1. A 5.40 g coin is placed 17.0 cm from the center of a turntable. The coin has static and kinetic coefficients of friction with the turntable surface of μs = 0.810 and μk = 0.460.

Part A: What is the maximum angular velocity with which the turntable can spin without the coin sliding? Express your answer with the appropriate units.

2. A 800 g ball moves in a vertical circle on a 1.09 m -long string. If the speed at the top is 4.30 m/s , then the speed at the bottom will be 7.82 m/s .

Part A: What is the ball's weight? Express your answer with the appropriate units.

Part B: What is the tension in the string when the ball is at the top? Express your answer with the appropriate units.

Part C: What is the tension in the string when the ball is at the bottom? Express your answer with the appropriate units.

1. Advanced skiers turn by sliding the backs of their skis across the snow. Since the fronts of their skis don’t move much, the skis end up pointed in a new direction.

a. The amount of sideways force that a skier must exert on the skis to slide them sideways is proportional to how hard the skis press down on the snow beneath them. Why?

b. Less skilled skiers sometimes turn without unweighting—they push their skis sideways so hard that the skis slide anyway. This technique is exhausting. Why does it require so much work?

c. Why is wax used on skis? Why wouldn’t WD-40 work as well as the wax? What is in WD-40?

A Kaon K⁺ breaks down into two particles. From amongst the following three particles:

π⁰ (neutral pion)

η⁰ (eta meson)

μ⁺ (anti-muon, identical to a muon except for its electric charge)

which one(s) can be formed as the products of the described break-down? (the other product is not known).

a. π⁰

b. η⁰

c. μ⁺

d. η⁰, π⁰

e. μ⁺, π⁰

f. μ⁺, η⁰

g. all three of them

h. none of them

Please reason your answer based on the various laws of conservation, and explain in precise terms why each one the three particles can or cannot be the product of the breakdown.

Thank you!

An acoustic signal is composed of the first three harmonics of a wave of fundamental frequency 425 Hz. If these harmonics are described, in order, by cosine waves with amplitudes of 0.630, 0.900, and 0.650, what is the total amplitude of the signal at time 0.825 seconds? Assume the waves have phase angles θ_n = 0.

List and briefly discuss three significant considerations when measuring very small currents. this qiestion is related to photoelectric effect lab

1. A new car is tested on a 290-m-diameter track. If the car speeds up at a steady 1.2 m/s2 , how long after starting is the magnitude of its centripetal acceleration equal to the tangential acceleration? Express your answer to two significant figures and include the appropriate units.

2. A concrete highway curve of radius 80.0 m is banked at a 15.0 ∘ angle.

Part A: What is the maximum speed with which a 1300 kg rubber-tired car can take this curve without sliding? (Take the static coefficient of friction of rubber on concrete to be 1.0.) Express your answer with the appropriate units.

3. A 4 kg ball swings in a vertical circle on the end of an 80-cm-long string. The tension in the string is 20 N when its angle from the highest point on the circle is θ=30∘.

Part A: What is the ball's speed when θ=30∘? Express your answer to two significant figures and include the appropriate units.

Part B: What is the magnitude of the ball's acceleration when θ=30∘? Express your answer to two significant figures and include the appropriate units.

Part C: What is the direction of the ball's acceleration when θ=30∘? Give the direction as an angle from the r-axis. Express your answer to two significant figures and include the appropriate units.

A 3.20-m-long, 500 kg steel uniform beam extends horizontally from the point where it has been bolted to the framework of a new building under construction. A 70 kg construction worker stands at the far end of the beam.

What is the magnitude of the torque about the bolt due to the worker and the weight of the beam?

3)A person with mass m1 = 80 kg stands at the left end of a uniform beam with mass m2 = 100 kg and a length L = 4.0 m. Another person with mass m3 = 110 kg stands on the far right end of the beam and holds a medicine ball with mass m4 = 10 kg (assume that the medicine ball is at the far right end of the beam as well). Let the origin of our coordinate system be the left end of the original position of the beam as shown in the drawing. Assume there is no friction between the beam and floor.

A) What is the initial location of the center of mass of the system?

B) What is the initial velocity of the center of mass of the system?

C) The ball is thrown to the left end of the beam. Where is the center of mass now?

D) The two people now switch places on the beam. Where is the center of mass now?

E) Both people walk to the center of the beam. At what x-position do they end up?

DIFFERENTIAL EQUATIONS

An 8-lb weight is attached to the lower end of a coil spring suspended from a fixed support. The weight comes to rest in its equilibrium position, thereby stretching the spring 6 in. The weight is then pulled down 9 in. below its equilibrium position and released at t=0. The medium offers a resistance in pounds numerically equal to 4x', where x' is the instantaneous velocity in feet per second. Determine the displacement of the weight as a function of the time.

Please be clear with how you arrive to the answer, I have a quiz coming up and want to make sure I do this correctly! Thank you very much

Cover chapter 2 (solar and IR radiation) and the beginning of chapter 3 (thermodynamics) of the Stull book.Write out the question before responding to the question. Perform a units check for each formula. Answers must include units to receive full credit.

.(a) Compute the mass flux (kg m-2 s -1 ) at sea level, for a measured kinematic mass flux of 21ms-1 .

(b) Suppose that this kinematic mass flux was made at an altitude of 3km in an adiabatic atmosphere with the sea level temperature of 20°C, what is the mass flux in this situation?

(c) Estimate the value of solar irradiance reaching the orbit of Jupiter.

(d) If the solar radiation changes by +/- 10%, what is the corresponding change to the solar irradiance reaching the planet Venus?

1. The pilot of rocket A, moving at a velocity of 0.8c relative to earth, observes a second rocket B that moves along the same line approaching him from behind at 0.7c. What does an observer on earth measure for the second rocket’s velocity?
2. For observer S, a meter stick at rest makes an angle of 25 degrees with the x-x’ axis. How long is that meter stick for S? An observer S’ who moves along the y-y’-axis at 0.5c sees what length and what angle for the meter stick?

Please include diagrams:

a) A 100-W light bulb and a 40-W light bulb are both rated at household voltage. i) Which light bulb will be brighter if the two bulbs are connected in parallel and this combination connected to a household voltage source? ii) Which light bulb will be brighter if they are connected in series and this combination connected to a household voltage? b) A battery charges a parallel plate capacitor. After it is fully charged, it is then disconnected from the battery and the gap between the plates is filled with a dielectric. How does the charge on the plates and the potential difference between them change? c) A battery is used to charge a parallel plate capacitor. After it is fully charged, the battery is disconnected and the plates are pulled apart. What happens to the potential energy stored in the capacitor and the potential difference across the capacitor?