4th Quarter Science Grade 9

• A ball is moving horizontally so it's velocity is Constant and acceleration is (0)

  True
• A ball rolling straight down in an incline and it's velocity is Increasing and it's acceleration due to gravity is -9.8 m/s²

  True
• A chalk is thrown in an parabolic motion which followed a curved pattern. What is the chalk called?

  Projectile
• What is the overall motion called if a chall is is thrown in an parabolic pattern and followed a curved pattern?

  Projectile Motion
• What are the characteristics of a Projectile Motion?

  Acted upon by gravity

  Has 2 dimensions vertical and horizontal
• Projectiles always maintain a constant velocity.

  True
• Projectiles always experience a constant acceleration along the axis.

  True
• A sepak takraw that is kicked from a height of 2 meters follows a pattern. What is the name of the pattern?

  Parabolic
• A goalie kicked the ball at varying speed at 70°,50°,30° but they all reached the same maximum height.

  All punts have the same hang time
• What is the symbol for impulse?

  ( i )
• What is the unit for impulse?

  kg. m/s ( unit )
• What is the symbol for momentum?


  ( p )
• What is the unit for momentum?

  kg. m over s
• What is the equation for mass x velocity?

  i = F x t = ∆ p
• What is momentum?

  Known as inertia in motion
• Which has more momentum, a small car which is moving or a big bus which is not moving?

  Small car
• A moving jeep has a momentum. If it moves twice as fast, it's momentum would be?

  2x faster
• Which has greater momentum? a bowling ball having a mass of 5kg moving at 0.5 m/s or a baseball having a mass of 0.2 kg moving at 15 m/s?

  Baseball
• How can a karate chop break a board?

  When the velocity is large enough, the force that the hand/forearm is exerting on the board will be large enough to break the board
• What is the average force exerted by a passenger with a mass of 70kg on his seatbelt when his car crashes on to a concrete wall? The car moving at 17.9 m/s comes to a stop in 0.10 s.

  12530 N
• Unbalanced forces caused stationary objects to move.

  True
• For objects moving at the same velocity, a more massive object has greater inertia in motion therefore a greater momentum.

  True
• What does momentum depend in?

  Mass

  Velocity
• Momentum has vector quantity

  True
• Momentum has both magnitude and direction.

  True
• There are 2 types of momentum which are?

  Angular

  Linear
• Moving objects have velocities which can be measured directly or indirectly.


  True
• For stationary objects where the velocity is 0, momentum is also 0

  True
• When cooking heat spontaneously flows from a body of high temperature to a body of low temperature. If both keep contact long enough their temperature will become equal reaching the so called.

  Thermal Equilibrium
• ____ is used when referring to the energy it transit from hot to cold.

  Heat
• A sum of molecularkinetic energy due to random motion of molecules.

  Internal Energy
• Heat flows normally from a high temperature to a low temperature that do not require any external energy, this is called what?

  Spontaneous Process
• Requires mechanical energy to work and happens when heat flow from low temperature to high temperature.

  Non-spontaneous Process
• The ___ states that heat will never of itself flow from a cold temperature to a hot temperature object. To allow this heat must be pumped

  Second Law of Thermodynamics
• The Law of Thermodynamics is stated as:

  ∆U = Q-W
• A device that reverses the direction of heat flow

  Heat Pumps
• Projectile motion


  Objects moving in curved paths due to forces like gravity
• Projectile


  The object thrown or projected
• Trajectory


  The curved path of the projectile
• Horizontal motion


  • No acceleration due to external forces
  • Horizontal velocity remains constant throughout the motion