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In the Photoelectric Effect, what is mean by 'threshold frequency' and how does the magnitude a photons frequency effect the electron it is absorbed by?

The threshold frequency is the minimum frequency a photon can be and still just overcome the work function (Φ) of a particular material. The threshold frequency is directly proportional to the work function ...
JH
Answered by Josh H. • Physics tutor
15487 Views

How do you calculate the total resistance of two resistors, R1 and R2, when they are in series and when they are in parallel?

When resistors are in series you may add up their resistances to find the total resistance, R Total = R1 + R2. However, when resistors are in parallel, it gets a little more complicated. You must use the equ...
JM
Answered by Jamie M. • Physics tutor
14944 Views

How many times further away from the pivot point of a seesaw does someone of double the weight have to sit in order for the it to balance?

Sum of moments in equilibrium must equal 0. The sum of clockwise moments must equal the sum of anticlockwise moments. W1 is the force exerted on the seesaw by the heavy person at distance D1 from the pivot a...
RM
Answered by River M. • Physics tutor
3388 Views

By considering Newton's second law and his law of gravitation, derive an expression for gravitational field strength g in terms of its mass, m, the distance from its center of mass, r, and the gravitational constant, G.

Newton's second law of motion is F = ma and his law of gravitation is F= GMm/r^2.g is the acceleration of free fall and can be substituted for a, F = mg.We can therefore see that g = F/m and can use that to ...
RM
Answered by River M. • Physics tutor
2425 Views

What is are elastic and inelastic collisions?

A collision is elastic when the total amount of kinetic energy in the system is conserved, there is no loss in kinetic energy. A collision is inelastic when the total amount of kinetic energy in the system i...
AR
Answered by Adam R. • Physics tutor
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