0.25 m from the one remaining 1.5-kg bowling pin.
Required:
Determine the force of gravity between the ball and the pin and comment on the efficacy of the technique.
Answer:
[tex]1.12056\times 10^{-8}\ N[/tex].
Kramer could try blowing air on the bowling pin.
Explanation:
[tex]m_1[/tex] = Mass of bowling ball = 7 kg
[tex]m_2[/tex] = Mass of bowling pin = 1.5 kg
[tex]r[/tex] = Distance between them = 0.25 m
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²
Force of gravity is given by
[tex]F=\dfrac{Gm_1m_2}{r^2}\\\Rightarrow F=\dfrac{6.67\times 10^{-11}\times 7\times 1.5}{0.25^2}\\\Rightarrow F=1.12056\times 10^{-8}\ N[/tex]
The force of gravity between the ball and the pin is [tex]1.12056\times 10^{-8}\ N[/tex].
Kramer could try blowing air on the bowling pin.
How many significant figures does the number 0.0030 have?
A) 1
B) 2
C) 4
D) 3
While in a stream 39 cm deep, they look down into the water and see a craw fish at the bottom. How deep does the stream appear to the student? (nwater = 1.33)
Answer:
The depth of stream to the student is [tex]d_1 = 0.2932 \ m[/tex]
Explanation:
From the question we are told that
The actual depth of the stream is [tex]d = 39 \ cm = 0.39 \ m[/tex]
The refractive index of the water is [tex]n = 1.33[/tex]
Generally the apparent depth of the stream is mathematically represented as
[tex]d_1 = \frac{d}{1.33}[/tex]
substituting values
[tex]d_1 = \frac{ 0.39}{1.33}[/tex]
[tex]d_1 = 0.2932 \ m[/tex]
Maria was returning from her work when, when entering a street, she came across two unknown boys, who began to give praise to the girl:
_ You are the most beautiful girl seen in this world, said the first young man.
_ The moon is jealous of you! Said the second young man.
The girl went on her way and left.
What's wrong with this situation?
Answer:
Sexual harassment.
Explanation:
It is illegal to harass an individual on account of the sex of that person. sexual harassment includes inappropriate sexual advances, sexual favor demands, and other physical or verbal sexual misconduct. Nevertheless, harassment should necessarily not be of a sexual nature and may make derogatory comments about a person's sex. As per the question, it is unlawful to harass Maria by making offensive remarks and comments.
A car travelling at a constant speed of 70km/h passes a stationary police car. The police car immediately goes on the chase accelerating uniformly to reach a speed of 85km/h in 10s and continues at that speed until it overtakes the other car. Calculate the time taken for the police car to overtake the car?
Answer:
18.24 seconds
Explanation:
First you convert the km/h to m/s, 70km/h=(175/9)m/s,85km/h=(425/18)m/s.
You know it took 10 seconds for the police to reach 85 km/h. Calculate the distance that the car is ahead of the police (175/9)*10=1750/9m. Then by divide 1750/9 with 425/18, you will get the value 8.24. Add the 10 seconds with the 8.24 you will get 18.24 sec which is the total time.
A Georgia water worker accidentally strikes a water pipe with the end of his pickaxe while trying to dig a whole. If the pickaxe strikes with a force of 3,600N and the end of the pickaxe measures 15mm by 13mm, how much pressure is exerted on the pipe by the pickaxe
Answer:
Pressure, [tex]P=1.84\times 10^7\ Pa[/tex]
Explanation:
Given that,
Force with which pickaxe strikes is 3600 N
The end of the pickaxe measure 15mm by 13mm.
We need to find the pressure exerted on the pipe by the pickaxe. Pressure exerted is equal to the force acting per unit area. So,
[tex]P=\dfrac{F}{A}[/tex]
A = 15 mm × 13 mm = 195 mm² = 0.000195 m²
So,
[tex]P=\dfrac{3600\ N}{0.000195\ m^2}\\\\P=18461538.46\ Pa\\\\\text{or}\\\\P=1.84\times 10^7\ Pa[/tex]
So, the pressure of [tex]1.84\times 10^7\ Pa[/tex] is exerted on the pipe by the pickaxe.Calculate the momentum of at 1500 kg car traveling at 6 m/s?
