Chapter 4 - Newton's Second Law

The human body can withstand an acceleration of 10 g under certain conditions. What net force would produce this acceleration for a 50-kg person?

• 25000 N

• 2500 N

• 5000 N

• 500 N

A car has a mass of 1000 kg and accelerates at 2 m/s2. What net force is exerted on the car?

• 1500 N

• 500 N

• 2000 N

• 1000 N

A 1-kg mass at the Earth's surface weighs

• 5 N

• 1 N

• 10 N

• 12 N

A 500-N parachutist opens his chute and experiences an air resistance force of 800 N. The net force on the parachutist is then

• 500 N upward

• 300 N downward

• 300 N upward

• 500 N downward

A ball is thrown upwards and caught when it returns. Compared with its initial speed and in the presence of air resistance, the speed with which it is caught is always

• less

• more

• the same

• can't be determined

The force of friction on a sliding object is 10 N. The applied force needed to maintain a constant velocity is

• 10 N

• less than 10 N

• more than 10 N

• 0 N

A 10-kg brick and a 1-kg apple are dropped in a vacuum. The force of gravity on the brick is

• zero

• the same as the force on the apple

• one-tenth as much as the apple

• 10 times more than the apple

A rock weighs 30 N on Earth and another rock weighs 30 N on the Moon. Which rock has the greater mass?

• the one on the moon

• the one on Earth

• they have the same mass

• there is not enough information

Compared to the mass of an apple on Earth, the mass of the apple on the Moon is

• six times as much

• one sixth as much

• zero

• the same

The newton is a unit of

• mass

• force

• density

• inertia