Physics

Choose the correct option:

What should be the height of transmitting antenna and the population covered if the televition telecast is to cover a radius of 150 km? The average population density around the tower is 200 / km² and the value of R_e = 6.5 * 10⁶ m.

A bullet of '4g' mass is fired from a gun of mass 4kg. If the bullet moves with the muzzle speed of 50 ms^-1, the impulse imparted to the gun velocity of recoil of gun are:

Statement I : The ferromagnetic property depends on temperature. At high temperature, ferromagnet becomes paramagnet.

Statement II : At high temperature, the domain wall are of a ferromagnetic substance increases.

In the light of the above statements, choose the most appropriate answer from the options given below:

T₀ is the time period of a simple pendulum at a place. If the length of the pendulum is reduced to $\frac{1}{16}$  times of its initial value, the modified time period is:

A porter lifts a heavy suitcase of mass 80kg and at the destination lowers it down by a distance of 80 cm with a constant velocity. Calculate the work done by the porter in lowering the suitcase.

(take g = 9.8 ms^-2)

Consider a situation in which reverse biased current of a particular P – N junction increase when it is exposed to a light of wavelength $\le$  621 nm. During this process, enhancement in carrier concentration takes place due to generation of hole – electron pairs. The value of band gap is nearly.

In a circuit consisting of a capacitance and a generator with alternating emf E_g = $E_{g_0}$ sin $\omega t$ , V_C and I_C are the voltage and current. Correct phase diagram for such circuit is:

Intensity of sunlight is observed as 0.092 Wm^-2 at a point in free space. What will be the peak value of magnetic field at that point?

$\left({\epsilon }_0=8.85*10^{-12}{C}^2{N}^{-1}{m}^{-2}\right)$  

A nucleus with number 184 initially at rest emits an a-particle. If the Q value of the reaction is 5.5 MeV, calculate the kinetic energy of the  α - particle.