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**Chapter 4 -**Vectors Adding Vectors (Graphically & using Components) Vector Decomposition Unit Vectors Chapter 5 - Net Force & 2D Motion Projectile Motion Displacement, Velocity, & Acceleration Uniform Circular Motion Outline Chapter 6 - Identifying & Using Forces • Newton’s 2nd Law in 2D • Weight, Normal Force, Tension, Friction • Drag Force & Terminal Speed • Applying Newton’s 2nd Law**Q1**A projectile is fired straight up from a car moving with constant horizontal velocity. Where will the projectile land? • right back on the car • slightly behind the car • slightly ahead of the car • far behind the car • far ahead of the car Car**Q2**The vectors a, b, and c are related through vector addition by c = a + b. Which diagram below illustrates this relationship? • 1 • 2 • 3 • 4 • None of these b c c c b c b b a a a a 1 3 2 4**Question : True or False?**It is possible to have motion in the absence of a force • True! If a body has no acceleration, then no net force is acting on it. • True! If only a single force acts on a body, it must accelerate. • True! It is possible for a body to “round a curve” without a net force acting on it. • False! If a net force is acting on an object in the y-direction, then the object will move only in the y-direction • False!**Q3**A bomber flying in level flight must release its bomb before it is over the target. Neglecting air resistance, which one of the following is NOT true? • the bomber will be over the target when the bomb strikes • g remains constant for the bomb • the horizontal velocity of the plane equals the vertical velocity of the bomb when it hits the target • the bomb travels in a curved path • the time of flight of the bomb is independent of the horizontal speed of the plane**Q4**An object is held in place by friction on an inclined surface. The angle of inclination is increased until the object starts moving. If the surface is kept at this angle, the object • slows down. • moves at uniform speed. • speeds up. • none of the above.**Q5**Consider a horse pulling a buggy. Is the following statement true? The weight of the horse and the normal force exerted by the ground on the horse constitute an interaction pair that are always equal and opposite according to Newton’s 3rd law. • yes • no**Q6**A heavy wooden block is dragged by a force F along a rough steel plate, as shown below for two cases. The magnitude of the applied force F is the same for both cases. The normal force in (ii), as compared with the normal force in (i) is: • the same • greater • less • less for some angles of the incline and greater for others • less or greater, depending on the magnitude of the applied force F F i ii F**Q7**The vertical component of the initial velocity vector of the motion of a projectile is directly proportional to the: • angle of elevation • sine of the angle of elevation • cosine of the angle of elevation • tangent to the angle of elevation