Questions
Find the distribution of temperature inside a sphere of radius a when the surface of the...

Find the distribution of temperature inside a sphere of radius a when the surface of the upper half is held at 100°C and the surface of the lower half at 0°C

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Describe the difference between an insulator and a conductor. What are some examples of each? Name...

Describe the difference between an insulator and a conductor. What are some examples of each? Name some examples when you would want to use each of them.

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John was swimming in the river. His swimming velocity was 1.2 m/s due east. The water...

John was swimming in the river. His swimming velocity was 1.2 m/s due east. The water was running at 0.4 m/s due west. John’s projected area in the water was 0.45 m2. Water density was 1000 kg/m3. The coefficient of drag was 0.2. (a) What was John’s velocity relative to the water? (b) What was the pressure drag force from the water? After a little while, John turned around and now is swimming at 1.2 m/s due west. (c) What is John’s velocity relative to the water now? (d) What is the pressure drag force from the water now? (e) What is the percentage of change in pressure drag force?

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Consider a particle with a charge-to-mass ratio of ?/? = 1 moving in a uniform magnetic...

Consider a particle with a charge-to-mass ratio of ?/? = 1 moving in a uniform magnetic field of B = 1 Tesla applied in z-direction. At time t = 0 s, it is located at r = (0, 10, 0) m and its velocity is v = (10, 0, 0) m/s.

(a) Qualitative motion

Draw a diagram of the situation when the proton starts its motion, showing its instantaneous velocity v0, the magnetic field vector B and the direction of the initial force F0 on the proton.

Describe how the velocity of the proton will change as it moves through the magnetic field. Describe changes, if any, in both the magnitude and direction of the velocity.

Describe the path the proton will follow in going through this uniform magnetic field.

Calculate the speed v of the proton.   
[8 marks]

(b) Quantitative motion

Determine the magnetic force acting on the proton initially.

Find the radius of the circular path the proton follows in terms of its charge q, mass m and speed v, and the strength of the magnetic field B. Then, calculate the numerical value of that radius for the proton.

Determine the time required and the angular frequency for one complete revolution.
[6 marks]

(c) Deriving equations of motion

Starting with the magnetic force on the particle and using Newton's second law to write down the differential equations for the components ax , ay and az of the acceleration a acting on the particle.

Describe the motion of the particle in z-direction if the initial velocity component in that direction vz is not zero. Describe how the overall motion of the particle changes in that case .
[6 marks]

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An object is placed 12 cm in front of a diverging lens with a focal length...

An object is placed 12 cm in front of a diverging lens with a focal length of 7.9 cm.

(a) Find the image distance and determine whether the image is real or virtual.

(b) Find the magnification

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A 110-kg rugby player is sliding on a muddy field at a speed of 2 m/s...

A 110-kg rugby player is sliding on a muddy field at a speed of 2 m/s toward the right as a 82-kg player is slipping at a speed of 3 m/s toward the left. As the two players collide, they grab onto each other and slide away together as one.

What kind of collision was this?

Set up the conservation of linear momentum for this collision, and determine the shared velocity (magnitude & direction) of the players immediately after the collision.

Would the players' total kinetic energy before the collision be equal to their total kinetic energy after? yes/no

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a) Explain the production of x-rays b) What is the typical energy range for Compton scattering...

a) Explain the production of x-rays

b) What is the typical energy range for Compton scattering and why?

c) Why does pair production require a minimal energy and what is it?

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What is the energy released in this alpha decay reaction 23090Th?22688Ra+42He90230Th?88226Ra+24He? (The atomic mass of 230Th230Th...

What is the energy released in this alpha decay reaction 23090Th?22688Ra+42He90230Th?88226Ra+24He? (The atomic mass of 230Th230Th is 230.033139 u and that of 226Ra226Ra is 226.025402 u)

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A stonemason is dragging a 60-kg marble block 4 m across a floor by pulling on...

  1. A stonemason is dragging a 60-kg marble block 4 m across a floor by pulling on a rope attached to the block. He pulls with a horizontal force of 210 N. The coefficient of kinetic friction between the block and the floor is 0.30.  The next five questions have to do with this scenario.  Draw yourself a free-body diagram on the block.

    How much work was done by the stonemason in dragging this block?

    a.

    100 J

    b.

    560 J

    c.

    840 J

    d.

    1230 J

  2. Add up the y-components, ΣFy, and determine the normal force the floor exerts upward on the block.

    a.

    588 N

    b.

    345 N

    c.

    279 N

    d.

    126 N

  3. Using your result from above, calculate the kinetic frictional force between the block and the floor.

    a.

    45.6 N

    b.

    56.7 N

    c.

    98.5 N

    d.

    176.4 N

Determine the work done by friction.

  1. a.

    345.2 J

    b.

    -705.6 J

    c.

    -980.1 J

    d.

