A 38.0-kg crate is being pushed along a horizontal surface. The applied force is 94.0 N directed at an angle of 18.0° below the horizontal and the coefficient of friction is .21.

a)  Draw a free body diagram for the crate.

b)  Write expressions for the x and y components of the applied force (no numbers).

c)  Sum forces in the x and y direction (no numbers).

d)  Solve:  What is the acceleration of the crate?

The cube in the figure has edge length 1.20 m and is oriented as shown in a region of uniform electric field. Find the electric flux through the right face if the electric field (a) is in the positive x direction and has magnitude 7.52 N/C, (b) is in the negative y direction and has magnitude 2.68 N/C, and (c) is in the xz plane, has x component -3.16 N/C, and has z component 4.82 N/C. (d) What is the total flux through the cube's surface for each field? (a) Number Units (b) Number Units (c) Number Units (d) Number Units

Thermodynamics and Statistical Mechanics problem:

Write the formula for the partition function Z of an electron in a hydrogen atom. If the sum is finite, to what value does it converge? If the sum is infinite, prove it

A child of mass m_c = 35 kg stands on the rim of a frictionless merry go round, which acts like a solid disk of mass m_m = 55 kg and radius r = 1.1 m. With the merry go round at rest, they throw a rock of mass m_r = 1.0 kg with a velocity v = 18 m/s relative to the ground in a direction horizontal to the ground, and tangent to the rim of the merry go round.

1. What is the magnitude of the angular momentum of the rock around the axis of the merry go round?
2. What is the angular velocity of the merry go round after the rock is thrown?
3. One of the child’s friends holds their hand against the rim of the merry go round and causes it to stop in a time interval of 3.2 s. What is the magnitude of the frictional force applied?

1. William leaves Kitchener and Mike leaves Rockwood at the same time both headed towards each others’ city along identical routes. They both have constant speeds but Mike’s is greater. They pass each other at noon without stopping. If Mike hikes into Kitchener at 1:00 PM and William reaches Rockwood at 2:15 PM at what time did they both set off? Hint: Draw a position diagram and find an equation for each distance.

For astronomy class, please answer this question clearly, thank you .

Titan’s atmosphere contains a large amount of photosensitive methane. We know because of basic physics and chemistry that there must be a source of methane on Titan that replenishes the atmospheric methane.

a) Describe what astronomers thought might be occurring on Titan before the Cassini/Huygens mission.

b) Describe the findings of the Cassini/Huygens mission that either supported or disproved the original hypotheses.

An electron is trapped in a two-dimensional region of ?? =??= 1.00x10-10 m (a typical atomic diameter). a. Find the energies of the ground state and first two excited states. b. How much energy must be supplied to excite the electron from the ground state to the second excited state? c. From the second excited state, the electron drops down to the first excited state. How much energy is released in this process?

Derive the moment of inertia, of triatomic linear rotors

(a) An object is subjected to the force F = 3x³ z ı ^ + 5 z^{2k ^} N, where x and z are in metres. The object can only move in the xz-plane.

          (i) The object moves from the origin by moving first along the x-axis to (a, 0) and then parallel to the z-axis to the point with coordinates (a,b). How much work does the force do?

[2 marks]

          (ii) The object moves from the origin by moving first along the z-axis to (0,b) and then parallel to the x-axis to the point with coordinates (a,b). How much work does the force do?

[2 marks]

          (iii) Is this a conservative force?

[1 mark]

          (iv) Can this force be expressed as the gradient of a potential? If so, give an expression for the potential. If not, give reasons why.

[2 marks]

(b) In the figure, we show a spring compressed by 85 cm. It is used to launch a physics student of mass 88 kg. The track is frictionless until it starts up the incline. Assume that the acceleration of gravity is 9.8 m/s². The student has a coefficient of kinetic friction of 0.23 on the 30^o incline.

Figure 3 (If the image above does not appear, click here.)

          (i) What is the student's speed just after losing contact with the spring?

[3 marks]

          (ii) Once the student has reached the lowest point on the track, they continue back up the other side, slowed down by friction and gravity. How far does the student travel up the incline before stopping?

[3 marks]

A roller coaster starts at ground level and rises up 139 m above the ground on the first hill. What is the maximum speed it can have when it rolls down to the ground level?

1.The same horizontal force, of magnitude F, is applied to two different blocks, of mass m and 3m The blocks move on a frictionless surface and both blocks begin from rest. If each block moves the same distance as the force is applied, which one of the following sentences is true?

A)The lighter block acquires 9 times as much kinetic energy as the heavier block.

B)The two blocks acquire the same kinetic energy.

C)The heavier block acquires 3 times as much kinetic energy as the lighter block.

D)The lighter block acquires 3 times as much kinetic energy as the heavier block.

E)The heavier block acquires 9 times as much kinetic energy as the lighter block.

Note: I initially came up with C as my answer, but it is supposably wrong.

1.1 Two identical objects of the same mass, initially at rest, are accelerated through the same distance by different forces such that one object gains velocity twice that of the other object. One can conclude that the force on the faster object is _________

A)10 times that of the slower object

B)Half that of the slower object

C)16 times that of the slower object

D)Twice that of the slower object

E)Four times that of the slower object.   

F)Three times that of the slower object

Please help and explain as I want to understand the question and answer. Thank you.

Consider an atom with four energy levels, where the lowest energy is -10 eV and the highest level is 0 eV. Sketch an energy-level diagram that could produce the spectrum. What are the energies of the other two energy levels. (Note: there are more than two answers.)

A -2 eV and -5 eV

B -1 eV and -4 eV

C -1 eV and -6 eV

D -6 eV and -9 eV

E -7 eV and -3 eV

A student put a red rose under blue light and the rose appears black. Student places rose under red light and it appears red. Explain this student's conclusion using the laws of physics and color.

I am playing pool and i hit a trick shot. I hit the ball at an angle 55 degrees. with a force of 10 newtons for .4seconds. The ball ihas a radius of 0.05m and a mass of .150kg. and the coeeficient of kinetic friction is 0.3.

1) determine the initial linear and angular velocity after i hit the ball? determine the distance the ball travels after it it and before it goes back? Determine the final velocity? answer all.