 IB Mechanics A - Forces and Motion

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1. Which of the tables below correctly shows vector and scalar quantities?

 Scalars Vectors A. speed acceleration, displacement B. speed, displacement acceleration C. acceleration speed, displacement D. displacement speed, acceleration
2. the equation of motion v=u+at can only be applied to a body if certain conditions are met. Which of these is NOT one of these conditions?
• A. The net force is constant
• B. The acceleration is constant
• C. There is only one force acting on the body
• D. The acceleration is linear
3. When a sky diver is falling at terminal velocity
• A. The air resistance is at a minimum value
• B. There is no resultant force on the skydiver
• C. The force of gravity is at a maximum value
• D. The resultant force is still downwards
4. A school bus accelerates from 10 m/s to 20 m/s. For the first part of the journey the acceleration is constant. The bus then quickly reaches it's top speed.

Which of these graphs shows the motion up to this point? 5. Which of these acceleration - time graphs show this motion correctly? 6. This graph shows the bus approaching a traffic light. Which answer correctly states the total distance travelled and the decceleration of the bus?
• A. Distance = 40m, deceleration = 0.8 ms-2.
• B. Distance = 40m, deceleration = 1.25 ms-2.
• C. Distance = 30m, deceleration = 1.25 ms-2.
• D. Distance = 30m, deceleration = 0.8 ms-2. 7. Two of Newton's famous laws of motion are ..
• statement X: "Action and reaction are equal and opposite."
• Statement Y: " An object will continue to travel in a straight line at constant velocity unless acted on by a force."

Which of Newtons Laws are these?

• A. X is the 1st law, Y is the 2nd law.
• B. X is the 2nd law, Y is the 3rd law.
• C. X is the 3rd law, Y is the 1st law.
• D. X is the 1st law, Y is the 3rd law.

8. A remote controlled car is switched on and accelerates from rest. Which of these 4 free body diagrams correctly shows the relative sizes of the forces acting on the car? 9. Two stones are thrown from a building with identical speeds as shown. Which statements are true?

 Time to reach ground Range A. A is first to hit B lands furthest from Building B. B is first to hit B lands furthest from Building C. A is first to hit A lands furthest from Building D. B is first to hit A lands furthest from Building 10. Stone B above has a vertical and horizontal component of velocity. Which of these statements about the velocity is true?

• A. The horizontal and vertical velocities remains constant
• B. The horizontal velocity increases , the vertical velocity remains constant
• C. The vertical velocity increases , the horizontal velocity remains constant
• D. The horizontal and vertical velocities increase