Answer:
b
Explanation:
I think so I'm not 100% sure sorry
Answer:
The work function ϕ of the metal = 53.4196 x 10⁻¹⁶ J
Explanation:
When light is incident on a photoelectric material like metal, photoelectrons are emitted from the surface of the metal. This process is called photoelectric effect.
The relationship between the maximum kinetic energy (
) of the photoelectrons to the frequency of the absorbed photons (f) and the threshold frequency (f₀) of the photoemissive metal surface is:
= h(f − f₀)
= hf - hf₀
E is the energy of the absorbed photons: E = hf
ϕ is the work function of the surface: ϕ = hf₀
= E - ϕ
Frequency f = 8.12×10¹⁸ Hz
Maximum kinetic energy
= 4.16×10⁻¹⁷ J
Speed of light c = 3 x 10⁸ m/s
Planck's constant h = 6.63 × 10⁻³⁴ Js
E = hf = 6.63 × 10⁻³⁴ x 8.12×10¹⁸
E = 53.8356 x 10⁻¹⁶ J
from
= E - ϕ ;
ϕ = E - 
ϕ = 53.8356 x 10⁻¹⁶ - 4.16×10⁻¹⁷
ϕ = 53.4196 x 10⁻¹⁶ J
The work function of the metal ϕ = 53.4196 x 10⁻¹⁶ J
Answer:The cannons total flight time is 2.23seconds
Explanation:
A ball fired diagonally is fired at an angle of 45° to the horizontal. The motion of the fired ball is a projectile motion. A projectile is a motion in which an object fired into space with an initial velocity U is allowed to fall freely under the influence of gravitational force.
To total time of flight T of the cannon ball can be expressed as;
T = 2Usin(theta)/g where;
U is the initial velocity or speed of the ball = 31m/s
theta is the angle that the ball make with the horizontal = 45°
g is the acceleration due to gravity = 9.81m/s²
Substituting the given datas into the formula we have;
T = 31sin45°/9.81
T = 31×0.7071/9.81
T = 21.92/9.81
T = 2.23seconds
Answer:24888.8g
Explanation: 28cupcakes calls 360g
32 cupcakes calls ???
28x32=896 cupcakes
896/360= 2.4888888g
In four decimal place = 24888.8grams