Home › CBSE Class 9 › physics › c9potentialconservation › Per NCERT, why does a REAL pendulum eventually s…
Per NCERT, why does a REAL pendulum eventually slow down and stop — even though conservation of mechanical energy says it should oscillate forever?
AMechanical energy isn't really conserved
BGravity weakens with each swing
CFriction at the support and air resistance gradually convert mechanical energy into heat, removing energy from the pendulum
DThe pendulum gets too tired
Answer & Solution
Correct answer: C. Friction at the support and air resistance gradually convert mechanical energy into heat, removing energy from the pendulum
Per NCERT, real pendulums lose energy to friction + air resistance — the mechanical energy decreases over time. The other options misstate.
Related questions
Per NCERT, when a ball is in FREE FALL from height h, at what point during the fall is itsPer NCERT Activity 7.2 (the simple pendulum), why does the pendulum bob REACH ALMOST THE SPer NCERT Example 7.8, what is the velocity of a child at the BOTTOM of a frictionless sliPer NCERT, an object falling FREELY from height h (released from rest) — what is the velocPer NCERT, the CONSERVATION OF MECHANICAL ENERGY principle states which fact?Per NCERT, MECHANICAL ENERGY is defined as which combination?Per NCERT Activity 7.1 (heavy ball dropped onto sand from different heights), how does thePer NCERT Example 7.7, what is the PE of a 200 g cricket ball at a height of 10 m (taking