## Question

###### 11. Which of the following is the unit vector representation ofthe vector <-3,-1,3 > ? [Hint: get the magnitude of thevector and divide each component with the magnitude]12. A pillow is thrown with an initial velocity of 8 m/s. Solvefor the total time of flight (meaning: the time it reaches themaximum height plus the time it comes back down to its originalposition)13. Vector A = 20 m, East and vector B = 30 m, East. Determinethe cross product of vector A and B.14. What must be the angle be

11. Which of the following is the unit vector representation of the vector <-3,-1,3 > ? [Hint: get the magnitude of the vector and divide each component with the magnitude] 12. A pillow is thrown with an initial velocity of 8 m/s. Solve for the total time of flight (meaning: the time it reaches the maximum height plus the time it comes back down to its original position) 13. Vector A = 20 m, East and vector B = 30 m, East. Determine the cross product of vector A and B. 14. What must be the angle between two vectors A = 2i + 2j and A = -3i - 3j? 15. An object with a velocity 10 m/s finishes one lap around a circular path at a rate of 2 m/s2 . What is the radius of the circular path? 16. If a projectile can reach a range of 8 meters in 12 seconds, how long can it reach its maximum height? Assume that the trajectory is symmetric. 17. A car accelerates from rest to 8 m/s in 20 seconds.The car continues at this constant speed for another 20 seconds. Determine the total distance travelled by the car. 18. If a 10-N force pushes a box to the right and the box is displaced 3 meters, calculate the word done by the force. 19. A 49-N rock is suspended 8 meters from the floor. What is the gravitational potential energy of the rock? 20. The net work done on an object is 50 J. If the initial kinetic energy of the object is 22 J, what is the final kinetic energy? 21. Wade pulled a 100-kg box across the floor for 20 meters. Lebron also pulled a 100-kg box across the floor for 20 meters. Wade did it in 14 seconds, Lebron finished in 4 seconds. Which of the two has greater power?