<span>Since there is no friction, conservation of energy gives change in energy is zero
Change in energy = 0
Change in KE + Change in PE = 0
1/2 x m x (vf^2 - vi^2) + m x g x (hf-hi) = 0
1/2 x (vf^2 - vi^2) + g x (hf-hi) = 0
(vf^2 - vi^2) = 2 x g x (hi - hf)
Since it starts from rest vi = 0
Vf = squareroot of (2 x g x (hi - hf))
For h1, no hf
Vf = squareroot of (2 x g x (hi - hf))
Vf = squareroot of (2 x 9.81 x 30)
Vf = squareroot of 588.6
Vf = 24.26
For h2
Vf = squareroot of (2 x 9.81 x (30 – 12))
Vf = squareroot of (9.81 x 36)
Vf = squareroot of 353.16
Vf = 18.79
For h3
Vf = squareroot of (2 x 9.81 x (30 – 20))
Vf = squareroot of (20 x 9.81)
Vf = 18.79</span>
Answer:
0.18216 T
Explanation:
N = Number of turns = 219
A = Area = 
r = Radius = 1 cm
= Angular speed = 
Maximum emf is given by

The strength of the magnetic field is 0.18216 T
Answer:
C
Explanation:
hope for help ....im expert
Archimedes principle states
that
F1 / A1 = F2 / A2
F2 = (A2 / A1) * F1
Also, formula for the force is
F = mg. Formula for the area of the cylinder is A = πr^2, therefore we get
F2 = (πr2^2 / πr1^2) * mg
Since the diameter of the
cylinders are 2 cm and 24 cm, r1 = 12 and r2 = 1.
Substituting the values to the
derived equation, we get
F2 = (π 1^2 / π 12^2) * 2400 * 9.8
F2 = 163.3333 N
<span> </span>
Answer:
0.203 micro meter
Explanation:
for destructive interference that appearsblack, use the formula
2 t = m λ / u (where m = 0 1 2 3 ... is order of minima)
where t = tickness,
u is the ref index = 1.32
Wavelenth λ = 535×10^-9 meter
for t (minimum) m = 1 (as m=0 is ruled out as t>0)
t = 1× 535×10^-9/2×1.32
t (min) = 202.65×10^-9 meter
OR
t (min) = 0.203×10^-6 meter = 0.203 micro meter