All Mechanics DOUBTS HERE!!!

[Saladin]

Please post your M1 doubts here!!!!!

I do Edexcel M1.

[halosh92]

two particles P and Q of masses 3kg and 6kg respectively are attached to the ends of a  light inextensible string.
the string passes over a smooth fixed pulley . the system is released from rest with both masses a distance of 2m
above a horizontal floor. find how long it takes for particle Q to hit the floor.
assuming particle P does not reach the pulley find its greatest height above the floor

i got the time which is 1.11 but i cant get the distance.

[Saladin]

In 1 hour.

[halosh92]

could someone plzzz solve this??

[halosh92]

two particles P and Q of masses 1kg and 2kg respectively are hanging from the ends of  alight inextensible string which passes over  a smooth fixed pulley. the system is released from rest with both particles a distance 1.5m above a  floor. when the masses have been moving fir 0.5 s the string breaks. find the furthur time that elapses  before P hits the floor
 

[astarmathsandphysics]

For 2kg 2g-t=2a
For 1 kg t-g=a
Add there two equations g=3a so a=g/3
When string breaks particle falls under gravity so a=g

[astarmathsandphysics]

Height=1.5+0.5*g/3*0.5^2 then use this height with s=1/2at^2 to find find t

[halosh92]

Height=1.5+0.5*g/3*0.5^2 then use this height with s=1/2at^2 to find find t

how did u exactly get this?
0.5*g/3*0.5^2    and for s=1/2at^2  do we use 9.8 for the acceleration?
thx

[halosh92]

two particles A and B of masses 0.5kg and 0.7kg respectively are connected by a light inextensible string. particle A rests on a smooth horizontal table 1m from a fixed smooth pulley and B hangs freely 0.75m above the floor. the system is released from rest with the string taut. after 0.5s the string breaks.
find:
a) the distance the particles haved moved when the string broke
b) the velocity of the particles when the string breaks
c) the furthur time that elapses before A reaches the floor, given that the table is 0.9m high.


how to do part c ??

[Saladin]

can you please send the exact question paper. I need to see that.

[halosh92]

can you please send the exact question paper. I need to see that.

its from my textbook actually :S

[Khey [Rainbow]]

A large crate of mass 40kg lies at rest on rough horizontal ground. One end of the rope is attached to the crate and the rope makes an angle of 30 with ground as shown in the diagram. The tension of the rope is 150N and the crate is on the of moving along the plane.
By modelling the crate as a particle,
(a) Find the value of [mue], the cofficient of frction between the crate and the ground.
The rope remains at 30 degree to the ground but the tension init is increased to 200N.
(b) Find the acceleration of the crate.
 

[Saladin]

Solving now, please be pateint. Will take 40 minutes.

[Saladin]

two particles A and B of masses 0.5kg and 0.7kg respectively are connected by a light inextensible string. particle A rests on a smooth horizontal table 1m from a fixed smooth pulley and B hangs freely 0.75m above the floor. the system is released from rest with the string taut. after 0.5s the string breaks.
find:
a) the distance the particles haved moved when the string broke
b) the velocity of the particles when the string breaks
c) the furthur time that elapses before A reaches the floor, given that the table is 0.9m high.


how to do part c ??

u can also send me the book name and page number.

[halosh92]

u can also send me the book name and page number.

heinemann modular mechanics for edexcel AS and A level
pg113
q11