A ball of mass 50 g is thrown upwards. It rises to a maximum height of 100 m. At what height its kinetic energy will be reduced to 70 % ?

Q: A ball of mass 50 g is thrown upwards. It rises to a maximum height of 100 m. At what height its kinetic energy will be reduced to 70 % ?

(a) 30 m

(b) 40 m

(c) 60 m

(d) 70 m

Ans: (a)