A child slides down a playground slide and feels the warmth on their hands as they touch the slide. Which type of friction is primarily involved in this situation?

• Rolling friction

• Sliding friction

• Static friction

• Fluid friction

Why do ball bearings in a wheel reduce friction?

• They change static friction to fluid friction.

• They eliminate sliding friction by allowing rolling friction.

• They increase the surface area in contact with the axle.

• They convert friction into heat energy.

Which scenario demonstrates fluid friction?

• A car braking suddenly on a dry road

• A boat moving through water

• A box pushed across the floor

• A rolling bowling ball

A heavy box stays in place even when a person pushes it. What type of friction is responsible for this?

• Sliding friction

• Rolling friction

• Static friction

• Fluid friction

Which action demonstrates reducing sliding friction?

• Applying grease to a bicycle chain

• Using sandpaper on a wooden surface

• Tightening the screws on a machine

• Adding more weight to a sled

Why do astronauts on the Moon weigh less than they do on Earth?

• The Moon has no gravity.

• The gravitational pull of the Moon is weaker than that of Earth.

• The Moon’s surface is smoother than Earth’s.

• The distance between the Moon and the Sun affects weight.

If a ball is dropped and another ball is thrown horizontally from the same height, which will hit the ground first? Ignore air resistance.

• The balls will not hit the ground

• The dropped ball will hit the ground first.
• They will hit the ground at the same time.
• The thrown ball will hit the ground first.

Which of the following scenarios demonstrates the effect of gravity?

• A kite floating in the air

• A leaf falling to the ground

• A feather suspended in water

• A helium balloon rising into the sky

Which of the following best explains why objects fall towards the Earth?

• Air pushes objects down.

• The Earth’s magnetic field attracts objects.

• The Earth’s gravity pulls objects towards its center.

• Objects naturally seek lower elevations.

If the mass of an object increases, how does gravity between it and the Earth change?

• Gravity decreases.

• Gravity remains constant.

• Gravity increases.

• Gravity is unaffected by mass.