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write the method to synthesis of phenol?

A stream of water flowing horizontally with a speed of 15 m/s pushes out of a tube of cross-sectional area 10-2 m2 and hits at a vertical wall nearby. What is the force exefrted on the wall by the impact of water, assuming that it does not rebound?

A helicopter of mass 1000 kg rises with a vertical acceleration of 15 ms-2. The crew and the passengers weigh 300 kg. Give the magnitude and direction of

(a) force on the floor by the crew and passengers,

(b) the action of the rotor of the helicopter on surrounding air

(c) force on the helicopter due to the surrounding air

A stone of mass m tied to the end of a string is revolving in a vertical circle of radius R. The net force at the lowest and highest points of the circle directed vertically downwards are: (choose the correct alternative).

T1 and v1 denote the tension and speed at the lowest point. T2 and v2 denote corresponding values at the highest point.

Explain why

(a) a horse cannot pull a cart and run in empty space,

(b) passengers are thrown forward from their seats when a speeding bus stops suddenly,

(c) it is easier to pull a lawnmower than to push it,

(d) a cricketer moves his hands backwards while holding a catch

A stone of mass 0.25 kg tied to the end of a string is whirled round in a circle of radius 1.5 m with a speed of 40 rev./min in a horizontal plane. What is the tension in the string? What is the maximum speed with which the stone can be whirled around if the string can withstand a maximum tension of 200 N?

 A simple pendulum of length l and having a bob of mass M is suspended in a car. The car is moving on a circular track of radius R with a uniform speed v. If the pendulum makes small oscillations in a radial direction about its equilibrium position, what will be its time period?

The marked price of an article is Rs 80 and it is sold at Rs 76, then the discount rate is:

(a) 5% (b) 95% (c) 10% (d) appx. 11%

Shyama purchases a scooter costing Rs 36,450 and the rate of sales tax is 9%, then the total amount paid by her is:

(a) Rs 36,490.50 (b) Rs 39,730.50 (c) Rs 36,454.50 (d) Rs 33,169.50