5. A merry-go-round, having a rotational mass of 220 kg.m and a radius Top View F R = 1.6 m, is pushed from rest by a person with an 85-N force F, making a 70 angle, as shown. (a) What is torque acting on the merry-go-round? (b) What is the angular acceleration of the merry-go-round? (c) Calculate 70 the angular momentum at the instant when the merry-go-round makes 24 RPM. (d) What is its kinetic energy at the same instant? 6. A negatively charged particle of -1.2 nC is placed at point O. (a) Draw the electrostatic field lines produced by this charge Q =-1.2 nc (six lines will suffice). (b) What is the electric field intensity - -... at a point 9.0 mm from O? 7. Three charged particles are fixed on a straight line 5.0 cm 10.0 cm at points O, A, and B(as shown). (a) What is the net force experienced at point A? (Hint: Use superposition O A principle of forces at A due to q1 and due to q3). If 91 = -3.6 nc 92 = +1.4 nc 93 = . particle A has a mass of 120 ug and is released, find the magnitude and direction of its acceleration