QUARTER 4

• What is kinematics the study of?

  How an object moves without forces
• What are the practical uses of kinematics?

  • Robotics
  • Setting pathways (hiking, climbing)
  • Travel time of a car
  • Sports (running, marathon)
• What is the initial speed of the car in the sample problem?

  5.00 m/s
• What is the acceleration of the car in the sample problem?

  3.00 m/s²
• How far does the car travel in 5.00 s?

  15.00 m
• What is the speed of the ball after 5.00 s if dropped from rest?

  49.05 m/s
• How long does the ball take to hit the ground when thrown downwards?

  3.57 s
• What is projectile motion?

  • Follows a curved path (trajectory)
  • Influenced by Earth's gravity
  • Vertical and horizontal directions are independent
• What is the angle of projection in the sample problem involving a rock?

  35°
• How long does the rock take to hit the ground?

  10.00 s
• What is the initial velocity of the rock in the sample problem?

  3.500 m/s
• What is the height of the cliff in the rock problem?

  125.00 m
• How long does the pen take to hit the ground from a 1.36 m tall table?

  0.52 s
• What does sports science study?

  • Enhancing the human body during intense exercise
  • Uses principles of science
• What angle is optimal for maximum javelin distance?

  ~45°
• How long does the paper airplane take to reach the girl?

  1.50 s
• What is work defined as?

  Pushing & pulling over a distance
• What is the SI unit of work?

  Joules (J)
• What are the types of work?

  1. Positive Work (+W)
  2. Negative Work (-W)
  3. Zero Work
• What is positive work?

  Force in the same direction as displacement
• What is negative work?

  Force opposite to displacement
• What is zero work?

  Force perpendicular to displacement
• What is the work done by the tractor in the sled problem?

  Work = 5,000 N * 20.00 m
• What is the total weight of the sled and load?

  14,700 N
• What is the friction force opposing the sled's motion?

  3,500 N
• What is the total work done by all forces in the sled problem?

  Work = 5,000 N - 3,500 N
• What is kinetic energy?

  Energy of an object in motion
• What does the Work-Energy Theorem state?

  Total work is the change in kinetic energy
• What happens if KEf > KEi?

  Positive work, object is going faster
• What happens if KEf < KEi?

  Negative work, object is going slower
• What is potential energy?

  Energy at rest, stored energy
• What is gravitational potential energy?

  Energy stored due to Earth's gravity
• What is the potential energy of a 2.00 kg mass at 10.0 m?

  196.2 J
• What is the relationship between gravitational potential energy and work?

  • Total work is the negative change in potential energy
  • Work done moving up is negative
  • Work done moving down is positive
• What is the relationship of KE and PE in a pendulum?

  • Max PE; 0 KE (slowing down)
  • 0 PE; Max KE (speeding up)
• What is mechanical energy?

  Relationship between potential and kinetic energy
• What is the total energy of a boulder rolling down a hill?

  Potential energy + kinetic energy
• What is the maximum height of a baseball thrown upwards?

  Height calculated from KE and PE
• What is the law of conservation of energy?

  • Energy cannot be created or destroyed
  • Can be transferred or changed into different forms
  • Total energy remains constant
• What is momentum?

  Mass in motion