Answer:
Explanation:
momentum =mass*speed
p=1500 kg*6 m/s
p=9000 kgm/s
It takes the Earth 24 hours to make a complete rotation around its axis. 33% Part (a) What is the period of rotation of the Earth in seconds? Grade Summary Deductions0 Potential 100 sin cotan) coso asin) atano acotan) sinh0 tan) acoso Attempts remaining per antemp4) detailed vie cosh0 tanhO cotanhO ODegrees O Radians Hint I give up Hints:-% deduction per hint. Hints remaining:- Feedback: dohction per fcedback ▲ 33% Part (b) What is the angular velocity of the Earth in rad/s? 33% Part (c) Given that Earth has a radius of 6.4 x 106 m at its equator, what is the linear velocity at Earth's surface?
Answer:
Explanation:
a )
one rotation per 24 hours
Time period of rotation of the earth T = time / no of rotation
T = 24 x 60 x 60 s / 1
= 86400 s .
b )
angular velocity = angle of rotation in radian / time
in one rotation , angle made at the centre = 2π radian
= 2 x 3.14 radian
angular velocity ω = 2π / T
= 2 x 3.14 / 86400 radian / s
= 72.68 x 10⁻⁶ radian / s
c )
Relation between linear and angular velocity is as follows
v = ω x R where R is radius of the earth and v is linear velocity .
linear velocity = 72.68 x 10⁻⁶ x 6.4 x 10⁶ m /s
= 465.152 m /s
=
If you push a 20-kg box with a net force of 10 N, what is the acceleration of the box? A) 20 m/s^2 B) 2 m/s^2 C) 0.5 m/s^2 INTEGRATED SCIENCE to the person who keeps deleting my questions ':(
Answer:
C) 0.5 m/s^2
Explanation:
[tex]Mass = 20kg\\Force = 10 N\\Acceleration = ?\\\\Force = Mass \times Acceleration \\\\Acceleration = \frac{Force}{Mass}\\\\ Acceleration = \frac{10}{20}\\ \\Acceleration = 1/2 = 0.5m/s^2[/tex]
the linear impulse and momentum equation is obtained by integrating the ______ with respect to time.
Answer:
and the forces acting on the particle as a function of time.
Explanation:
The principle of linear impulse and momentum is obtained by integrating the equation of motion with respect to time. hope this helps you :)
The linear impulse and momentum equation is obtained by integrating the force acting on the object with respect to time.
What is the linear impulse?The Linear Impulse is defined as the momentum exerted by a force during a time interval.
The linear impulse and momentum equation is obtained by integrating the force with respect to time.
From the equation of the impulse-momentum theorem:
∆p = J
where,
∆p is the change in momentum of the object,
J is the impulse applied to it.
The impulse is defined as the product of force and the time over which the force is applied.
Thus, we can write the impulse as:
J = ∫ F dt
where,
F is the force acting on the object,
dt is the time interval during which the force acts.
By substituting this expression for J in the momentum equation,
we get:
∆p = ∫ F dt
which is the linear impulse-momentum equation.
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You have a 100-kg object sitting on a frictionless tabletop. The object is connected to a spring with k = 1000 N/m and a natural length of 1 m with the other end of the spring connected to the wall. You pull the object 50 cm from the equilibrium position of the spring and hold it in place, and then release it.
Required:
a. How hard were you pulling on the object to hold it in place?
b. How much work did you do to move the object to that spot?
c. How close to the wall will the object get?
d. What is the fastest that the object moves and where is that location?
Answer:
a) 500 N
b) 250 J
c) 0.87 m
d) 1.58 m/s, at 0.6 m from the wall
Explanation:
The mass of the object m = 100 kg
the spring constant k = 1000 N/m
length of the the spring = 1 m
extension of the string = 50 cm = 0.5 m
a) Force used to pull the mass is gotten from Hooke's law equation
F = -kx
where F is the force used to pull = ?
k is the spring constant = 1000 N/m
x is the extension = 0.5 m
substituting, we have
F = 1000 x 0.5 = 500 N this force is used to pull the mass
b) The work done in moving the mass = Fx
==> 500 x 0.5 = 250 J
c) The energy stored up in the spring U = [tex]\frac{1}{2}kx^{2}[/tex]
U = [tex]\frac{1}{2}*1000*0.5^{2}[/tex] = 125 J
energy available for the mass from its equilibrium position = 250 - 125 = 125 J
this energy is equivalent to the work done by the spring on the mass by moving it closer to the wall
Work W = (weigh of the mass) x distance moved
weight = mg
where m is the mass = 100 kg
g is acceleration due to gravity = 9.81 m/s^2
substituting, we have
W = mgd
where d is the distance the mass moves closer to the wall
W = 100 x 9.81 x d
but W = 125 J
125 = 981d
d = 125/981 = 0.13 m
closeness to the wall = L - d
where L is the natural length of the spring = 1 m
closeness to the wall = 1 - 0.13 = 0.87 m
d) The maximum kinetic energy of the object will be halfway between the extended length and the final resting place.