    1257.9 J

  2. Add up the x-components, ΣFx , and determine the block's acceleration.

    a.

    3.7 m/s2

    b.

    0.91 m/s2

    c.

    0.56 m/s2

    d.

    0.38 m/s2

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Mark and his Harley Sportster has a combined mass of 950kg. a) Ignoring road and air...

Mark and his Harley Sportster has a combined mass of 950kg. a) Ignoring road and air friction, how much work is involved in accelerating the motorcycle from 0 to 100km/hr.
b) Mark claims that his 95hp cycle can go from 0 to 100 km/hr in 3.5 seconds. Assuming 100% efficiency, is this possible? Show how much horsepower is required.

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After a heavy snowfall, Annie wants to drag a sled loaded with toys across her level...

After a heavy snowfall, Annie wants to drag a sled loaded with toys across her level backyard floor, by pulling a rope at an angle of 26 degrees up from the snowy floor. When Annie increases her pull to 25N, the sled starts. Two days later, all the snow has melted leaving the concrete exposed. Annie pulls on the loaded sled, but now it has become harder to get it to start. Annie does not want to change the pulling angle, because it is most natural for her. Answer the 3 parts:

a) Draw a free body diagram for Annie's sled, labeling forces

b) The coefficients of static friction for snow and concrete are 0.15 and 0.95, respectively. How large is the normal force of the floor in the two cases (snow and concrete)?

c) How much mass does Annie need to remove from the sled, to be able to start the sled on the concrete by pulling just as hard as she did earlier on the snow?

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Estimate the number of Solar neutrinos passing through a detector on the Earth in one second....

Estimate the number of Solar neutrinos passing through a detector on the Earth in one second. Assume that the detector has a surface area of 1.0 square meters and is aligned so that it faces directly towards the centre of the Sun. Assume that every neutrino travels without any change (i.e. none are absorbed or converted to a different particle). Also assume that the energy carried out of the Sun by the neutrinos is negligible

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A ) A 2-?C point charge is embedded in the center of a solid Pyrex sphere...

A ) A 2-?C point charge is embedded in the center of a solid Pyrex sphere of radius R = 15 cm.

(1) Calculate the electric field strength E just beneath the surface of the sphere. (in N/C ) - Answer them in term of "e" like [ ex. : 1.43e+05? ]

(2) Assuming that there are no free charges, calculate the strength of the electric field just outside the surface of the sphere. ( in N/C ) Answer them in term of "e" like [ ex. : 1.43e+05? ]?

(3) What is the induced surface charge density ?ind on the surface of the Pryex? (in C/m^2) Answer them in term of "e" like [ ex. : 1.43e+05? ]?

________________________________________________________________________________

B) Trying with diffrent variables, a 1-?C point charge is embedded in the center of a solid Pyrex sphere of radius R = 12 cm.

(1) Calculate the electric field strength E just beneath the surface of the sphere.( in N/C )? Answer them in term of "e" like [ ex. : 1.43e+05? ]?

(2) Assuming that there are no free charges, calculate the strength of the electric field just outside the surface of the sphere.( in N/C )? Answer them in term of "e" like [ ex. : 1.43e+05? ]?

(3) What is the induced surface charge density ?ind on the surface of the Pryex?(in C/m^2) Answer them in term of "e" like [ ex. : 1.43e+05? ]

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A) Plot the first five particle in a box wavefunctions for an electron in a 10...

A) Plot the first five particle in a box wavefunctions for an electron in a 10 Å box

(starting at n = 1). Choose two of these and plot their probability density. Offer a brief

interpretation.

B) (10) Calculate the probability you would find the electron in the right-hand . of the

box (right-hand meaning larger values of the spatial variable) if the electron were

described by your fifth wavefunction (highest energy where n = 5). Calculate the

probability you would find the electron in the left-hand 1/4 of the box

C) (15) Suppose your electron were described as an equal superposition of the first and

second wavefunctions. Normalize this new function and then calculate the probability

you would find the electron in the right-hand 1/4 of the box. Calculate the probability

you would find the electron in the left-hand 1/4 of the box.

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A 190 Ω resistor, a 0.875 H inductor, and a 5.75 μF capacitor are connected in...

A 190 Ω resistor, a 0.875 H inductor, and a 5.75 μF capacitor are connected in series across a voltage source that has voltage amplitude 32.0 V and an angular frequency of 270 rad/s.

A. What is v at t= 22.0 ms ?

B. What is vR at t= 22.0 ms ?

C. What is vL at t= 22.0 ms ?

D. What is vC at t= 22.0 ms ?

E. Compare vC+vL+vR and v at this instant:

vC+vL+vR<v

vC+vL+vR>v

vC+vL+vR=v

which is true?

F. What is VR?

G. What is VC?

H. What is VL?

I. Compare V and VL+VC+VR:

VL+VR+VC=V

VL+VR+VC<V

VL+VR+VC>V

Which is true?

In: Physics