Answer:
<h2>
16,931 turns</h2>
Explanation:
The magnetic field produced is expressed using the formula

B is the magnetic field = 0.30T
I is the current produced in the coil = 4.5A
is the magnetic permittivity in vacuum = 1.26*10^-6Tm/A
L is the length of the solenoid = 32 cm = 0.32 m
N is the number of turns in the solenoid.
Making N the subject of the formula from the equation above;


Substituting the give values to get N;

The number of turns the solenoid must have is approximately 16,931 turns
Answer:
Detailed explanation:
Density of water=1000kg/m³
Hence mass of water displaced is:
m=d×v
=1000kg/m³×(4.3×10^-3)m³ (volume of water displaced converted to L)
=4.3 kg of water
Hence, mass of football is also 4.3 kg(Archimedes principle)
Thus density of football
=mass÷volume
substitute the mass and volume and solve.
hope this helps
The energy of an electron as it is ejected from the atom can be calculated from the product of the Planck's constant and the frequency of the light energy. We can calculate the wavelength from the frequency we can calculate. We do as follows:
E = hv
4.41 x 10-19 = 6.62607004 × 10<span>-34 (v)
v = 6.66x10^14 /s
wavelength = speed of light / frequency
</span>
wavelength = 3x10^8 / 6.66x10^14
wavelength = 4.51x10^-7 m = 450.75 nm
Answer:
Explanation:
Let after time t , Tina catches up David .
Distance travelled by them are equal ,
Distance travelled by Tina
s = ut + 1/2 a t²
= .5 x 2.10 t²
= 1.05 t²
Distance travelled by David
= 30 t ( because of uniform velocity )
1.05 t² = 30t
t = 28.57 s
Distance travelled by Tina
= 1/2 a t²
= .5 x 2.10 x 28.57²
= 857 m approx.
Current.A moving charge is an object that changes position to one particular obsever.