extended length = 1 + 0.5 m = 1.5 m
distance from resting place = 1.5 - 0.87 = 0.63 m from the wall
At this point, all the mechanical energy on the mass and spring system is converted to kinetic energy of motion.
KE = [tex]\frac{1}{2}mv^{2}[/tex]
substituting,
125 = [tex]\frac{1}{2}*100*v^{2}[/tex] = [tex]50v^{2}[/tex]
[tex]v^{2}[/tex] = 125/50 = 2.5
v = [tex]\sqrt{2.5}[/tex] = 1.58 m/s
Why is it cooler to wear a white shirt than a black shirt on a hot, sunny day?
Answer:
because the colour black absorbs heat which will make you feel much hotter than a white shirt which blocks away heat.
What is the charge delivered by a current with an average of 0.54 A over 28.3 minutes?
Answer:
916.9C
Explanation:
Using Q= It
Q= 0.54A x 1698s
= 916.9C
The charge delivered by a current with an average of 0.54 A over 28.3 minutes is 916.9C.
What is Electric Charge?Electric charge is defined as the physical property of matter that causes that matter to experience a force when placed in an electromagnetic field that may be positive or negative such that charges repel each other and unlike charges attract each other. An object with the absence of net charge is said to be neutral.
The SI unit of electric charge is the coulomb which is a derived SI unit and is represented by the symbol C.
Electric Charge is represented as
Q= It
where, Q= Electric charge
I= Electric current
t= time
Q= 0.54A x 1698s
= 916.9C
Thus, the charge delivered by a current with an average of 0.54 A over 28.3 minutes is 916.9C.
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If you travel 5 miles north then turn and travel 5 miles south, you have traveled ______ miles
Answer: 10 miles
Explanation:
5 miles +5 miles= 10 miles (despite the directions)
This is the distance traveled
-------------------------------------
EXTRA STUFF ( you can literally ignore this part)
If you are asked for displacement instead for distance, then it will be 0 miles because you went 5 miles north and 5 miles south, which at the end, you are still at where you originally were.
Hope this helps!! :)
A sound source of frequency f moves with constant velocity (less than the speed of sound) through a medium that is at rest. A stationary observer hears a sound whose frequency is appreciably different from f because:________
a. interference effects set up a standing-wave pattern that alters the frequency
b. the wavelength established in the medium is not the same as it would be if the source were at rest.
c. the equation that relates velocity of propagation, frequency, and wavelength of a sound traveling through a medium does not apply in this situation
d. the sound wave travels through the medium with a velocity different from that which it would have if the source were at rest
Answer:
The correct answer is d
Explanation:
In this exercise they ask us which statement is correct, for this we plan the solution of the problem, this is a Doppler effect problem, it is the frequency change due to the relative speed between the emitter and the receiver of sound.
The expression for the Doppler effect of a moving source is
f ’= (v / (v- + v_s) f
From this expression we see that if the speed the sound source is different from zero feels a change in the frequency.
The correct answer is d
while you are in class, your iclicker falls off your desk to the floor. what forces are acting on your iclicker as it falls to the floor?
Answer:
Gravitational forces and drag forces
Explanation:
All objects that are above a certain distance above the ground has gravitational force acting on them. A falling body like the iclicker has gravitational force pulling it down with a magnitude proportional to its mass and the acceleration due to gravity. As the iclicker fall, it experiences air resistance due to the drag forces on it from the air molecules around. This drag force acts upwards so as to oppose the motion of the iclicker downwards, and the magnitude is minimal when compared to the gravitational force. The resultant force is therefore downwards
What is the direction of the electric field at a point a distance d = 34.00 cm directly to the right of the positive charge?
Answer:
s the charge is positive, the electric field lines leave it at the point a d = 0.034 cm, the electric field lines go to the right.
