Quiz 4 PHYS 104 (out of 10 marks) 1. A rocket moves through empty space in a straight line with constant speed. It is far from the gravitational inuence of any star or planet. Under these conditions, the force that must be applied to sustain its motion is. ._ a) Equal to its mass b) Equal to its weight c) Dependent on how fast it is moving d) Zero 2. Consider a rock of mass In that is thrown upwards. The magnitude of the net force acting on the rock at its maximum height 1s: a) Greater than mg b) Equal to mg c) Less than mg, but greater than zero (1) Zero 3. An object of mass 5 kg is acted upon by exactly four forces, each of magnitude 10 Newtons. Which of the following could NOT be the resulting acceleration of the object? a) 0 m/s2. b) 2 m/sz. c) 4 m/sz. d) 8 m/sz. e) 10 m/sz. 4. It is more difcult to start moving a heavy carton from rest than it is to keep pushing it with constant velocity because... a) The normal force is greater when the carton is at rest b) The force of static friction is less than the force of kinetic friction c) The force of kinetic friction is less than the force of static friction (:1) Initially, the normal force is not perpendicular to the applied force E 5. (6 marks) A 10.0 kg block is at rest on a rough horizontal surface. A force of =50.0N @ 35is applied to the block, as shown below. The coefcients of static and kinetic friction between the block and the horizontal surface are: \"5:055 and Mk=0.35. Will the block move? If not, explain Why not. If so, determine its acceleration. (Hint: compare the horizontal component of the applied force with the maximum static, friction . force to assess whether the crate accelerates; tftt does, it will be subject to kineticfrtctton)