Understanding Motion and Energy

Which of the following best describes Newton's First Law of Motion?

• An object will change its motion only if a force acts on it.

• Force equals mass times acceleration.

• For every action, there is an equal and opposite reaction.

• The energy of a system remains constant.

How does Newton's Second Law of Motion explain the difficulty of pushing a fully loaded shopping cart compared to an empty one?

• The mass of the cart does not affect the force needed.

• The acceleration of the cart is independent of its mass.

• More force is required to accelerate the heavier cart due to its greater mass.

• Less force is needed because the cart is already in motion.

Which scenario is an example of Newton's Third Law of Motion?

• A book resting on a table.

• A rocket launching into space.

• A car accelerating on a highway.

• A pendulum swinging back and forth.

What happens to the gravitational potential energy of a book when it is lifted to a higher shelf?

• It decreases.

• It remains constant.

• It increases.

• It becomes kinetic energy.

Which of the following is a non-contact force?

• Friction

• Tension

• Gravity

• Normal force

How does gravity affect an astronaut's weight on the moon compared to Earth?

• The astronaut weighs more on the moon.

• The astronaut weighs less on the moon.

• The astronaut's weight remains the same.

• The astronaut experiences no gravity on the moon.

In what way can friction be beneficial in everyday life?

• It causes wear and tear on machines.

• It makes it difficult to move heavy objects.

• It allows us to walk without slipping.

• It increases energy consumption in vehicles.

How does normal force change when an object is placed on an inclined plane?

• It increases with the angle of inclination.

• It decreases with the angle of inclination.

• It remains constant regardless of the angle.

• It becomes zero.

In a suspension bridge, what type of force is primarily responsible for supporting the bridge's weight?

• Frictional force

• Tension force

• Gravitational force

• Elastic force

How does air resistance affect the descent of a parachute?

• It speeds up the descent.

• It has no effect on the descent.

• It slows down the descent.

• It causes the parachute to ascend.