Home
Class 12
PHYSICS
A particle of mass m is at rest at the o...

A particle of mass m is at rest at the origin at time t = 0.It is subjected to a force `F(t)=F_(0)e^(-bt)` in the x direction. Its speed v(t) is depicted by which of the following curves ?

A

B

C

D

Text Solution

Verified by Experts

The correct Answer is:
D

`F=ma=F_(0)e^(-bt)`
`(dv)/(dt)=(F_(0))/(m)e^(-bt)`
`underset(0)overset(v)int dv=(F_(0))/(m)underset(0)overset(t)int e^(-bt)dt=(F_(0))/(m)((e^(-bt))/(-b))_(0)^(t)`
`v=(F_(0))/(mb)(1-e^(-bt))`
So, correct choice is (d).
Promotional Banner

Topper's Solved these Questions

  • OSCILLATIONS

    MODERN PUBLICATION|Exercise RCQ|7 Videos
  • OSCILLATIONS

    MODERN PUBLICATION|Exercise MCQ (LEVEL-II)|62 Videos
  • MOCK TEST-3

    MODERN PUBLICATION|Exercise MCQs|49 Videos
  • PROPERTIES OF MATTER

    MODERN PUBLICATION|Exercise RECENT COMPETITIVE QUESTIONS|17 Videos

Similar Questions

Explore conceptually related problems

A particle of mass 'm' at rest is acted upon by a force 'P for a time 'r'. Its Kinetic energy after an interval 'r' is:

A body of mass m at rest is subjected to a constant force F for time. The kinetic energy at timet is given by :

A particle of mass 0.3 kg is subjected to a force F =- kx with k = 15 N//m . What will be its initial acceleration if it is released from a point 20 cm away from the origin?

If f(x) = int_(0)^(x) t sin t dt, then f'(x) is

One end of a string of length l is connected to a particle of mass m and the other to a small peg on a smooth horizontal table. If the particle moves in a circle with speed v the net force on the particle (directed towards the centre) is : (i) T, (ii) T - (mv^2)/(l) , (iii) T + (mv^2)/(l) , (iv) 0 T is the tension in the string. [Choose the correct alternative].

One end of a string of length 'l' is connected to a particle of mass m and the other to a small peg on a smooth horizontal table . If the particle moves in a circle with speed 'v', the net force on the particle (directed towards the centre ) is :(T is the tension in the string ).

At what speed is a particle moving if the mass is equal to three times its rest mass. Data m=3m_(0) , v = ?