Effects of forces on speed and direction Knowledge-Based Download PDF

Questions

1. 1.

   An object is moving due north. In which direction must a net force act to simultaneously decrease the object's speed and deflect its direction of motion toward the east?

   • A) Northeast
   • B) Northwest
   • C) Southwest
   • D) Southeast
2. 2.

   An object is initially at rest on a frictionless horizontal surface. When a constant net force begins acting on the object, how do its speed and direction of motion change?

   • A) Its speed remains zero, while its orientation continuously rotates.
   • B) Its speed increases from zero, and its direction of motion is in the direction of the net force.
   • C) Its speed increases, but its direction of motion is perpendicular to the net force.
   • D) Its speed changes to a constant non-zero value, moving in the direction opposite to the net force.
3. 3.

   An object travels along a curved path at a constant speed. What can be concluded about the net force acting on the object?

   • A) A non-zero net force acts on the object to change its direction of motion.
   • B) The net force acting on the object is zero because its speed remains constant.
   • C) A non-zero net force acts strictly in the direction of motion to maintain constant speed.
   • D) A non-zero net force acts opposite to the direction of motion to prevent it from speeding up.
4. 4.

   A hockey puck slides across frictionless ice at a steady speed in a straight line, meaning the net force acting on it is zero. How does this zero net force affect the puck's speed and direction?

   • A) Both its speed and direction remain completely unchanged.
   • B) Its speed gradually decreases to zero while its direction remains straight.
   • C) Its speed stays constant, but its direction curves unpredictably.
   • D) Its speed increases steadily because no resistive force opposes it.
5. 5.

   A toy car moves across a level floor when a constant net force is applied to it in the exact same direction as its velocity. What effect does this net force have on the car's speed and direction?

   • A) The car's speed decreases, and its direction of motion remains unchanged.
   • B) The car's speed remains constant, and its direction of motion changes.
   • C) The car's speed increases, and its direction of motion remains unchanged.
   • D) Both the car's speed and its direction of motion continuously change.
6. 6.

   A constant net force is applied to a moving object in a direction exactly opposite to its velocity. What is the immediate effect of this force on the object's motion?

   • A) The object's speed increases, and its direction of motion remains unchanged.
   • B) The object's speed decreases, and its direction of motion immediately reverses.
   • C) The object's speed decreases, and its direction of motion initially remains unchanged.
   • D) The object's speed remains constant, and its direction of motion deflects sideways.
7. 7.

   An object moves along a frictionless surface when a non-zero net force is continuously applied perpendicular to its velocity at every instant. How does this force affect the object's speed and direction of motion?

   • A) Both the speed and the direction of motion change continuously.
   • B) The speed increases continuously while the direction of motion remains unchanged.
   • C) The speed remains constant while the direction of motion changes continuously.
   • D) The speed decreases continuously while the direction of motion remains unchanged.
8. 8.

   A constant net force acts on a moving object in a direction that is neither parallel nor perpendicular to its velocity vector. How does this force affect the object's motion?

   • A) The object's speed changes, but its direction of motion remains constant.
   • B) The object's direction of motion changes, but its speed remains constant.
   • C) Neither the object's speed nor its direction of motion changes.
   • D) Both the object's speed and its direction of motion change.