Part B: Fill in the blanks (1 mark each ) Fill in each blank with the correct missing information . It may be more than 1 word per blank . Place all answers on the answer key provided 18. Due to air resistance , a skydiver will reach a maximum speed called and not continue to accelerate 19. In nature , there are only fundamental forces . 20. The property of matter that resists a change in an object's motion is called 21. A stone tied to the end of a string is twirled around in a circle. If the string breaks, the stone will initially move along a tangent to the circle . This is best explained by Newton's _law. 22. According to Newton's second law , the acceleration of an object is directly proportional to the and inversely proportional to the If the gravitational force exerted by Earth on the Moon is considered the action force then , according to Newton's third law , the reaction force is the force exerted by 24. By far the weakest of the fundamental forces of nature is , Whereas the strongest 25. For a motionless elevator suspended by a cable , the two types of forces acting on the elevator are and and the magnitudes of their strengths are 26. For a car travelling with uniform motion along a horizontal stretch of highway , the forward acting force on the car provided by the compared to the frictional force provided by the road is 27. Imagine you're standing on a bathroom scale inside an elevator . The scale will read your normal weight when the elevator is or when the elevator is 28. The force that is ultimately responsible for an object's acceleration is referred to as the force 29. A 2500-kg elevator is moving vertically upward with a constant speed of 2.0 m/s. The value of the net force acting on the elevator is 30. The word which describes the motion of an object that has a net force of zero acting on it is 31. Newton's first law can really be attributed to an earlier man named 32. The gravitational field strength on the Moon is 1.6 N/kg. Your weight on the Moon (expressed as a fraction ) would be of your weight on Earth 33. The feeling of apparent weightlessness `which astronauts experience in orbit is a result of their motion which is best described 34. It is evident from experience that it is more difficult to get a heavy object sliding than it is to keep it sliding . This is because the coefficient of friction is greater than the coefficient friction 35. There are two factors which affect the amount of friction that acts on a sliding object . They are the and the