Answer:
b. AG, work function=4.74eV
Explanation:
Ultraviolet light starts at the end of the visible light spectrum, where violet light ends:
(wavelength of lowest-energy ultraviolet light)
So, the lowest energy of ultraviolet light can be found by using the formula

where
h is the Planck constant
c is the speed of light
Substituting,

And keeping in mind that

This energy converted into electronvolts is

The work function of a metal is the minimum energy needed to extract a photoelectron from the surface of the metal. Therefore, the metals that exhibit photoelectric effect are the ones whose work function is larger than the energy we found previously, so:
b. AG, work function=4.74eV
Because for all the other metals, visible light will be enough to extract photoelectrons.
<span>René Descartes suggests this.</span>
(1) acceleration, a = 4 m/
(2) acceleration of 10 N,
= 1 m/
and acceleration of 30 N,
= 3 m/
Explanation:
- Here, the acceleration of the object could be found using the equation derived in the second law of motion. The equation is given as, F = ma where m is the acceleration of the object, m is the mass of the object and F is the applied on the object.
- Let
be the acceleration for force 10 N, to find acceleration rearrange the equation to a =
. When we substitute 10 N force and 10 kg mass of the box in the equation. We will get
= 1 m/
- Let
be the acceleration for force 30 N, to find acceleration rearrange the equation to F =
. When we substitute 30 N force and 10 kg mass of the box in the equation. We will get
= 3 m/
- To find the combined, just add the force and substitute in the above equation. Hence, a = 4 m/

Answer:
B) 2.2 Ω
Explanation:
First of all, we should notice that the resistor placed between A and B is short-circuited. In fact, the current from point A will follow the wire above between A and C (which has zero resistance), so we can basically ignore the presence of the resistor between A and B, since it has no effect on the circuit.
Then, we can notice that the two resistors between CB and CD are in parallel to each other; therefore, their equivalent resistance is given by:
