Physics Challenge for Grade 9

What is Newton's First Law of Motion?

• An object in motion will eventually stop without any force.

• An object will change direction only if a force is applied.

• An object will accelerate if no forces are acting on it.

• An object will remain at rest or in uniform motion unless acted upon by an external force.

How does Newton's Second Law relate force, mass, and acceleration?

• Force equals mass times acceleration (F = m * a).

• Force is the product of acceleration and velocity (F = a * v).

• Acceleration is independent of mass and force.

• Force is equal to mass divided by acceleration (F = m / a).

What is the formula for calculating kinetic energy?

• KE = 0.5 * m * v

• KE = 0.5 * m * v^2

• KE = m * v

• KE = m * v^2 / 2

Define power in terms of energy and time.

• Power = Energy - Time

• Power = Time / Energy

• Power = Energy + Time

• Power = Energy / Time

What is the unit of power?

• watt

• joule

• volt

• ohm

What is the speed of sound in air at room temperature?

• 400 meters per second

• 300 meters per second

• 250 meters per second

• 343 meters per second

What is the difference between longitudinal and transverse waves?

• Longitudinal waves have no particle displacement, while transverse waves have random particle displacement.

• Longitudinal waves travel faster than transverse waves.

• Longitudinal waves have parallel particle displacement, while transverse waves have perpendicular particle displacement.

• Transverse waves can travel through solids only, while longitudinal waves can travel through liquids and gases.

What is static electricity?

• Static electricity is the flow of electric current through a conductor.

• Static electricity is the energy produced by moving water.

• Static electricity is the heat generated by friction between two surfaces.

• Static electricity is the buildup of electric charge on the surface of objects.

What is Coulomb's Law?

• Coulomb's Law: F = k * |q1 * q2| / r^2

• F = k * q1 + q2 / r

• F = k * |q1 - q2| / r^2

• F = k * q1 * q2 * r^2

How does a capacitor store electric charge?

• A capacitor stores charge by generating heat through resistance.

• A capacitor stores charge by creating a vacuum between its plates.

• A capacitor stores charge by converting it into magnetic energy.

• A capacitor stores electric charge by accumulating opposite charges on two plates separated by a dielectric.