Answer:
Light of a shorter wavelength should be used.
Explanation:
This is studied in the phenomenon called photoelectric effect, in which light is able to release electrons from a metal, said electrons are called photoelectrons .
The experiments that have been carried out show that <u>increasing or decreasing the intensity of the light will not cause the photoelectrons to be emitted</u>, what will cause the photoelectrons to be emitted is to increase the frequency of the incident light.
And a higher frequency corresponds to a shorter wavelength according to the equation:
(where 
is frequency, 
the speed of light, and 
the wavelength)
So the answer is that the wavelength of the light must be shortened to cause the emission of electrones.
C is correct. The work-force relation is given by W=F·d, where F is force vector, and d is the displacement vector. The dot is the dot product, which is a measure of how parallel the two vectors are. It can be restated as the product of two vector magnitudes times the cosine of the angle between them. Therefore work is a scalar, not a vector, since the dot product returns a scalar.
Explanation:
Gravity is the force of attraction between two objects. It depends upon the mass of the objects and the distance between the objects. Mathematically, the force of gravity is given by :
Where
G is the universal gravitational constant
are masses
d is the distance between two masses
So, statement (2) describes gravity "Gravity is the force of attraction between two objects; it is dependent upon the mass of the objects and the distance between the objects".
