We use the formula v=ir where I is current, v is voltage, and r is resistance, we get that r=12/100 which is answer choice A
Answer
given,
mass of steel ball, M = 4.3 kg
length of the chord, L = 6.5 m
mass of the block, m = 4.3 Kg
coefficient of friction, μ = 0.9
acceleration due to gravity, g = 9.81 m/s²
here the potential energy of the bob is converted into kinetic energy



v = 11.29 m/s
As the collision is elastic the velocity of the block is same as that of bob.
now,
work done by the friction force = kinetic energy of the block




d = 7.23 m
the distance traveled by the block will be equal to 7.23 m.
Answer:

Explanation:
The work function of the metal corresponds to the minimum energy needed to extract a photoelectron from the metal. In this case, it is:

So, the energy of the incoming photon hitting on the metal must be at least equal to this value.
The energy of a photon is given by

where
h is the Planck's constant
c is the speed of light
is the wavelength of the photon
Using
and solving for
, we find the maximum wavelength of the radiation that will eject electrons from the metal:

And since
1 angstrom = 
The wavelength in angstroms is

The beats are actually two new sounds.
Their frequencies are (the sum of the original two frequencies) and (the difference of the original two frequencies).
The existence of the beats is the result of the difference in the frequencies of the original two sounds. <em> (b)</em>