A wind with speed 40 m/s blows parallel to the roof of a house. The area of the roof is 250 m². Assuming that the pressure inside the house is atmospheric pressure, the force exerted by the wind on the roof and the direction of the force will be $$({\rho _{air}} = 1.2kg/{m^3})$$

On observing light from three different starts P, Q and R, it was found that intensity of violet colour is maximum in the spectrum of P, the intensity of green colour is maximum in the spectrum of R and the intensity of red colour is maximum in the spectrum of Q. If T_P, T_Q and T_R are the respective absolute temperatures of P, Q and R, then it can be conclued from the above observations that

The approximate depth of an ocean is 2700 m. The compressiblity of water is 45.4 $$ \times $$ 10^$$-$$11 Pa^$$-$$1 and density of water is 10³ kg/m³. What fractional compression of water will be obtained at the bottom of the ocean?

Copper of fixed volume V is drawn into wire of length $$l$$. When this wire is subjected to a constant force F, the extension produced in the wire is $$\Delta $$$$l$$. Which of the following graphs is a straight line ?