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State Newton's 1st Law:

An object will remain at rest or constant velocity if all the forces acting upon it are equal (net force=0N).

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If photons of wavelength 0.1nm are incident on a 2m x 2m Solar Panel at a rate of 2.51x10^15s^-1, calculate the intensity, I, of the photons on the Solar Panel.

If wavelength = 0.1nm, we know (as E=hc/λ), the energy provided by each photon, E= 1.99x10¹⁵J .Therefore, if they hit the panel at a rate of 2.51x10¹⁵

Answered by Sam H. • Physics tutor

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How many Protons, Neutrons and Electrons are there in an atom of Silicon, Si?

Using a copy of the periodic table, look up the Mass and Atomic numbers of Silicon. Mass number = 28; Atomic number = 14. The Atomic number is equivalent to the number of Protons in an atom, so there are ...

Answered by Eloise S. • Chemistry tutor

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Given a right-angled triangle with an angle of 35 degrees and an Opposite side of 12cm, calculate the length of the hypotenuse to 3 significant figures.

First, determine which of SOH-CAH-TOA you need to use. As this question involves the Hypotenuse and the Opposite side, use Sine. As such, write out the equation as: sin(35) = 12/x. (Let x represent the Hy...

Answered by Eloise S. • Maths tutor

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Solve for x to 3dp: x^2 + 6x + 2 = 0

We cannot factorise this so we shall use the quadratic formula instead.We need to substitute in the values for a, b, and c.ax² + bx + c = 0x² + 6x + 2 = 0a = 1, b=6, c=2Once substitu...

Answered by Rikesh S. • Maths tutor

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