Concave makes things smaller and convex makes things bigger
Answer:
The shortest de Broglie wavelength for the electrons that are produced as photoelectrons is 0.81 nm
Explanation:
Given;
wavelength of ultraviolet light, λ = 270 nm
work function of the metal, φ = 2.3 eV = 2.3 x 1.602 x 10⁻¹⁹ J = 3.685 x 10⁻¹⁹ J
The energy of the ultraviolet light is given by;

The energy of the incident light is related to kinetic energy of the electron and work function of the metal by the following equation;
E = φ + K.E
K.E = E - φ
K.E = (7.362 x 10⁻¹⁹ J) - (3.685 x 10⁻¹⁹ J )
K.E = 3.677 x 10⁻¹⁹ J
K.E = ¹/₂mv²
mv² = 2K.E
velocity of the electron is given by;

the shortest de Broglie wavelength for the electrons is given by;

Therefore, the shortest de Broglie wavelength for the electrons that are produced as photoelectrons is 0.81 nm
ANSWER:
The study and analysis of light according to its component wavelengths is called spectroscopy.
EXPLANATION:
Spectroscopy is the branch of science that is concerned with the investigation and measurement of spectrum produced when matter interacts with or emits electromagnetic radiation.It helps us to identify atoms and molecules in the object.Spectroscopy is used to find out Dopplers effect (the red shift and blue shift),which tells how fast the object is comming towards earth or moving away from the earth.
Answer:
<em>Thus, the object is accelerating to the left</em>
Explanation:
<u>The Net Force</u>
The net force is the result of adding all the forces as vectors acting on a body.

Each vector can be expressed in its rectangular components Fx and Fy, and the sum is the sum of the rectangular components separately.
Second Newton's law gives the relation between the net force and the acceleration of the body:

We can see the acceleration is a vector with the same direction as the net force.
The diagram shows two vertical forces and two horizontal forces.
The vertical forces are acting in opposite directions and with the same magnitude, thus they cancel out, leaving zero net force in the y-axis.
The horizontal forces are opposite and with different magnitudes. Since the force acting to the left (F3) has a greater magnitude than the force acting to the right (F4), there is a net force directed to the left with a magnitude of 60 N - 20 N = 40 N
Thus, the object is accelerating to the left
Answer: the mass of the second ball is 2.631 kg
Explanation:
Given that;
m1 = 0.877 kg
Initial velocity = V0
Initial momentum = m1 × V0
final velocity of m1 is u1, final velocity of m2 is u2 = v0/2
now final momentum = m1 × u1 + m2 × u2
using momentum conservation;
m1×V0 = m1×u1 + m2×v0/2
m1×(v0 - u1) = m2×V0/2 ----- let this be equation 1
Now, for elastic collision;
m1×v0²/2 = m1×u1²/2 + m2×(v0/2)²/2
m1×(v0² - u1²) = m2×(v0/2)² --------- let this be equation 2
now; equation 2 / equation 1
: V0 + u1 = v0/2
2V0 + 2u1 = V0
2u1 = V0 - 2V0
u1 = -V0/2
now we insert in equ 1
m1×3V0/2= m2×V0/2
m1 × 3 = m2
m2 = 0.877 × 3
m2 = 2.631 kg
Therefore, the mass of the second ball is 2.631 kg