Which of the following unit is related to sound frequency?
a) Hertz
b) Decibel
c) Second
d) Meter

Answer

A, B, C

Explanation

`v=velocity of car`
`=36 km/hr=10 m/sec`
`r=radius of circular path =50 m`
`mu=` mass of small body `
`=100 gj=0.1 kg `
`u=friction coefficient between plant & body
=0.58
a. The normal contact force exerted by the plant on the block
`N=(mv^2)/r`
`=0.1xx100/50=1/5=0.2N`
b. The plate is turned so the angle betwen the normal tothe plate and teh radius of the rod slolwly increases
`N=(mv^2)/rcostheta` .........i
`muN=(mv^2)/rsintheta` ........ii
putting value of N from i ltbr. `(mumv^2)/rcostheta=(mv^2)/rsintheta`
rarr mu=tantheta`
`rarr theta=tan^-1(0.58)=30^0`