Please type down (easy for me to copy and paste) your response (thoughts, ie agree or diagree and why?) after your reading the following paragraphs. (min 5 sentences, 150-200 words)

Energy and climate is not only extremely important to the poorest, but yes I do agree that it is more important and affect them more than anyone else. It is best to acknowledge that there are people who did not know the scale or density of how much carbon is released into the atmosphere and how negatively it has impacted it. Now that fossil fuels and coals are what's essential to our everyday lives, that basically keeps our power on, it is extremely hard for us to aim to undo what has been done or even switch over to nuclear power plant just like that.

Nevertheless, if we as a people do not see climate change as a problem, our motivation in doing something about it or our aim to help improve our atmosphere is basically nonexistence. As Bill Gates said: "We need a new system, we need energy miracles". Gates have brought up 5 solutions, Solar Thermal, Solar Photovoltaic, Nuclear, Wind and Carbon Capture and Storage. I am more familiar with the solar and wind energy as being more efficient, though it will be definitely costly. Moreover, I would rather invest in solar energy because even though it may be expensive, in will still save a lot in the long run. Yes, Bill Gate is right that the sun doesn't shine all the time and the wind doesn't always blow. That is why we aim to create batteries that we store these energies for a long period of time. This is the type of investment that I rather my tax money goes into and also our focus as a society should be more towards.

Calcium reacts with sulfur (S8) forming calcium sulfide. What is the theoretical yield (g) of CaS(s) that could be prepared from 1.83 g of Ca(s) and 3.35 g of sulfur(s)? Enter your answer in decimal format with two decimal places and no units.

A four-wheel cart of mass M = 95 kg is moving along a horizontal surface with a constant velocity V = 3.5 m/s relative to the ground. A person of mass m1 = 65 kg carrying a backpack of m2 = 8 kg runs and catches up to the cart, and then jumps onto the cart. Just before landing on the cart, the person is moving parallel to the ground and the velocity of the center of mass of the system including the person, backpack and cart is VCM = 5 m/s.

What is the speed of the person just before landing on the cart?

v₀ = 5.3 m/s

v₀ = 12 m/s

v₀ = 0.45 m/s

v₀ = 7 m/s

v₀ = 8.8 m/s

2)

What is the horizontal momentum of the person after landing on the cart?

p_f = 325 kg m/s

p_f = 455 kg m/s

p_f = 228 kg m/s

3)

Compare the total kinetic energy of the system including the person, backpack and cart before the person has landed on the cart to after.

KE_before = KE_after

KE_before > KE_after

KE_before < KE_after

4)

The person now holds the backpack off the back of the cart and lets go. The backpack falls to the ground. What happens to the speed of the cart when the backpack is dropped?

increases

decreases

stays the same

(Note: Answers are D, A, B, C. Please show work and reasoning.)

(a) How long (in s) would it take a 1.00 ✕ 10⁵ kg airplane with engines that produce of 100 MW of power to reach a speed of 200 m/s and an altitude of 12.0 km if air resistance were negligible?

_? s

(b) If it actually takes 950 s, what is the power applied, in megawatts?

_? MW

(c)Given this power, what is the average force (in kN) of air resistance if the airplane takes 1200 s? (Hint: You must find the distance the plane travels in 1200 s assuming constant acceleration.)

_? kN

What is the phase shift of the TM and TE rays reflected both externally (air to glass) and internally (glass to air) for the situation discussed in Prob. 10?
Prob. 10 is Calculate the reflectance and transmittance for both TE and TM modes of light incident from air at 30 onto glass of index 1.60.

A basketball leaves a player's hands at a height of 2.25 m above the floor. The basket is 3.05 m above the floor. The player likes to shoot the ball at a 36.0 ∘ angle If the shot is made from a horizontal distance of 12.00 m and must be accurate to ±0.32 m (horizontally), what is the range of initial speeds allowed to make the basket?

Enter your answers numerically separated by a comma.

You and your friend go sledding. Out of curiosity, you measure the constant angle θ that the snow-covered slope makes with the horizontal. Next, you use the following method to determine the coefficient of friction µk between the snow and the sled. You give the sled a quick push up so that it will slide up the slope away from you. You wait for it to slide back down, timing the motion. It turns out that the sled takes four times as long to slide down as it does to reach the top point in the round trip. In terms of θ, what is the coefficient of friction? draw a free body diagram for the sled going up the slope and another for the sled coming down the slope, show all work and explain in 1 - 2 sentences why it takes longer for the sled to slide down the slope than to go up the slope

An AC generator supplies an rms voltage of 230 V at 60.0 Hz. It is connected in series with a 0.400 H inductor, a 3.40 μF capacitor and a 206 Ω resistor.

