Answer with Explanation:
We are given that
Resistance of solenoid,R=4.3 ohm
Magnetic field,B=
Current,I=4.6 A
Diameter of wire,d=0.5 mm=
Radius of wire,r=

Radius of solenoid,r'=1 cm=

Resistivity of copper,
We know that

Where 
Using the formula


Number of turns of wire=
Number of turns of wire=
Hence, the number of turns of the solenoid,N=799
Magnetic field in solenoid,B=






Length of solenoid=12.5 cm
1m=100 cm
Answer:
7.98 m
Explanation:
In the given question,
distance above surface= 2 m
Distance penny from person = 8 m
Since the swimming pool is filled with water and atmosphere has air therefore the refractive index phenomenon will occur.
The refractive index of water: air is 4/3 (1.33).
Using the formula, 4/3 = real depth, apparent depth
real depth= 4/3 x apparent depth
Now, calculating apparent depth = 8 - 2
= 6 m
therefore, real depth = 4/3 x apparent depth
= 1.33 x 6
= 7.98
thus, 7.98 m is the real depth of water.
Answer:
B = 7.6 T direction of + x
Explanation:
For the proton beam to continue in the same direction the electric and magnetic forces must be equal
= 0
= F_{e}
Fm = q E
The electric force is in the direction of the electric field because it is the charge of the positive proton, the electric force goes in the direction of –y, therefore, the magnetic force cancels this force must go in the direction of + y
The magnetic force is
F_{m} = q v x B = q v B sin θ
θ = 90
B = q E / q v
B = E / v
B = 800/105
B = 7.6 T
To find the direction of the magnetic field we use the right hand rule, the thumb goes in the direction of the proton velocity, the fingers extended in the direction of the magnetic field and the palm is the direction of force, for a positive charge.
Thumb goes in the direction of the + z axis
Palm in the direction of +y
Fingers point in the direction of + x
Answer:
harmful effects
1. that will cause air pollution
2. that will destroy our earth