7th Grade Physical Science Final Exam Practice Questions

Which of the following is an example of Newton's First Law of Motion?

• An object at rest will stay at rest, and an object in motion will stay in motion with the same speed and direction, unless acted upon by an external force.

• An object in motion will eventually come to a stop on its own.

• An object at rest will immediately start moving when an external force is applied.

• An object at rest will eventually start moving on its own.

Answer explanation

The correct choice states that an object at rest stays at rest and an object in motion stays in motion unless acted upon by an external force. This directly reflects Newton's First Law of Motion, emphasizing inertia.

Newton's Second Law of Motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its:

• time

• distance

• velocity

• mass

Answer explanation

Newton's Second Law states that acceleration (a) is directly proportional to net force (F) and inversely proportional to mass (m), expressed as a = F/m. Thus, the correct answer is mass.

Tags

NGSS.MS-PS2-2

Which equation represents Newton's Second Law of Motion?

• F = md

• F = mv

• F = mv^2

• F = ma

Answer explanation

Newton's Second Law of Motion states that the force (F) acting on an object is equal to the mass (m) of the object multiplied by its acceleration (a). Therefore, the correct equation is F = ma.

Which of the following statements is true about weight?

• Weight is a measure of the force exerted on an object due to temperature.

• Weight is a measure of the force exerted on an object due to magnetism.

• Weight is a measure of the force exerted on an object due to friction.

• Weight is a measure of the force exerted on an object due to gravity.

Answer explanation

Weight is defined as the force exerted on an object due to gravity, which pulls objects toward the center of the Earth. The other statements incorrectly attribute weight to temperature, magnetism, or friction.

Tags

NGSS.MS-PS2-4

Friction is a force that opposes the motion of objects. Which of the following is an example of friction?

• When you try to push a heavy box and it doesn't move.

• When you throw a ball in the air and it falls back down.

• When lift a heavy box off the wet floor.

Answer explanation

The correct choice illustrates friction because when you try to push a heavy box and it doesn't move, the friction between the box and the surface is opposing your force, preventing motion.

Tags

NGSS.MS-PS2-2

Which type of friction occurs when an object moves through a fluid, such as air or water?

• Static friction

• Rolling friction

• Fluid friction

• Surface friction

Answer explanation

Fluid friction occurs when an object moves through a fluid, like air or water. It is the resistance encountered by the object due to the fluid's viscosity, making 'Fluid friction' the correct choice.

What is the force that keeps planets in orbit around the Sun?

• gravity

• friction

• magnetism

• centrifugal force

Answer explanation

The force that keeps planets in orbit around the Sun is gravity. It is the attractive force between the Sun and the planets, preventing them from drifting away into space.

Tags

NGSS.MS-ESS1-1

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

What is the term for the force that opposes the motion when two surfaces are in contact?

• Gravity

• Friction

• Inertia

• Momentum

Answer explanation

The force that opposes motion between two surfaces in contact is called friction. It acts to resist the sliding or rolling of one surface over another, making it the correct answer.

Which of the following is a unit of measurement for weight?

• Newton

• Joule

• Watt

• Ampere

Answer explanation

The correct choice is Newton, which is a unit of measurement for weight. Joule measures energy, Watt measures power, and Ampere measures electric current, making them unsuitable for weight measurement.

What is the effect called when an object moving in the atmosphere experiences a force opposite to its direction of motion?

• Air Resistance

• Lift

• Thrust

• Weight

Answer explanation

The effect experienced by an object moving in the atmosphere that opposes its motion is called air resistance. This force acts in the opposite direction to the object's velocity, slowing it down.