Physics: Post your doubts here!

[nehaoscar]

Volume = 2000 * 10 = 20000
Mass = 20000 * 1.3 = 26000
KE = 0.5 * 26000 * 10^2 = 1300J
efficiency is 50% so answer is 650KW


It is projectile motion, so the path is parabolic.

But it won't form a circle? Like the parabolic path is not part of any circle?

 

[DaniyalK]

But it won't form a circle? Like the parabolic path is not part of any circle?

afaik, a parabola can't be circle shaped.

 

[awesomaholic101]

Can someone please explain. This question pls

http://physics-ref.blogspot.in/2015/04/physics-9702-doubts-help-page-105.html
check the link : Q.538

 

[Xtreamer]

Why will the line NOT be part of a circle?

It can NEVER form a circle...usually thats the the wrong choice in MCQ

 

[awesomaholic101]

It can NEVER form a circle...usually thats the the wrong choice in MCQ

... and the path of the electrons after it exists the feild is always a straight line which is the tangent to the parabola formed before its exit

 

[BhaiArshad]

Why not B?

 

[princess Anu]

I don't get whats wrong in B &D?

 

[nehaoscar]

Can someone please give me the values for the wavelengths and frequencies of all the electromagnetic radiations please???

 

[DaniyalK]

Why not B?

You are subtracting 2 readings so the error is (1/60) * 100

 

[princess Anu]

Why not B?

is it D?
The uncertainty in temp rise is O.5*2 because Rise = final -initial temp.. so the uncertainty in both the temp is added to give a final uncertainty of 1.

 

[Xtreamer]

is it D?
The uncertainty in temp rise is O.5*2 because Rise = final -initial temp.. so the uncertainty in both the temp is added to give a final uncertainty of 1.

yes i think so

 

[princess Anu]

Can u help me with this.? why is B wrong

yes i think so

 

[awesomaholic101]

Why not B?

(0.5*2/60)*100 = 1.7%

 

[Xtreamer]

Can someone please give me the values for the wavelengths and frequencies of all the electromagnetic radiations please???

Just remember the wavelengths then work out the frequencies by v=f(lambda) where v = 3 * 10 power 8 ( value is given in data booklet)
The wavelengths

Gamma 1o power -14 to -10
X rays power -13 to -8
UV power -8 to -7
Visible power -7
Micro power -7 to -3
Radio power -1 to 6

 

[BhaiArshad]

 

[princess Anu]

Why is C incorrect? external forces cancelling out means 0 resultant force right ??

 

[Ahmed Aqdam]

At X it is at height 5 m as 1/0.2=5
At Y height will be 5.3 m so GPE will be 5.3*0.2=1.06 J

 

[Ahmed Aqdam]

Why is C incorrect? external forces cancelling out means 0 resultant force rightView attachment 54946 ??

There could be a change in mass.

 

[Xtreamer]

Can u help me with this.? why is B wrong

What is the Answer is it D?

 

[BhaiArshad]

is it D?
The uncertainty in temp rise is O.5*2 because Rise = final -initial temp.. so the uncertainty in both the temp is added to give a final uncertainty of 1.

Yes but it is like this. Rise = Final - 40.
Why is 40 counted in this?