Answer:
2653 turns
Explanation:
We are given that
Diameter,d=2 cm
Length of magnet,l=8 cm=
1m=100 cm
Magnetic field,B=0.1 T
Current,I=2.4 A
We are given that
Magnetic field of solenoid and magnetic are same and size of both solenoid and magnetic are also same.
Length of solenoid=
Magnetic field of solenoid

Using the formula

Where 

Answer:
Speed of the car 1 =
Speed of the car 2 =
Explanation:
Given:
Mass of the car 1 , M₁ = Twice the mass of car 2(M₂)
mathematically,
M₁ = 2M₂
Kinetic Energy of the car 1 = Half the kinetic energy of the car 2
KE₁ = 0.5 KE₂
Now, the kinetic energy for a body is given as

where,
m = mass of the body
v = velocity of the body
thus,

or

or

or

or

or
.................(1)
also,

or

or

or

or

or

or

or

or

and, from equation (1)

Hence,
Speed of car 1 =
Speed of car 2 =
Answer:
If the frequency of the source is increased the current in the circuit will decrease.
Explanation:
The current through the circuit is given as;

Where;
V is the voltage in the AC circuit
Z is the impedance

Where;
R is the resistance
is the inductive reactance
= ωL = 2πfL
where;
L is the inductance
f is the frequency of the source
Finally, the current in the circuit is given as;

From the equation above, an increase in frequency (f) will cause a decrease in current (I).
Therefore, If the frequency of the source is increased the current in the circuit will decrease.
A steel piano wire, of length 1.150 m and mass of 4.80 g is stretched under a tension of 580.0 N.the speed of transverse waves on the wire would be 372.77 m/s
<h3>What is a sound wave?</h3>
It is a particular variety of mechanical waves made up of the disruption brought on by the movements of the energy. In an elastic medium like the air, a sound wave travels through compression and rarefaction.
For calculating the wave velocity of the sound waves generated from the piano can be calculated by the formula
V= √F/μ
where v is the wave velocity of the wave travel on the string
F is the tension in the string of piano
μ is the mass per unit length of the string
As given in question a steel piano wire, of length 1.150 m and mass of 4.80 g is stretched under a tension of 580.0 N.
The μ is the mass per unit length of the string would be
μ = 4.80/(1.150×1000)
μ = 0.0041739 kg/m
By substituting the respective values of the tension on the string and the density(mass per unit length) in the above formula of the wave velocity
V= √F/μ
V=√(580/0.0041739)
V = 372.77 m/s
Thus, the speed of transverse waves on the wire comes out to be 372.77 m/s
Learn more about sound waves from here
brainly.com/question/11797560
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