Understanding Newton's First Law

What does Newton's First Law state about objects at rest?

• They will remain at rest unless acted upon by an external force.

• They will change direction spontaneously.

• They will accelerate without any force.

• They will start moving on their own.

In the biomechanical example, what happens when the diver exerts a force on the diving board?

• The diver moves backward.

• The diver remains stationary.

• The diver is propelled into the air.

• The diving board breaks.

Why can't the diver change his trajectory while in the air?

• Because he is not moving fast enough.

• Because the air is too dense.

• Because internal forces cannot change the overall motion.

• Because he is too heavy.

What would happen to the diver if there were no air resistance and gravity?

• He would fall straight down.

• He would float in mid-air.

• He would stop moving.

• He would continue moving upwards indefinitely.

How does Newton's First Law apply to the diver's motion in the air?

• The diver can change his speed.

• The diver can change his direction.

• The diver's motion remains constant unless acted upon by an external force.

• The diver can stop in mid-air.

In space, what keeps the asteroid moving in a straight line?

• The absence of external forces.

• The asteroid's shape.

• The asteroid's speed.

• The presence of gravity.

What is the primary reason the asteroid continues in a straight line in space?

• It is made of a special material.

• It is not affected by any external forces.

• It is being pushed by a force.

• It is rotating rapidly.

What happens to the asteroid's motion when it enters Earth's atmosphere?

• It continues in a straight line.

• It stops moving.

• It accelerates upwards.

• It follows a parabolic trajectory.

Which forces act on the asteroid when it is in Earth's atmosphere?

• Only gravity.

• Only air resistance.

• No forces act on it.

• Both gravity and air resistance.

What is the effect of air resistance on the asteroid's motion in Earth's atmosphere?

• It has no effect.

• It slows down the asteroid.

• It changes the asteroid's color.

• It speeds up the asteroid.