Fourth Examination in Grade 9-Science

Juan and Pedro are playing billiards. They hit two balls of the same mass towards each other at the same speed. If the collision is perfectly elastic, what happens to the balls after they collide?

• Zero

• Same magnitude and direction

• Same in magnitude but opposite in direction

• Different in magnitude and opposite in direction

A motorcycle going fast midway down a hill, what is/are the energy involved?

• entirely kinetic

• entirely potential

• entirely gravitational

• both kinetic and potential

Which event is explained in the sequence of energy changes shown in the diagram below?

• a blue spotlight is on

• a runner doing stretches

• an electric fan rotates

• the battery -powered toy car runs forward

The Agus VI Hydroelectric Power Plant provides electricity to many homes in Mindanao. What energy transformation occurs in this type of power plant?

• electrical energy

• gravitational potential energy

• heat

• nuclear energy

Which event does Not describe potential energy being changed into kinetic energy?

• A cart rolling down a hill

• A rubber foam being compressed

• A student lets go a stretched slinky

• A twig falling from a branch

Which of the following shows the transformation of heat to mechanical energy?

• Archery

• Roller Coaster

• Bump Cars

• Steam Engine

Which of the following happens to raindrops?

• Loses potential energy and gains kinetic energy

• Loses both potential energy and kinetic energy

• Gains potential energy and loses kinetic energy

• Gains both potential energy and kinetic energy

A track and field athlete jumps over a hurdle. What happens to his energy at the highest point of the jump compared to when he is on the ground?

• lesser

• equal

• greater

• not related

A wind-up toy is fully wound and about to start moving. What type of energy does it have at this moment?

• kinetic but no potential energy

• potential but no kinetic energy

• both potential and kinetic energy in equal amounts

• neither potential nor kinetic energy

A science teacher asks students why energy can never be lost, only changed from one form to another. What law of physics explains this?

• Newton's Law of Motion

• Boyle's Law

• The Law of Conservation of Energy

• Archimedes' Principle