This is a Fraunhofer single slit experiment, where the light passing through the slit produces an interference pattern on the screen, and where the dark bands (minima of diffraction) are located at a distance of

from the center of the pattern. In the formula, m is the order of the minimum,

the wavelenght,

the distance of the screen from the slit and

the width of the slit.
In our problem, the distance of the first-order band (m=1) is

. The distance of the screen is D=86 cm while the wavelength is

. Using these data and re-arranging the formula, we can find a, the width of the slit:
Explanation:
Given
initial velocity(v_0)=1.72 m/s

using 
Where v=final velocity (Here v=0)
u=initial velocity(1.72 m/s)
a=acceleration 
s=distance traveled

s=0.214 m
(b)time taken to travel 0.214 m
v=u+at


t=0.249 s
(c)Speed of the block at bottom

Here u=0 as it started coming downward

v=1.72 m/s
Answer: the options to the questions are
a. 1.0 moles of N2
b.0.5 moles of New
c.0.2 moles of CO2
d.2 moles of He
Answer D
Explanation:
The average molecular speed v of gas is given by =√(8RT,/πM)
From the equation it can be seen that substance with lowest molar mass has the highest velocity has He is the answer
Answer:
A drop in voltage occurs
Explanation:
When electric current flows through a conduct, there are three basic electrical effects that occur to the conductor;
1. A magnetic field is set up around the conductor,
A magnetic field is formed around a conductor when current flows through it which makes it acts like a magnet. Application is used in electric bells.
2. Heat is generated, and
The heating effect of current is due to the conversion of some of the electrical energy that passes through the conductor, into heat energy. Application of heat effect include electric iron, microwave oven, electric bulb, hair straightener etc.
H = I²Rt
3. A drop in voltage occurs
Voltage drop is as a result of current passing through the impedance offers by the conductor or circuit elements. When current passes through a conductor, the resistance offers opposition to the flow of the electric current according to Ohm's law.