physics

Metals are good conductors of electricity because

• they contain free electrons
• the atoms are lightly packed 
• they have high melting point
• all of the above

Pa (Pascal) is the unit for

• Thrust
• Pressure
• Frequency
• Conductivity

Stars appears to move from east to west because

• All stars move from east to west
• The earth rotates from west to east
• The earth rotates from east to west
• The background of the stars moves from west to east

name one type of collision::

• inertia

• elastic

• plastic

what is inelastic collision?

• conserved energy

• energy is not conserved

what is the formula for momentum?

• p=vm

• p=mv

• i=mv

If we drop a steel sphere and a ping pong ball, the steel sphere will...

• hit the ground first because it has more mass
• hit the ground second because it takes longer to accelerate 
• hit the ground at the same time as the ping pong ball