Mathematics: Post your doubts here!

[ShoaibMallick]

Assalamualaikum please help me in this question
A lift starting from rest moves downwards with constant acceleration.It covers a distance 's' in time 't',where s =1/6gt^2 .A box of mass 'm' is on the floor of the lift.Find,in terms of 'm' and 'g' , an expression for the normal contact force on the box from the lift.

 

[celoth]

Assalamualaikum please help me in this question
A lift starting from rest moves downwards with constant acceleration.It covers a distance 's' in time 't',where s =1/6gt^2 .A box of mass 'm' is on the floor of the lift.Find,in terms of 'm' and 'g' , an expression for the normal contact force on the box from the lift.

the answer is it 2mg/3 ??

 

[shanky631]

doubt in the second part of this question.

 

[shanky631]

plz help me in this question also



the ans for the first part is 3.5
and for the second part is 0.25(5+e^-6)

 

[nightrider1993]

Hey thanks for replying. but unfortunately i can't see anything, its tiny Can you try to post a better shot?

Try saving the picture on ur computer and then magnify it

 

[leadingguy]

Assalamualaikum please help me in this question
A lift starting from rest moves downwards with constant acceleration.It covers a distance 's' in time 't',where s =1/6gt^2 .A box of mass 'm' is on the floor of the lift.Find,in terms of 'm' and 'g' , an expression for the normal contact force on the box from the lift.

If u get to know the ans post here and mention me in the comment. will be great of you. thanks

 

[leadingguy]

doubt in the second part of this question.
View attachment 15104

atleast write the correct ans. for the first part so we can carry on for the next part. thankyou.

 

[leadingguy]

plz help me in this question also

View attachment 15105

the ans for the first part is 3.5
and for the second part is 0.25(5+e^-6)

 

[leadingguy]

Anyone in Pakistan giving maths A-level this oct/nov?? if so please let me know. thanks

 

[parthrocks]

Anyone in Pakistan giving maths A-level this oct/nov?? if so please let me know. thanks

Not from pakistan m from india!!giving oct/nov 2012 exams!!!

 

[leadingguy]

Not from pakistan m from india!!giving oct/nov 2012 exams!!!

which componenets??? and any one from Pakistan?? and yes what are the dates??? of paper??

 

[Bilal Khan]

which componenets??? and any one from Pakistan?? and yes what are the dates??? of paper??

i am from pakistan.

 

[leadingguy]

i am from pakistan.

so u appearing a level maths this oct.nov.?? which components??? and when are the dates??? will be kind if u reply again.

 

[parthrocks]

which componenets??? and any one from Pakistan?? and yes what are the dates??? of paper??

M giving paper 3 and paper 7(stats) and also ya the dates are
we have p3 on 30th oct and paper 7 on 7th november!!!what about u???u complted all of the as and a2 course???right??

 

[shanky631]

thanks leadingguy. you have been very helpful.

 

[ShoaibMallick]

If u get to know the ans post here and mention me in the comment. will be great of you. thanks

2/3mg is the answer i want to know the method of solving this question thanks

 

[ShoaibMallick]

the answer is it 2mg/3 ??

yes the answer is the same but i want to know the method

 

[Amy Bloom]

Ok thanks

Try saving the picture on ur computer and then magnify it

 

[celoth]

yes the answer is the same but i want to know the method

is like this:

s = (1/6)gt^2 (given from question)
s = ut+(1/2)at^2 (what we normally know)
since it start at rest, therefore u=0,

s = (1/2)at^2 , compare with the given s = (1/6)gt^2,
we will find that a = g/3

then the force acting on the box is:
mg-R=ma
R=mg-ma
R = mg - m(g/3)
R = (2mg)/3

 

[afrah]

hey i hve just started as- level....can anyone pls solve question 4B miscellenous excercise from the P1 book??? asap