The average power required to lift a $100 \ kg$ mass through a height of $50 \ m$ in approximately $50 \ s$ would be ............. $J/s$.

Two bodies of mass $m_1$ and $m_2$ $(m_2 > m_1)$ are connected by a light inextensible string which passes through a smooth fixed pulley. The instantaneous power delivered by an external agent to pull $m_1$ with constant velocity $v$ is

$A$ car of mass $m$ is driven with constant power $P$. If it starts from rest,find its velocity $v$ after traveling a distance $x$.

Water falls from a dam at a height of $550 \ m$ onto a turbine at a height of $50 \ m$ at a rate of $2000 \ kg$ per second. If the efficiency of the turbine is $80\%$,the power generated is ............. $MW$.

Water is falling on the blades of a turbine from a height of $25 \ m$. $3 \times 10^3 \ kg$ of water pours on the blade per minute. If the whole of energy is transferred to the turbine,the power delivered is: (in $W$)

$A$ particle is acted upon by a constant power. Then,which of the following physical quantity remains constant?