A uniform disc of mass 100 g has a diameter of 10 cm. Calculate the total energy of the disc when rolling along a horizontal table with a velocity of 20 cm s^(-1). (take the surface of table as reference).

A uniform disc of mass 100 g has a diameter of 10 cm. Calculate the to

1.	A uniform disc of mass 100 g has a diameter of 10 cm. Calculate the total energy of the disc when rolling along a horizontal table with a velocity of 20 cm s^(-1). (take the surface of table as reference).
Answer» Solution :`m=100, g=0.1 KG,` DIA=10cm RADIUS =5cm=0.05m, v`=20cms^(-1)implies0.2ms^(-1)` Total ENERYG `=1/2 I omega^(2)+1/2mv^(2)` Potential K.E`=1/2 I omega^(2)=1/2xx(MR^(2))/2xxomega^(2)` `( :' omega v/r=0.2/0.05=4"rad"s^(-1))` `=1/2xx(0.1xx(0.05)^(2))/2xx4^(2)` `=0.001`............1 K.E `=1/2mv^(2)=1/2xx0.1xx0.2xx0.2` `[ :' h="dia"=10cm]` `=0.5xx0.1xx0.2xx0.2` `=0.0022`.........2 `1+2implies` Total energy `=0.001+0.002` `=0.003J`