What is the impedance of the circuit? Tries 0/20

What is the rms current through the resistor? Tries 0/20

What is the average power dissipated in the circuit? Tries 0/20

What is the peak current through the resistor? Tries 0/20

What is the peak voltage across the inductor? Tries 0/20

What is the peak voltage across the capacitor? Tries 0/20

The generator frequency is now changed so that the circuit is in resonance. What is that new (resonance) frequency?

Select True or False for the following statements about electromagnetic waves. The sun's radiation is most intense in the visible region. Radio waves travel in vacuum at a lower speed than the visible light. The Earth's atmosphere is quite transparent to infrared radiation. Gamma rays can be produced through electrons oscillating in wires of electric circuits. Visible light is often emitted when valence electrons change their state. A vertical automobile antenna is sensitive to electric fields polarized vertically. X-rays travel in vacuum at a higher speed than the visible light.

An infinitely long conducting cylinder of radius 2 cm has a linear charge density +3 μC/m is surrounded by an insulating shell of inner radius 8 cm and outer radius 12 cm. The insulating shell has a net linear charge density of +3 μC/m which may be assumed to be uniformly distributed through its volume

What is the electric potential difference (ΔV) between 12 cm and 15 cm?

What is the electric potential difference (ΔV) between 8 cm and 12 cm?

What is the electric potential difference (ΔV) between 1 cm and 5 cm?

(a) How long (in s) would it take a 1.00 ✕ 10⁵ kg airplane with engines that produce of 100 MW of power to reach a speed of 200 m/s and an altitude of 12.0 km if air resistance were negligible?

_? s

(b) If it actually takes 950 s, what is the power applied, in megawatts?

_? MW

(c) Given this power, what is the average force (in kN) of air resistance if the airplane takes 1200 s? (Hint: You must find the distance the plane travels in 1200 s assuming constant acceleration.)

_? kN

Suppose that two blocks are positioned on an Atwood machine so that the block on the right of mass m1 hangs at a lower elevation than the block on the left of mass m2. Both blocks are at rest. Based on this observation, what can you conclude? A) m1>m2 B) m1<m2 C) m1=m2 D) You cannot conclude anything with the given information.

1.A particular material has a workfunction of (15.2 + A)/10 eV. Find the maximum wavelength of electromagnetic radiation that will result in the emission of photoelectrons from this surface. Give your answer in nanometers (nm) and with 3 significant figures. A: 19

2.Imagine the energy levels in an atom are given by E_n = - (8.30+A)eV/n². Find the wavelength of the photon emitted when an electron goes from n = (2+B) to n = 1. Give your answer in nanometers (nm) and with 3 significant figures. A:4 B:5

3. In the Bohr model for hydrogen, the energy levels are given by E_n = (-13.6eV) / n². Find the energy of a photon emitted when an electron in a hydrogen atom jumps from n = (A+3) to n = 2.

Calculate the answer in eV and make sure to include the unit. Report your final answer with three significant figures. A: 5

4. In an atom, an electron is jumping from state with an energy of –(2.45+(A/100)) eV to a state with an energy of –(5.24+(B/100)) eV. Find the wavelength of the emitted photon.

Give your answer in nm and make sure to include the unit. Report your final answer with three significant figures. A:54 B:11

Theory

a) How can you move a spacecraft just with solar radiation?

b) Explain how nanoparticle sunscreens can be transparent to the human eye, but still protect the skin.

c) What are the two main ways that nanoparticle sunscreens containing TiO2 or ZnO can protect your skin from ultraviolet radiation? [Note: the UV wavelengths of most concern are labelled UV-A (400-315nm) and UV-B (315-280nm)].

d) What is the largest size of TiO2 nanoparticle that could be used to make a transparent sunscreen (before to apply it)? [Hint: use the size parameter and wavelength of 500 nm]

e) What other factors would you need to consider before reducing the particle size to make a sunscreen transparent?

f) What colour would be the sky at noon (assuming normal incidence of the sun rays) if the atmosphere was made by 10 um particles?

g) Explain why is possible to do sensing with plasmonic nanoparticles.

h) Explain the working principle of a microwave oven. Would it still work if you doubled the wavelength of the exciting radiation?

i) Is it possible to detect spherical particles in air with a diameter of 1nm with the IR light? Comment the answer.

j) Is the Rayleigh scattering at λ=400 nm greater or smaller than the one at λ=700 nm for equal incident intensity of light? Explain the answer.

You and your friend Peter are putting new shingles on a roof pitched at 23 ∘ . You're sitting on the very top of the roof when Peter, who is at the edge of the roof directly below you, 5.0 m away, asks you for the box of nails. Rather than carry the 2.5 kg box of nails down to Peter, you decide to give the box a push and have it slide down to him.

If the coefficient of kinetic friction between the box and the roof is 0.55, with what speed should you push the box to have it gently come to rest right at the edge of the roof?