Answer:
The magnetic field along x axis is

The magnetic field along y axis is zero.
The magnetic field along z axis is

Explanation:
Given that,
Length of the current element 
Current in y direction = 5.40 A
Point P located at 
The distance is


We need to calculate the magnetic field
Using Biot-savart law

Put the value into the formula

We need to calculate the value of 



Put the value into the formula of magnetic field


Hence, The magnetic field along x axis is

The magnetic field along y axis is zero.
The magnetic field along z axis is

Answer:
Number of photons travel through pin hole=
Explanation:
First we will calculate the energy of single photon using below formula:

Where :
h is plank's constant with value 
c is the speed of light whch is
λ is the wave length = 532nm

E=
J
Number of photons emitted per second:

Number of photons emitted per second=
=
Where:
A-hole is area of hole
A-beam is area of beam
d-hole is diameter of hole
d-beam is diameter if beam
=
=
=
Number of photons travel through pin hole=
Number of photons travel through pin hole=
Answer:
0.456033049
Explanation:
where N=mg hence
where m is mass of object, g is acceleration due to gravity whose value is taken as
,
is the coefficient of static friction and F is the applied force.
Making
the subject we obtain
and substituting m for 38 Kg, g for
and 170 N for F we obtain

Therefore, the coefficient of static friction is 0.456033049