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A statistical process control chart was used to monitor improvement, with control limits set at 3 SDs and a shift of more than 8 points above or below the mean being indicative of special cause variation.

In the vertical jump, an athlete starts from a crouch and jumps upward to reach as high as possible. Even the best athletes spend little more than 1.00s in the air. Treat the athlete as a particle and let y max be his maximum height above the floor.

To explain why he hangs in the air, calculate the ratio of the time he is above ymax/2 (moving up from ymax/2 and then moving down to ymax/2) to the time it takes him to go from the floor to that height. You may ignore air resistance.

Please someone help me, the answer is close to 5 apparently, but I don't know how to get it, all my answers are way off!

In the vertical jump, an athlete starts from a crouch and jumps upward to reach as high as possible. Even the best athletes spend little more than 1.00s in the air. Treat the athlete as a particle and let y max be his maximum height above the floor.

To explain why he hangs in the air, calculate the ratio of the time he is above ymax/2 (moving up from ymax/2 and then moving down to ymax/2) to the time it takes him to go from the floor to that height. You may ignore air resistance.

Please someone help me!

basically I had sex two days before my period was due and my period came as normal, and I didn't have any sexual contact the next month, but my next period, which was on time, was more like a brown bloody discharge which lasted five days. The bleeding has stopped now but I still have a sore back and pelvic cramps, and I'm panicking that I'm pregnant!!

I've applied for my student loan and bursary and received my award notice over a month ago. It said on the award notice that they would write to me asking for proof of income so that they could confirm my award but they've still not got back to me. I'm starting to think that I was supposed to just send them the proof of income at the time of application. Does anyone know how it works???

I'm doing a physics project in which I'm trying to experimentally determine the wavelength of sodium light. I used the Michelson Interferometer method but the results are confusing me. What do you do to calculate the correction factor, I don't get it :(

Thanks for any help.

Really confused :(

What should the radius of curvature be roughly if I have a plano convex lens of focal length 100cm and diameter 32cm. I've tried doing it experimentally with a spherometer but it doesn't seem to be working.

I know it has something to do with paracetamol solubility, but could anyone explain it in more detail? Thanks.

Why is a force required to keep a body in a circular path?

A cyclist jumps on his bike and starts to pedal until he reaches a steady speed.

i) If a spoke makes 3 complete revolutions in 6 s, calculate the angular velocity of a point on the wheel. ii) The cyclist pedals harder and the spoke now makes 1.5 revolutions in 1.5s. If this increase took place in 2 s, calculate the angular acceleration of the wheel. iii) Calculate the angular displacement of a point on the wheel during the angular acceleration. iv) The cyclist stops pedalling and his bike slows down to a complete rest in 5 s. Calculate the angular acceleration of the bike. v) To test his understanding of angular motion, the cyclist measured the distance he travelled form from the instant he pedalled harder to the instant he stopped. He then used the equations of angular motion to confirm that calculation agreed with measurement. What measurement would he need to make before he could do this? Estimate this quantity and calculate the distance he would have calculated.

7) A UV source is producing photons of wavelength 375 nm. The source is 50.0 cm from an 8.0 cm2 zinc plate which absorbs 5 J of light energy per second.

i) How many photons of UV are incident on the zinc plate per second?

ii) The UV source is moved to a distance of 0.75 cm from the zinc plate, how many photons per second are incident on the plate now? You may assume the UV source is a point source.

iii) Calculate the kinetic energy of the photo-electrons at both distances. The work function for Zinc is 5.2 x 10-19 J.

iv) Consider your answers to ii) and iii) and explain what would be actually observed if the light-plate distance increased (or decreased).

If the Earth is 150 million km from the Sun and Mars is 207 million km from the sun, what is the ratio Iearth : Imars where Iearth is the irradiance at the Earth due to the Sun, hence find the irradiance at Mars if the Earth’s irradiance is 120 Wm-2.

Plus working.

Thanks.

I know how to work out the area between 2 curves, but what would you do if there were 3 curves?

A mixture of sodium chloride and sodium sulphate is known to contain 0.6mol of chloride ions and 0.2mol of sulphate ions.

How many moles sodium ions are present?

Plus working.

Thanks.

I'm really stuck on this question, I don't really know how to do any of it.

A mixture of green and blue light is incident on a diffraction grating of 200 lines per mm. An interference pattern is seen on a screen 2.0 m from the grating.

i) Identify the colours, 1, 2 and 3.

ii) Calculate theta2 – theta1. Use wavelengths 380 nm and 450 nm.

iii) Suppose you wished to increase theta2 – theta1 , what would you do?

There's a link which shows the question with a diagram.

http://www.theyoungscottishphysicist.co.uk/Higher/...

Plus working.

Thanks.

An element melts at about room temperature and forms an oxide which reacts with water to form a solution with a pH less than 7. Which statement is most likely to be true\\\\/

A the element conducts electricity

B the oxide contains covalent bonds

C the oxide has a high melting point

D the element has a covalent network structure

Thanks.

A metal (melting point 843degreesC, density 1.54gcm^3) was obtained by electrolysis of its chloride (melting point 772degreesC, density 2.15gcm^3). During electrolysis the metal would occur as:

A a solid on the surface of the electrolyte

B a liquid on the surface of the electrolyte

C a solid at the bottom of the electrolyte

D a liquid at the bottom of the electrolyte

Thanks.

A compound boils at -33 degrees celcius. It also dissolves in water to give an alkaline solution. What type of bonding is present within this molecule?

A metallic

B covalent (polar)

C ionic

D covalent (non polar)

Thanks.