Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Manipal MET2014PhysicsLaws of Motion

The kinetic energy k of a particle moving along a circle of radius R depends on the distance covered. It is given as KE =a s^2 , where a is a constant. The force acting on the particle is

Options

  1. A2 a s^2 R
  2. B2 a s (1+ s^2 R^2 )^ 1 / 2
  3. C2 a ~s
  4. D2 a R^2 s

Correct answer

B. 2 a s (1+ s^2 R^2 )^ 1 / 2

Step-by-step solution

In non-uniform circular motion two forces will work on a particle F_c and F_t . So, the net force F_ Net = F_c^2+F_t^2 ...(i) Centripetal force F_c= m v^2 R = 2 a s^2 R ...(ii) [given 1 2 m v^2=a s^2 given] Again from 1 2 m v^2=a s^2 v^2= 2 a s^2 m v=s 2 a m Tangential acceleration a_t= d v d t = d v d s d s d t a_t= d d s [s 2 a m ] va_t=v 2 a m =s 2 a m 2 a m = 2 a s m and F_t=m a_t=2 a s ...(iii) Now, on substituting value of F_c and F_t in Eq. (i), we get F_ Net = ( 2 a s^2 R )^2+(2 a s)^2 =2 a s [1+ s^2 R^2 ]^

Practice Laws of Motion on Quantrex Academy →

More from Laws of Motion

A block of metal, of 25g mass moves down without acceleration when the plane is inclined at an angle of 30^ . When the inclination is increased by 30^ , find the downward accelerat 2026A man weighs 80 kg. He stands on a weighing scale in a lift which is moving upwards with a uniform acceleration of 6 m/s ^2 . What would be his weight in kg? ( g = 10 m/s ^2 ) 2026A mass M is hung with a light inextensible string as shown in figure. Find the tension of the horizontal string. 2026A horizontal force of 5 N is applied on a stationary body of mass 5 kg, which is initially at rest on a frictionless table. The change in kinetic energy of the body in 10 s is 2026The apparent weight of a girl of mass 30 kg when she is in a lift moving vertically upwards with an acceleration of 2 ~ms ⁻² is (Acceleration due to gravity =10 ~m ~s ⁻² ) 2025If a stone of mass 0.5 kg tied to one end of a wire is whirled in a circular path of radius 2 m with a speed 40 rev / min in a horizontal plane, then the tension in the wire is nea 2025If the breaking strength of a rope is 4 3 times the weight of a person, then the maximum acceleration with which the person can safely climb up the rope is (g - accelereation due t 2025A block of mass 2 kg is placed on a rough horizontal surface. If a horizontal force of 20 N acting on the block produces an acceleration of 7 ~m ~s ⁻² in it, then the coefficient o 2025 Full Laws of Motion list All Manipal MET PYQs