12. To calculate the momentum of a pickup truck moving at 25 m/s east, it is also necessary to know which of the following?
a. Time elapsed
b. Drive force of the motor
C. Mass of the truck
d. Distance the truck travels

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

How does the kinetic energy of a charge change as the charge moves under the effect of an electric field from higher potential to lower potential? a.the kinetic energy increases.b.the kinetic energy decreases.c.the kinetic energy remains the same.d.the kinetic energy is always zero.

An object weigh 40n in air ,weigh 20n when submerged in water,and 30n when submerged in a liquid of unknown liquid density.what is the density of unknown of liquid?