Explanation:
The electric field around the cagases oisitvi, field leaving this means that the field lines move away from
If the charge is negative the lines of the field are directed towards the charge
Let's apply this to our case, as the charge is positive, the electric field lines leave it at the point a d = 0.034 cm, the electric field lines go to the right.
The magnetic field inside a superconducting solenoid is 4.00 T. The solenoid has an inner diameter of 6.20 cm and a length of 26.0 cm.(a) Determine the magnetic energy density in the field.uB = 1 J / m3(b) Determine the energy stored in the magnetic field within the solenoid.UB = 2 kJ
Answer:
(a) The magnetic energy density in the field is 6.366 J/m³
(b) The energy stored in the magnetic field within the solenoid is 5 kJ
Explanation:
magnitude of magnetic field inside solenoid, B = 4 T
inner diameter of solenoid, d = 6.2 cm
inner radius of the solenoid, r = 3.1 cm = 0.031 m
length of solenoid, L = 26 cm = 0.26 m
(a) The magnetic energy density in the field is given by;
[tex]u _B = \frac{B^2}{2\mu_o} \\\\u _B = \frac{(4)^2}{2(4\pi*10^{-7})}\\\\u_B = 6.366*10^6 \ J/m^3[/tex]
(b) The energy stored in the magnetic field within the solenoid
[tex]U_B = u_B V\\\\U_B = u_B AL[/tex]
[tex]U_B = u_B(A)(L)\\\\U_B = 6.366*10^6(\pi * 0.031^2)(0.26) \\\\U_B = 4997.69 J\\\\U_B = 5 \ KJ\\[/tex]
A 40-turn coil has a diameter of 19 cm. The coil is placed in a spatially uniform magnetic field of magnitude 0.40 T so that the face of the coil and the magnetic field are perpendicular. Find the magnitude of the emf induced in the coil (in V) if the magnetic field is reduced to zero uniformly in the following times.
Complete Question
The complete question is shown on the first uploaded image
Answer:
a
[tex]\epsilon = 7.57 \ V[/tex]
b
[tex]\epsilon =0.0757 \ V[/tex]
c
[tex]\epsilon =0.00699 \ V[/tex]
Explanation:
From the question we are told that
The number of turns is N = 40 turns
The diameter is [tex]d = 19 \ cm = 0.19 \ m[/tex]
The initial magnetic field is [tex]B_i = 0.40 \ T[/tex]
The final magnetic field is [tex]B_f = 0 \ T[/tex]
Generally the cross-sectional area of the coil is mathematically represented as
[tex]A = \pi \frac{d^2}{4}[/tex]
=> [tex]A = 3.142 * \frac{0.19^2}{4}[/tex]
=> [tex]A = 0.0284 \ m^2[/tex]
At [tex]\delta t = 0.60 \ s[/tex]
The induced emf is
[tex]\epsilon = - N * \frac{[B_f - B_i ] * A }{\delta t }[/tex]
=> [tex]\epsilon = - 40 * \frac{[- 0.40 ] * 0.0284 }{0.06}[/tex]
=> [tex]\epsilon = 7.57 \ V[/tex]
At [tex]\delta t = 6 \ s[/tex]
The induced emf is
[tex]\epsilon = - N * \frac{[B_f - B_i ] * A }{\delta t }[/tex]
=> [tex]\epsilon = - 40 * \frac{[- 0.40 ] * 0.0284 }{6}[/tex]
=> [tex]\epsilon =0.0757 \ V[/tex]
At [tex]\delta t = 65 \ s[/tex]
The induced emf is
[tex]\epsilon = - N * \frac{[B_f - B_i ] * A }{\delta t }[/tex]
=> [tex]\epsilon = - 40 * \frac{[- 0.40 ] * 0.0284 }{65}[/tex]
=> [tex]\epsilon =0.00699 \ V[/tex]
A box at rest on a ramp at an incline of 22°. The normal force on the box is 538 N
Answer:
F = 580.25 N
Explanation:
It is given that,
A box at rest on a ramp at an incline of 22°
The normal force on the box is 538 N
We need to find the gravitational force on the box.
The force of gravity acting on an object is equal to its weight. So,
F = mg
But here the box is incline at an angle of 22 degrees
It means that mg will resolve in rectangular components such that, normal force is :
[tex]N=mg\cos\theta\\\\mg=F=\dfrac{N}{\cos\theta}\\\\F=\dfrac{538}{\cos22}\\\\F=580.25\ N[/tex]
So, the gravitational force on the box is 580.25 N.
