SPH 3U – Review #1

MOTION (& FORCES)

  1. Compare distance, position, and displacement.
  2. How are speed and velocity different?
  3. How deep is BC’s well in metres (diagram on right)?
  4. Sketch a d : t curve, a v : t curve and an a : t curve for each of these different situations: constant velocity; constant acceleration.
  5. What is an example of uniform motion?
  6. *While prepping for the exam, Sam and Mike decide to do some practical tests. Sam leaves the start line with a speed of 0 m/s but accelerates uniformly at a rate of 2.8 m/s2 for 2.0 s then runs with a constant speed. Mike waits 1.0 s after Sam departs and begins to accelerate from rest at 3.2 m/s2 until he catches Sam.

a)How long does it take for Mike to catch Sam?

b)How far do the two lab partners travel before Mike catches Sam?

c)Sketch a d : t curve and a v : t curve for the two young physicists.

  1. What is meant by freefall? At what rate do we fall on Earth? What is terminal velocity?
  2. Why is the letter g used to symbolize the acceleration towards the centre of the Earth?
  3. If an object was dropped from 3000 m (in an airplane), what would its speed be after 4.0s? How far would the object have dropped in that time?

(MOTION &) FORCES

  1. What are the four fundamental forces? What is the unit for force and what are the base units that it is derived from?
  2. Describe Newton’s three laws of motion without formulas.
  3. What is the inverse squared law and how does it apply to gravity?
  4. Calculate ‘g’ using Newton’s 2nd law and the universal law of gravitation.
  5. What relationships do net Force, mass and acceleration have according to Newton’s 2nd Law?
  6. Why are ‘g’ and the force of gravity different when describing the properties of an object?
  7. Two objects of different mass dropped from a height in a vacuum will do what? Why?
  8. What is meant by net, resultant, or an unbalanced force? Which of Newton’s laws applies here?
  9. A 3.5 kg mass is being pulled by a 45 N force to the right along a rough floor. The mass is accelerating at 3.0 m/s2 in the same direction. What is the force of friction on the mass? What is the coefficient of friction between the floor and the mass?
  10. You are applying 8 N [E 30° S] of horizontal force on a 3 kg mass. If the net force on the mass is 2.6 N [E], calculate the missing force.
  11. Two boxes (with masses of 12 kg and 23 kg) are attached by a non-stretching rope. There is a pulling force on the first box of 38.5 N, pulling it across a frictionless floor. What tension force is there in the rope?
  12. What values are necessary to determine the force of friction between an object and a surface?
  13. Describe the occurrences of friction in a car. Which are desirable, and which are not?

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