From the top of a building 9 m high, water drops are falling at equal intervals of time, such that when the first drop reaches the ground,

D)1/3rd of the country is pumping out more ground water than what goes in recharge

Given: s = 4200 J kg-1 °C-1, h = 200 m To find: Difference in temperatures (∆T) Formulae: (i) Q = ms∆T (ii) P.E. = mgh Calculation: From formulae (j) and (ii) When water falls from top...

 C) \(\cfrac{3h}4\)

B) height of the tower

The Capacitance of big drop will be 20μF We have, Volume of  big drop = 64 times the volume of small drop or 4/3 π.R3 = 64 x 4/3 π.r3 Or  R = 4r Now,...

C) Both (i) & (iv)

Correct option is C) oxygen

Correct option is (D) 3 Distance covered by car by travelling 60 kmph in 4 hours = speed \(\times\) time \(=60\times4\) = 240 km When car travels at 80 kmph then time by the car \(=\frac{Distance}{Speed}\) \(=\frac{240}{80}\) =...

a) Zero net force. The rain drop is falling with a constant speed. Hence, it acceleration is zero. As per Newton’s second law of motion, the net force acting on the rain...

Rainwater harvesting.