Part -7 Motion in a plane hard Welcome to your Part -7 Motion in a plane hard A train A runs from east to west and another train B of the same mass runs from west to east at the same speed with respect to earth along the equator. Normal force by the track on train A is N1 and that on train B is N2: N1 > N2 N1 < N2 N1= N2 the information is insufficient to find the relation between N1 and N2. None Consider a case in which, the driver of a car travelling at a high speed suddenly sees a wall at a distance r directly in front of him. To avoid collision, he should apply brakes sharply he should turn the car sharply he should apply brakes and then sharply turn None of these None A particle moves with deceleration along the circle of radius R so that at any moment of time its tangential and normal accelerations are equal in magnitude. At the initial moment t = 0 the speed of the particle equals v0, then : (i) the speed of the particle as a function of the distance covered s will be v = v0 e–s/ R v = v0 es/ R v = v0 e–R/s v = v0 eR/s None A boy whirls a stone in a horizontal circle 1.8 m above the ground by means of a string with radius 1.2 m. It breaks and stone flies off horizontally, striking the ground 9.1 m (horizontal range) away. The centripetal acceleration during the circular motion was nearly: (use g = 9.8 m/s2) 94 m/s2 141 m/s2 188 m/s2 282 m/s2 None A particle of mass m begins to slide down a fixed smooth sphere from the top with negligible intial velocity. What is its tangential acceleration when it breaks off the sphere ? 2g/3 √5g/3 g g/3 None A stone of mass 1 kg tied to a light inextensible string of length L =10/3 m, whirling in a circular path in a vertical plane. The ratio of maximum tension in the string to the minimum tension in the string is 4, If g is taken to be 10 m/s2, the speed of the stone at the highest point of the circle is : 10 m/s 5√2 m/s 10√3m/s 20 m/s None A sphere of mass m is suspended by a thread of length ‘λ’ is oscillating in a vertical plane, the angular amplitude being θ0. What is the tension in the thread when it makes an angle θ with the vertical during oscillations ? If the thread can support a maximum tension of 2 mg, then what can be the maximum angular amplitude of oscillation of the sphere without breaking the rope? 3 mgcosθ – 2mg cosθ0 , θ0 = 600 3 mg cosθ + 2mg cosθ0, θ0 = 600 2mg cosθ – 3mg cosθ0 , θ0 = 300 2mg cosθ + 3mg cosθ0, θ0 = 300 None instant, then the radius of curvature of the path of the particle at that instant is directly proportional to: v3 v2 v 1/v None None None Time's up
