Answer:
λ = 2.7608 x 10⁻⁷ m = 276.08 nm
Explanation:
The work function of a metallic surface is the minimum amount of photon energy required to release the photo-electrons from the surface of metal. The work function is given by the following formula:
Work Function = hc/λ
where,
Work Function = (4.5 eV)(1.6 x 10⁻¹⁹ J/1 eV) = 7.2 x 10⁻¹⁹ J
h = Plank's Constant = 6.626 x 10⁻³⁴ J.s
c = speed of light = 3 x 10⁸ m/s
λ = longest wavelength capable of releasing electron.
Therefore,
7.2 x 10⁻¹⁹ J = (6.626 x 10⁻³⁴ J.s)(3 x 10⁸ m/s)/λ
λ = (6.626 x 10⁻³⁴ J.s)(3 x 10⁸ m/s)/(7.2 x 10⁻¹⁹ J)
<u>λ = 2.7608 x 10⁻⁷ m = 276.08 nm</u>
"Acceleration" does NOT mean speeding up. It also doesn't mean
slowing down. Acceleration means ANY change in the speed
OR DIRECTION of motion.
The only kind of motion that's NOT accelerated is motion at a steady
speed AND in a straight line.
Even when your speed is steady, you're accelerating if your direction
is changing.
A few examples:
(no speeds are changing):
-- driving on a curved road, or turning a corner
-- going around a curve on a skateboard, a bike, or a Segway
-- running on a quarter-mile track
-- an Indy car cruising a practice lap around the track
-- water spinning, getting ready to go down the drain
-- any point on the blade of a fan
-- the little ball going around the inside of a Roulette wheel
-- the Moon in its orbit around the Earth
-- the Earth in its orbit around the sun
Answer: Yes, he is exceeding the speed limit
Explanation:
Hi!
This is problem about unit conversion
1 mile = 1,609.344 m
Then the speed limit v is:
v = 75 mi/h = 120,700.8 m/h
1 hour = 60 min = 60*60 s = 3,600 s
v = (120,700.8/3,600) m/s = 33.52 m/s
38 m/s is higher than the speed limit v.
Answer:
Explanation:
F = ma
a = F/m
a = (200.0 + 150.0 - 100.0) / 91.0
a = 250.0/91.0
a = 2.7472527...
a = 2.75 m/s²
Answer:
The direction in which a positive charge would move.
Explanation:
The direction of an electric current is by convention the direction in which a positive charge would move. Thus, the current in the external circuit is directed away from the positive terminal and toward the negative terminal of the battery. Electrons would actually move through the wires in the opposite direction.
