Answer:
Upward force on the boy will be 1024 N
Explanation:
We have given mass of the boy m = 80 kg
Acceleration due to gravity 
It is given that elevator is ascending with acceleration of 
So net acceleration on the boy = 9.8+3 = 12.8
( As the car elevator is moving ascending )
So upward force on the boy will be equal to F = m(g+a)
So 
So upward force on the boy will be 1024 N
let us consider that the two charges are of opposite nature .hence they will constitute a dipole .the separation distance is given as d and magnitude of each charges is q.
the mathematical formula for potential is 
for positive charges the potential is positive and is negative for negative charges.
the formula for electric field is given as-
for positive charges,the line filed is away from it and for negative charges the filed is towards it.
we know that on equitorial line the potential is zero.hence all the points situated on the line passing through centre of the dipole and perpendicular to the dipole length is zero.
here the net electric field due to the dipole can not be zero between the two charges,but we can find the points situated on the axial line but outside of charges where the electric field is zero.
now let the two charges of same nature.let these are positively charged.
here we can not find a point between two charges and on the line joining two charges where the potential is zero.
but at the mid point of the line joining two charges the filed is zero.
Answer:
Pretty sure its -4.8%
Explanation:
Others asked this question and got this as an answer.
Answer: Electromagnetic waves (Ultraviolet light, between 100 nm and 380 nm)
Explanation:
Solar cells work by the photoelectric effect, which consists of the emission of electrons (electric current) when light (electromagnetic waves) falls on a metal surface under certain conditions.
In this sense, the portion of the electromagnetic spectrum this cells use is Ultraviolet light (UV) from the Sun, whose wavelength is approximately between 100 nm and 380 nm.
It is important to note, this is a type of electromagnetic radiation that is not visible to the human eye.
Stepping on a can is a physical change because there is no chemistry behind this. Someone is physically breaking or deforming the can. There are no chemicals or anything touching the can. The foot smashing is physical.