1)Tom picks up 2 books from his bag on floor and places it on the desk.The mass of a book is 0.600kg. The desk is 0.9m high from the floor. If the acceleration due to gravity,g=10m/s^2,calculate the work done by the boy in lifting the book from the floor to the desk.
how?
W = mgh
(2 x 0 .6) x 10 x 0.9 = 10.8 J
i hope this is not some trick question, coz i'll be falling right into it.. lol..
Originally posted by purpledragon84:W = mgh
(2 x 0 .6) x 10 x 0.9 = 10.8 J
i hope this is not some trick question, coz i'll be falling right into it.. lol..
no la lol..u got correct :D
2) A mixture of volume is 1m^3 consists of 60% material P and 40% material Q. The density of P is 1000kg/m^3 and that og Q is 800kg/m^3. What is the mass of the mixture?
P is 60%.. 60% can be written and used as 0.6..
so 60% of 1m^3 is 0.6m^3
so mass contributed by P will be 0.6 x 1000 = 600kg
and for Q, 0.4 x 800 = 320kg..
total 920kg..
a proton with constant momentum <0,0,2.7e-19>kgm^-1 leaves the origin 10 second after accelerator experiemnt... what is the proton 2 ns later? momnetum update principal P=P + Fnet(delta T)
buay hiao..
lol...