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Define a "Vector Quantity" and list 2 examples.

a) A vector quantity is a quantity with both magnitude and direction. (opposite would be a "scalar quantity") b) examples could include acceleration, weight, displacement, velocity etc.
TF
Answered by Thomas F. • Physics tutor
3387 Views

If the force between two point charges of charge 'Q1' and 'Q2' which are a distance 'r' apart is 'F' then what would the force be if the charge of 'Q1' is tripled and the distance between them doubled?

We know from Coulombs law that the force between two point charges is directly proportional to the product of the magnitudes of each charge and inversley proportional to the square of the distance between th...
JH
Answered by Joseph H. • Physics tutor
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A gun of mass 10kg fires a bullet of mass 240g at a speed of 300ms-1. What is the speed of the gun's recoil?

First, convert the mass of the bullet into SI units -> 240g=0.24kg The law of the conservation of momentum states that m 1 v 1 =m 2 v 2 . To find the speed of the gun, rearrange for v 1 to give v 1 =m 2 v...
JF
Answered by Jonny F. • Physics tutor
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Derive an expression for the centripetal acceleration of a body in uniform circular motion.

(I assume familiarity with positions represented by vectors and differentiation of trigonometric functions). Consider the coordinates of a point moving in a circle of radius r around the origin. The equation...
HA
Answered by Hubert A. • Physics tutor
4085 Views

Calculate the threshold frequency for a metal with a work function of 3eV

The equation for work function is: W = hf So, this is rearranged to: f = W/h where h is planck's constant. Therefore, if we know the work function then we can work out the threshold frequency. Don't forget t...
AW
Answered by Anna W. • Physics tutor
98632 Views