MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: R

There are no items in this cart.
Continue Shopping
Menu
Get instant 20% OFF on Online Material.
coupon code: MOB20 | View Course list

  • Complete Physics Course - Class 11
  • OFFERED PRICE: R 2,800
  • View Details
Get extra R 2,800 off
USE CODE: chait6

				   

1)a radioactive material has mean life 1620 yrs and 540 yrs for alpha-emission and beta- emission respectively.The time in which half of the material remains undecayed emitting both these radiations is________


2)mass of 2 curie uranium(234)is_______


3)Half life of radium is 1620yrs &its atomic weight =226kg/kilomole.No. of atoms that will decay from 1 gm. of sample per second will be _________


4)Ratio of momenta of an electron of mass me and an alpha particle of mass ma which are accelerated from rest by a potential difference of 250V is_______

7 years ago

Share

Answers : (2)

										

Answer to qsn no 4:


the kinetic energy = qV. In either case the q has same numerical value.( since an alpha particle is a hydrogen nucleus = +1 unit charge wheras an electron  has -1 unit charge)


so, the kinetic energy has same value


hence p^2/2m is the same. therefore,  (p1/p2)^2 = (m1/m2). the required ratio is therefore sqrt of (me/ma)

7 years ago
										

nswer to qsn no 3:


226g/mol => 226 g of the material will have avagadros number of atoms. hence, 1 g will have A/226 atoms. Now in this case, this is the starting amterial ie N0 . And it is a first order eaction.


hence, N = N0e-kt


-dN/dt = kN0e-kt. U know K from half life and if u adjust the units in terms of seconds ie. 1620x365x24x60x60 sec,then put t=0 in the above eqn. You will get the rate of decomposition in terms of atoms/sec for initial conc. this is the answer u seek

7 years ago

Post Your Answer

Other Related Questions on Modern Physics

A Ball is thrown verticall upward with a velocity ‘u’ from the balloon descending with a constant velocity ‘v’. The ball will pass by the balloon after time ?
 
 
Dear Ranjeet Kumar, How can you Take Displacement of ball be “vt” . It should be “vt+1/2gt 2 . Its right Answer is 2(u+v)/g. I know the answer. But dont know how to solve.
 
Kuldeep Pal 4 months ago
 
The question needs the basic understanding of motion to solve it. considering the downward direction to be +ve and taking ground as the reference point, we have : initial velocity of ball...
 
RANJEET KUMAR 4 months ago
 
Dear Kuldeep, the velocity u of the ball must be with respect to the balloon. Then, taking the upward direction as positive we have: Initial velocity of the ball = u Constant velocity of the...
 
Raman Mishra 4 months ago
Q)km / h 2 is a unit of (a) velocity (b) speed (c) acceleration (d) distance
 
 
hi naveen km/h2.it is in the form of m/s2, so m/s2 is the unit of acceleration therefore answer is (c)acceleration
 
venkata ramana one month ago
 
naveen it is a simple question. we have to convert km/h^2 it gives m/sec^2. so m/sec^2 is the unit of acceleration.the answer is (c)
 
badugu vijaya kumar yadav one month ago
 
HI NAVVEN THESE ARE UNITS OF ACCELERATION SO CORRECT ANSWER IS C] ACCELERATION THANKS KEEP POSTING YOUR DOUBTS :}
 
SAHIL one month ago
In physics,is v-t graph possible for the above specified image??
 
 
Hii this is not possible as at same point of time it is showing two positions which is kind of impossible ,Hence it is not possible to draw v-t curve .
  img
Sourabh Singh 3 months ago
 
Quantum physics is based on probabilistic approach. We define a region where probability of finding a particle is maximum. But we cant exactly define its position and momentum. Hope you...
 
Gundeep Singh 3 months ago
 
But in quantum physics,is it possible??
 
Rahul 3 months ago
what is work energy thereom...................................?
 
 
The work-energy theorem is a generalized description of motion which states that work done by the sum of all forces acting on an object is equal to change in that object’s kinetic energy....
 
dolly bhatia one month ago
 
The work W done by the net force on a particle equals the change in the particle`s kinetic energy KE: W = Δ K E = 1 2 m v f 2 − 1 2 m v i 2 . The work-energy theorem can be derived from...
 
Sushmit Trivedi one month ago
 
For any net force acting on a particle moving along any curvilinear path, it can be demonstrated that its work equals the change in the kinetic energy of the particle by a simple derivation...
 
rahul kushwaha 3 months ago
The cieling of long hall is 25 m high What is the maximum horizontal distance that a ball thrown with a speed of 40 ms can go without hitting the ceiling of wall? Plz explain with a DIAGRAM
 
 
Let the angle of throwing be Q with respect to the ground So, the range is R = 40*cosQ*t where t = time taken reach ground. Now, we know the time taken to reach the top of its flight is half...
 
Tapas Khanda 5 months ago
 
Let the angle of throwing be Q with respect to the ground So, the range is R = 30*cosQ*t where t = time taken reach ground. Now, we know the time taken to reach the top of its flight is half...
 
Tapas Khanda 5 months ago
 
Diagram is not required to solve this question. You can directly use the formula to find range : R = (v^2/g)*sin2Q Maximum height reached, H = v^2*sin^2Q/2g So, 25 = 40^2*sin^2Q/(2*9.8) So,...
 
Tapas Khanda 5 months ago
What harmfull gases are produced when we burn plastics? And can we burn plastics?
 
 
I`m doing a project, can someone help me, How to reduce those toxic contents when plantic are burnt Like sulphur, nitrogen etc
 
2017 years ago
View all Questions »

  • Complete Physics Course - Class 12
  • OFFERED PRICE: R 2,600
  • View Details
Get extra R 2,600 off
USE CODE: chait6

  • Complete Physics Course - Class 11
  • OFFERED PRICE: R 2,800
  • View Details

Get extra R 2,800 off
USE CODE: chait6

More Questions On Modern Physics

Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!!
Click Here for details