Force required to move a mass of 1 kg at rest on a horizontal rough plane ($$\mu$$ = 0.1 and g = 9.8 m/s²) is

A rocket of mass 100 kg burns 0.1 kg of fuel per sec. If the velocity of exhaust gas is 1 km/sec, then it lifts with an acceleration of

A bullet emerges from a barrel of length 1.2 m with a speed of 640 ms^$$-$$1. Assuming constant acceleration, the approximate time that it spends in the barrel after the gun is fired is

A body of mass 2 kg moves in a horizontal circular path of radius 5 m. At an instant, its speed is 2$$\sqrt5$$ m/s and is increasing at the rate of 3 m/s$$^2$$. The magnitude of force acting on the body at that instant is,