Work and Energy...

A body is falling a height $$h$$. After it has fallen a height $$\dfrac{h}{2}$$. it will possess

The height of the water dam in the hydroelectric power station is $$20$$ m. How much water. in $$1$$ second, should fall on turbine, so that $$1$$ MW power is generated ?($$g = 10m/s^2$$)

The engine of a car of mass $$1500$$ kg. keeps the car moving with constant velocity $$v=5\ m/s$$. If frictional force is $$1000$$ N, the power of the engine is...

Four alternatives are given to each of the following incomplete statements/questions. Choose the right answer:
Which of the following object has higher potential energy?

Work done is equal to?

Is the work required to be done by an external force on an object on a frictionless, horizontal surface to accelerate it from a speed $$v$$ to a speed $$2v$$.

At the start of the free-fall of an object from height $$h$$, the potential energy is _____ and kinetic energy is _____.

Bullet $$2$$ has twice the mass of bullet $$1$$. Both are fired so that they have the same speed. If the kinetic energy of bullet $$1$$ is $$K$$, is the kinetic energy of bullet $$2$$

We can explain free-fall of an object on the basis of?

Whenever energy gets transformed, the total energy_______.