A baloon filled with helium rises against
gravity increasing its potential energy.
The speed of the baloon also increases
as it rises. How do you reconcile this
with the law of conservation of
mechanical energy? You can neglect
viscous drag of air and assume that
density of air is constant.
(∣m^2 −n^2 ∣,2mn,m^2 +n^2 ) is pythagorean
triplet for all m,n∈N. This can be
proved easily.Is the vice versa of
the statement is also true?
I-E
If for a,b,c∈N ,a^2 +b^2 =c^2 then there
exist m,n∈N such that m^2 +n^2 =c and
{a,b}={∣m^2 −n^2 ∣,2mn}
A rocket accelerates straight up by
ejecting gas downwards. In a small
time interval Δt, it ejects a gas of mass
Δm at a relative speed u. Calculate KE
of the entire system at t + Δt and t and
show that the device that ejects gas
does work = ((1/2))Δmu^2 in this time
interval (neglect gravity).
A particle of mass m strikes on ground
with angle of incidence 45°. If coefficient
of restitution, e = (1/(√2)) , find the velocity
after impact and angle of reflection.