Review: Laws of Motion

Which bodies move at a constant speed?

I. A car moving at 70 km/h in a straight path.

II. A jeepney moving on a straight road and then slowing down to stop.

III. A storm initially moving at 50 km/h northeastward and the at 60 km/h eastward.

IV. A bus moving at 40 km/h around a curve.

• III and IV only

• I and IV only

• II and III only

• I, II, and III only

Which body moves at a constant velocity?

I. A car moving at 70 km/h in a straight path.

II. A jeepney moving on a straight road and then slowing down to stop.

III. A storm initially moving at 50 km/h northeastward and the at 60 km/h eastward.

IV. A bus moving at 40 km/h around a curve.

• I

• II

• III

• IV

Which bodies are accelerating?

I. A car moving at 70 km/h in a straight path.

II. A jeepney moving on a straight road and then slowing down to stop.

III. A storm initially moving at 50 km/h northeastward and the at 60 km/h eastward.

IV. A bus moving at 40 km/h around a curve.

• I and II

• II and III

• III and IV

• II, III, and IV

TRUE or FALSE: Objects with greater mass have greater inertia; objects with less mass have less inertia.

• TRUE

• FALSE

TRUE or FALSE: Inertia is a force.

• TRUE

• FALSE

Which of the following is not a unit of force?

• $newton$

• $kg\cdot\frac{m}{s^2}$

• $kg\cdot\frac{m}{s}$

An object weighing 50 N has a mass of ___.

• 0.5 kg

• 5 kg

• 50 kg

• 5 000 kg

Which of the statement is not true to a pair of forces?

• They act in the same body.

• They occur at the same time.

• They are in opposite direction.

• They have the same magnitude.

Which situations are described by Newton's First Law?

I. Passengers in a bus are thrown forward when the bus suddenly stops; they are thrown backward when the bus suddenly starts.

II. Two boys pull a card on opposite ends and the cart moves to the right.

III. We can shake the ketchup out of a bottle by suddenly stopping the bottle when it has been set in rapid motion.

IV. In a rocket ship, as fuel burns, hot gases are kicked backward and the rocket is kicked forward.

• I and II

• I and III

• II and III

• III and IV

Which situation is described by Newton's Second Law?

I. Passengers in a bus are thrown forward when the bus suddenly stops; they are thrown backward when the bus suddenly starts.

II. Two boys pull a card on opposite ends and the cart moves to the right.

III. We can shake the ketchup out of a bottle by suddenly stopping the bottle when it has been set in rapid motion.

IV. In a rocket ship, as fuel burns, hot gases are kicked backward and the rocket is kicked forward.

• I

• II

• III

• IV