Answer:
The width of the central bright fringe on the screen is observed to be unchanged is 
Explanation:
To solve the problem it is necessary to apply the concepts related to interference from two sources. Destructive interference produces the dark fringes. Dark fringes in the diffraction pattern of a single slit are found at angles θ for which

Where,
w = width
wavelength
m is an integer, m = 1, 2, 3...
We here know that as
as w are constant, then

We need to find
, then

Replacing with our values:


Therefore the width of the central bright fringe on the screen is observed to be unchanged is 
Answer:
6.88 m/s
Explanation:
The Conservation of Energy states that:
Initial Kinetic Energy + Initial Potential Energy = Final Kinetic Energy + Final Potential Energy
So we can write

We can cancel the common factor of
which leaves us with

Lets solve for 

Subtract
from both sides of the equation.

Multiply both sides of the equation by 2.

Simplify the left side.
Apply the distributive property.

Cancel the common factor of 2.

Take the square root of both sides of the equation to eliminate the exponent on the right side.

We are given
.
We can now solve for the final velocity.

Anything multiplied by 0 is 0.



Answer:
a) 
b) a = 5.59 m/s²
Explanation:
given,
total distance traveled by the car to stop is 56.9 m when speed of vehicle is 80 km/h or 80 × 0.278 = 22.24 m/s
total distance traveled by the car to stop is 25.7 m when speed of vehicle is 50.7 km/h or 50.7 × 0.278 = 14.09 m/s
using stopping distance formula
................(1)
..............(2)
on solving both the equation we get


a = 5.59 m/s²
now reaction time calculation

