If the intensity of an X-ray becomes `(I_(0))/(2)` from `I_(0)` after travelling 2.0 cm inside a target, then its intesity after travelling a distance of 4 cm will be

If the intensity of an X-ray becomes I_(0)/3 from I_(0) after travelling 3.5cm inside a target then its intensity after travelling next 7 cm will be

If the intensity of an X-ray becomes I_(0)/3 from I_(0) after travelling 3.5cm inside a target then its intensity after travelling next 7 cm will be

. A bullet moving with a velocity of 200 cm / s penetrates a wooden block and comes to rest after traversing 4 cm inside it. What velocity is needed for travelling distance of 9cm in same block

The intensity of gamma - from a source (I_(0)) reduces to I_(0)//8 after passing through 48 mm thick sheet of lead. The thicness of the sheet for obtaining intensity equal to I_(0) / 2 will be-

Two sinusoidal plane waves of same frequency having intensities I_(0) and 4I_(0) are travelling in the same direction. The resultant intensity at a point at which waves meet with a phase difference of zero radian is

The intensity of X-rays decreases exponentially according to the law I=I_(0)e^(-mux) , where I^(0) is the initial intensity of X-rays and I is the intensity after it penetrates a distance x through lead. If mu be the absorption coefficient, then find the dimensional formula for mu .

If I_(0) and I_(a) denote intensities of incident and absorbed X-rays, then-

A point source with luminous intensity I_(0) = 100 cd is positioned at a distance s = 20.0 cm from the crest of a concave mirror with focal length f = 25.0 cm . Find the luminous intensity of the reflected ray if the reflection coefficient of the mirror is rho = 0.80 .