A constant force of 5KN pulls a crate along a distance of 15 m in 75s.What is the power
Explanation:
We know,
1KN = 1000N
Then, Force(F) = 5*1000N
=5000N
Here,
Power (P)=Work(W)/Time(T)
=Force * distance/ Time (W = F*s)
= 5000*15/75
=1000
So, The power of body or object is 1000Watt.
I hope this will be helpful for you.
A coil has an inductance of 7.00 mH, and the current in it changes from 0.200 A to 1.50 A in a time interval of 0.250 s. Find the magnitude of the average induced emf in the coil during this time interval.
Answer:
Magnitude of the average induced emf = 36.4 mv
Explanation:
Given:
inductance of the coil (L) = 7 mH
Initial current (Ci) = 0.200 A
Final current (Cf) = 1.50 A
Interval = 0.250 s
Find:
Magnitude of the average induced emf
Computation:
E = L(di/dt)
E = 7 [(1.5-0.20) / 0.250]
E = 7[5.2]
Magnitude of the average induced emf = 36.4 mv
A yellow train of mass 100 kg is moving at 8 m/s toward an orange train of mass 200 kg traveling in the opposite direction on the same track at a speed of 1 m/s. What is the initial momentum of the orange train?.......... A. 200 kgm/s B. -200 kgm/s C. 100 kgm/s D. 80 kgm/s
Answer:The answer is option A.
Momentum=mass×velocity.
Orange train=mass is 200 and velocity is 1.
which is 200×1=200kgm/s.
The initial momentum of the orange train is 200 kgm/s.
What is momentum?Momentum is the product of mass and velocity of any object.Momentum is denoted by P.Momentum P = mv , where m = mass and v = velocity.Momentum is a vector quantity.How to calculate momentum of the orange train?
The orange train is having mass of 200 kg and it is travelling with speed of 1 m/s.
So, the orange trains momentum will be ,
P = mv
∴ P = 200 x 1
∴ P = 200 kgm/s
Therefore, the initial momentum of the orange train is 200kgm/s.
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What is the term for when the positive side of a battery is connected to the acceptor side and the negative side is connected to the donor side of the p-n rectifying junction?
Answer:
It is called Reverse biased
Explanation:
It is reverse bias because the voltage potential side of the battery is connected negative to the donor side or p type material and it is connected positive to the N type material or acceptor side across the diode which increases the diode width of the PN junction.
According to the Big Bang Theory, the density and temperature of the Universe is ___________ now than in the past.
Answer:
According to the Big Bang Theory, the density and temperature of the Universe is lower now than in the past.
Hope this answer correct :)
The density and the temperature of the universe should be lower as compared to the past.
What is the big bang theory?According to this theory, it description of the way the universe should be started is provided by the astronomers. The temperature of the universe should be very much hot, the universe size should be small also the universe should be super dense. However, the universe size should be expanded and the temperature should be colder according to the time.
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Give five difference between manometer and barometer
Answer:
Manometer is a measures to the atmospheric measure.
Barometer is a measure to the atmospheric pressure.
Explanation:
Manometer is there are two types (1) closed tube (2) open tube, is filled with liquid water and mercury and the tube.Manometer do not need equal size of the tubes to the open ended manometers.Manometers is simple to attach on this filled to the high pressure gas in the bulb,this gas pressure put on the tube.Manometer is the attach the gas and vacuum gas to the open of the air, its high pressure gas is to the one of end.Manometer are filled the mercury to the heavy liquid manometer filled the liquid water and oil with the mercury.Barometer is to the close ended tube and the glass tube is the open and that a vacuum is the other end.Barometer can the u shaped and the closed ended tubes to the barometers.Barometer is the mercury closed end and vacuum is the tallest point in the liquid.Barometer is also used to be a table or left standing and also be digital and portable traditional glass, may find the digital clock .Barometer are filled the mercury to the high level liquid must be extreme tall in change in atmospheric pressure.A ball is rolling down a hill. At one point near the top of the hill, it’s velocity is 2 m/s. Further down the hill, it’s velocity is 9 m/s what is tringlev?
Explanation:
The change in velocity is the final velocity minus the initial velocity.
Δv = v − v₀
Δv = 9 m/s − 2 m/s
Δv = 7 m/s