Answer:
Lithium
Explanation:
The equation for the photoelectric effect is
where
is the energy of the incident photon, with
h being the Planck constant
c is the speed of light
is the wavelength of the photon
is the work function of the metal (the minimum energy needed to extract the photoelectron from the metal)
is the maximum kinetic energy of the emitted photoelectrons
In this problem, we have
is the wavelength of the incident photon
is the maximum kinetic energy of the electrons
First of all we can find the energy of the incident photon
Converting into electronvolts,
So now we can re-arrange the equation of the photoelectric effect to find the work function of the metal
So the metal is most likely Lithium, which has a work function of 2.5 eV.
I think its c I really don't take physics but I try to help.
Answer:
Liquid has a defined volume but undefined shape
Explanation:
Explanation:
Solid has specific shape and volume
Liquid has specific volume but no specific shape
Gases have no specific volume and no specific shape
So correct answer is liquid.
Answer:
F = 5226.6 N
Explanation:
To solve a lever, the rotational equilibrium relation must be used.
We place the reference system on the fulcrum (pivot point) and assume that the positive direction is counterclockwise
F d₁ = W d₂
where F is the applied force, W is the weight to be lifted, d₁ and d₂ are the distances from the fulcrum.
In this case the length of the lever is L = 5m, t the distance desired by the fulcrum from the weight to be lifted is
d₂ = 200 cm = 2 m
therefore the distance to the applied force is
d₁ = L -d₂
d₁ = 5 -2
d₁= 3m
we clear from the equation
F = W d₂ / d₁
W = m g
F = m g d₂ / d₁
we calculate
F = 800 9.8 2/3
F = 5226.6 N
The formula for frequency is f = 1/T where f is frequency and T is period in seconds.
You have you period which is 0.008s and that is all you will need to solve or frequency in a wave:
f = 1/2
f = 1/0.008s
f = 125Hz
